Lee SY

References (48)

Title : Engineered polymer nanoparticles as artificial chaperones facilitating the selective refolding of denatured enzymes - Li_2024_Proc.Natl.Acad.Sci.U.S.A_121_e2403049121
Author(s) : Li Y , Yin D , Lee SY , Lv Y
Ref : Proc Natl Acad Sci U S A , 121 :e2403049121 , 2024
Abstract : Molecular chaperones assist in protein refolding by selectively binding to proteins in their nonnative states. Despite progress in creating artificial chaperones, these designs often have a limited range of substrates they can work with. In this paper, we present molecularly imprinted flexible polymer nanoparticles (nanoMIPs) designed as customizable biomimetic chaperones. We used model proteins such as cytochrome c, laccase, and lipase to screen polymeric monomers and identify the most effective formulations, offering tunable charge and hydrophobic properties. Utilizing a dispersed phase imprinting approach, we employed magnetic beads modified with destabilized whole-protein as solid-phase templates. This process involves medium exchange facilitated by magnetic pulldowns, resulting in the synthesis of nanoMIPs featuring imprinted sites that effectively mimic chaperone cavities. These nanoMIPs were able to selectively refold denatured enzymes, achieving up to 86.7% recovery of their activity, significantly outperforming control samples. Mechanistic studies confirmed that nanoMIPs preferentially bind denatured rather than native enzymes, mimicking natural chaperone interactions. Multifaceted analyses support the functionality of nanoMIPs, which emulate the protective roles of chaperones by selectively engaging with denatured proteins to inhibit aggregation and facilitate refolding. This approach shows promise for widespread use in protein recovery within biocatalysis and biomedicine.
ESTHER : Li_2024_Proc.Natl.Acad.Sci.U.S.A_121_e2403049121
PubMedSearch : Li_2024_Proc.Natl.Acad.Sci.U.S.A_121_e2403049121
PubMedID: 38691587

Title : Histochemical Identification of Motor Fascicles Using Cholinesterase Staining in Rats Using a Mixed Nerve Model - Jeong_2024_Transplant.Proc__
Author(s) : Jeong Y , Lee SY , Choi M , Eun S
Ref : Transplant Proc , : , 2024
Abstract : BACKGROUND: Inappropriate matching of motor and sensory fibers after nerve repair or grafting can lead to nerve recovery failure. Identifying the motor and sensory fascicles enables surgeons to match them accurately and correctly align nerve stumps, which is crucial for neural regeneration. Very few methods have been reported to differentiate between the sensory and motor nerve fascicles, and the replicability of these techniques remains unestablished. In this study, we aimed to assess the accuracy of axonal cholinesterase (CE) histochemical staining in distinguishing motor and sensory nerve fibers. METHODS: The femoral and sciatic nerves were harvested from rats. The specimens were immediately cut, frozen in isopentane, and cooled with liquid nitrogen. Nerve serial cross-sections were processed for hematoxylin and eosin staining, followed by CE histochemistry. The staining protocol solutions included acetylthiocholine iodide, phosphate buffer, cobalt sulfate hydrate, potassium phosphate monobasic, sulfuric acid, sodium bicarbonate, glutaraldehyde, and ammonium sulfide. RESULTS: Cross-sections of nerves containing efferent and afferent nerve fibers in segregated fascicles showed that CE activity was confined to motor neurons. A histochemical study revealed that motor fibers with high cholinesterase activity can be differentiated from sensory fibers. The motor branches of the femoral and sciatic nerves showed specific axonal staining, whereas the sensory branch did not show any specific staining. CONCLUSION: CE histochemical staining is a useful technique for distinguishing between motor and sensory nerve fibers. It can be potentially useful in improving the outcomes of nerve grafts or extremity allotransplantation surgery.
ESTHER : Jeong_2024_Transplant.Proc__
PubMedSearch : Jeong_2024_Transplant.Proc__
PubMedID: 38355371

Title : Undibacterium piscinae sp. nov., isolated from Korean shiner intestine - Lee_2019_Int.J.Syst.Evol.Microbiol_69_3148
Author(s) : Lee SY , Kang W , Kim PS , Kim HS , Sung H , Shin NR , Whon TW , Yun JH , Lee JY , Jung MJ , Jeong YS , Tak EJ , Han JE , Hyun DW , Kang MS , Lee KE , Lee BH , Bae JW
Ref : Int J Syst Evol Microbiol , 69 :3148 , 2019
Abstract : A novel Gram-stain-negative, non-spore-forming, obligate aerobic, motile, rod-shaped, and flagellated bacterium, designated S11R28(T), was isolated from the intestinal tract of a Korean shiner, Coreoleuciscus splendidus. Based on 16S rRNA gene sequences, strain S11R28(T) was identified as member of the genus Undibacterium in class Betaproteobacteria, and was closely related to Undibacterium parvum DSM 23061(T) (98.49%). The isolate grew at 4-25 degreesC, pH 6-9, with 0% (w/v) NaCl, and grew optimally at 20 degreesC, pH 8, in the absence of NaCl. The main cellular fatty acids were C(16:0) and summed features 3 (C(16:1)omega7c and/or C(16:1)omega6c). The strain possessed diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine as predominant polar lipids, and ubiquinone Q-8 as a respiratory quinone. The polyamine profile composed of 2-hydroxyputrescine, spermidine, putrescine, and benzoic acid. A genomic DNA G+C content was 51.4 mol%. The average nucleotide identity between strains S11R28(T) and U. parvum DSM 23061(T) was 78.66%. Thus, Undibacterium piscinae can be considered a novel species within the genus Undibacterium with the type strain S11R28(T) (=KCTC 62668(T)=JCM 33224(T)).
ESTHER : Lee_2019_Int.J.Syst.Evol.Microbiol_69_3148
PubMedSearch : Lee_2019_Int.J.Syst.Evol.Microbiol_69_3148
PubMedID: 31385778
Gene_locus related to this paper: 9burk-a0a6m4abh3

Title : Lespedeza bicolor Extract Improves Amyloid Beta25 - 35-Induced Memory Impairments by Upregulating BDNF and Activating Akt, ERK, and CREB Signaling in Mice - Ko_2019_Planta.Med_85_1363
Author(s) : Ko YH , Shim KY , Kim SK , Seo JY , Lee BR , Hur KH , Kim YJ , Kim SE , Do MH , Parveen A , Kim SY , Lee SY , Jang CG
Ref : Planta Med , 85 :1363 , 2019
Abstract : Lespedeza bicolor, a traditional herbal medicine widely used in Australia, North America, and Eastern Asia, has various therapeutic effects on inflammation, nephritis, hyperpigmentation, and diuresis. In this study, to evaluate the effects of L. bicolor on cognitive function, we examined whether L. bicolor improved amyloid beta-induced memory impairment and assessed the possible mechanisms in mice. Catechin, rutin, daidzein, luteolin, naringenin, and genistein were identified in the powdered extract of L. bicolor by HPCL-DAD analyses. In behavioral experiments, L. bicolor (25 and 50 mg/kg, p. o.) significantly improved amyloid beta25 - 35 (6 nmol, intracerebroventricular)-induced cognitive dysfunction in the Y-maze, novel recognition, and passive avoidance tests. Our molecular studies showed L. bicolor (25 and 50 mg/kg, p. o.) significantly recovered the reduced glutathione content as well as increased thiobarbituric acid reactive substance and acetylcholinesterase activities in the hippocampus. Furthermore, we found that L. bicolor significantly increased the expression of brain-derived neurotrophic factor, and phospho-Akt, extracellular signal-regulated kinase, and cAMP response element binding caused by amyloid beta25 - 35 in the hippocampus. In conclusion, L. bicolor exerts a potent memory-enhancing effect on cognitive dysfunction induced by amyloid beta25 - 35 in mice.
ESTHER : Ko_2019_Planta.Med_85_1363
PubMedSearch : Ko_2019_Planta.Med_85_1363
PubMedID: 31618776

Title : Microbial production of butyl butyrate, a flavor and fragrance compound - Noh_2019_Appl.Microbiol.Biotechnol_103_2079
Author(s) : Noh HJ , Lee SY , Jang YS
Ref : Applied Microbiology & Biotechnology , 103 :2079 , 2019
Abstract : Butyl butyrate (BB) has been widely used as a flavor and fragrance compound in the beverage, food, perfume, and cosmetic industries. Currently, BB is produced through two-step processes; butanol and butyrate are first produced and are used as precursors for the esterification reactions to yield BB in the next step. Recently, an alternative process to the current process has been developed by using microorganisms for the one-pot BB production. In the one-pot BB process, alcohol acyl transferases (AATs) and lipases play roles in the esterification of butanol together with their co-substrates butyryl-CoA and butyrate, respectively. In this paper, we review the characteristics of two enzymes including AAT and lipase in the esterification reaction. Also, we review the one-pot processes for BB production by employing the wild-type and engineered Clostridium species and the engineered Escherichia coli strains, with the combination of AATs and lipases.
ESTHER : Noh_2019_Appl.Microbiol.Biotechnol_103_2079
PubMedSearch : Noh_2019_Appl.Microbiol.Biotechnol_103_2079
PubMedID: 30659333

Title : Esterase-sensitive cleavable histone deacetylase inhibitor-coupled hyaluronic acid nanoparticles for boosting anticancer activities against lung adenocarcinoma - Lee_2019_Biomater.Sci_7_4624
Author(s) : Lee SY , Hong EH , Jeong JY , Cho J , Seo JH , Ko HJ , Cho HJ
Ref : Biomater Sci , 7 :4624 , 2019
Abstract : 4-Phenylbutyric acid (PBA)-installed hyaluronic acid (HA)-based nanoparticles (NPs) were developed for amplifying the anticancer potential of curcumin (CUR) for lung cancer therapy. PBA was introduced to the HA backbone as a hydrophobic segment of a nanoassembled structure and as a histone deacetylase (HDAC) inhibitor for cancer therapy. PBA was released from the HA-PBA conjugate (HAPBA) via an esterase-responsive cleavage of ester bonds in cancer cells and may affect the dissociation of NP structure. CUR-entrapped HAPBA-based NPs, with 265 nm hydrodynamic size, unimodal size distribution, negative zeta potential, and sustained drug release, were fabricated. Co-treatment of A549 cells by PBA and CUR elevated the antiproliferation efficiency compared with CUR-treatment. CUR-loaded HAPBA NPs also exhibited a significantly lower IC50 value compared with the CUR and HAPBA10 + CUR groups (p < 0.05). Cy5.5-labeled HAPBA NPs containing CUR group displayed higher accumulation in tumor tissue and less distribution in liver and spleen after intravenous injection compared with the Cy5.5-injected group in A549 tumor-bearing mouse model. Multiple dosing of CUR-loaded HAPBA NPs in A549 tumor-bearing mouse model exhibited efficient tumor growth suppression and apoptosis-inducing effects. CD44 receptor targeting and HDAC inhibiting HAPBA NPs can be used to boost the anticancer potentials of drug cargo for the therapy of CD44 receptor-expressed cancers.
ESTHER : Lee_2019_Biomater.Sci_7_4624
PubMedSearch : Lee_2019_Biomater.Sci_7_4624
PubMedID: 31451819

Title : Reply to 'Conformational fitting of a flexible oligomeric substrate does not explain the enzymatic PET degradation' -
Author(s) : Seo H , Cho IJ , Joo S , Son HF , Sagong HY , Choi SY , Lee SY , Kim KJ
Ref : Nat Commun , 10 :5582 , 2019
PubMedID: 31811201

Title : Rational Protein Engineering of Thermo-Stable PETase from Ideonella sakaiensis for Highly Efficient PET Degradation - Son_2019_ACS.Catal_9_3519
Author(s) : Son HF , Cho IJ , Joo S , Seo H , Sagong HY , Choi SY , Lee SY , Kim KJ
Ref : ACS Catal , 9 :3519 , 2019
Abstract : Widespread utilization of polyethylene terephthalate (PET) has caused a variety of environmental and health problems; thus, the enzymatic degradation of PET can be a promising solution. Although PETase from Ideonalla sakaiensis (IsPETase) has been reported to have the highest PET degradation activity under mild conditions of all PET-degrading enzymes reported to date, its low thermal stability limits its ability for efficient and practical enzymatic degradation of PET. Using the structural information on IsPETase, we developed a rational protein engineering strategy using several IsPETase variants that were screened for high thermal stability to improve PET degradation activity. In particular, the IsPETaseS121E/D186H/R280A variant, which was designed to have a stabilized beta6-beta7 connecting loop and extended subsite IIc, had a Tm value that was increased by 8.81 C and PET degradation activity was enhanced by 14-fold at 40 C in comparison with IsPETaseWT. The designed structural modifications were further verified through structure determination of the variants, and high thermal stability was further confirmed by a heat-inactivation experiment. The proposed strategy and developed variants represent an important advancement for achieving the complete biodegradation of PET under mild conditions
ESTHER : Son_2019_ACS.Catal_9_3519
PubMedSearch : Son_2019_ACS.Catal_9_3519
Gene_locus related to this paper: idesa-mheth

Title : Isoorientin improves scopolamine-induced cognitive impairments by restoring the cholinergic system, antioxidant defense, and p-CREB\/BDNF signaling in the hippocampus and frontal cortex - Ko_2019_Arch.Pharm.Res_42_722
Author(s) : Ko YH , Kwon SH , Lee SY , Jang CG
Ref : Arch Pharm Res , 42 :722 , 2019
Abstract : Isoorientin (ISO) is considered one of the most important flavonoids with various pharmacological effects such as antioxidant, anti-inflammatory, and anti-cancer activities. Despite these beneficial activities, the effects of ISO on learning and memory have not been investigated so far. The current study evaluated the memory-enhancing effects of ISO in a scopolamine-treated mouse model by using the Y-maze and passive avoidance tests. The results showed that ISO (5 and 10 mg/kg, p.o.) treatment significantly improved the cognitive impairments caused by scopolamine. Additionally, ISO significantly decreased scopolamine-induced acetylcholinesterase and thiobarbituric acid reactive substance activities in both the hippocampus and frontal cortex of mice. In addition, ISO significantly increased the levels of total superoxide dismutase induced by scopolamine in the hippocampus and frontal cortex. Moreover, Western blot results indicated that ISO reversed the decreases in expression of phosphorylated cAMP response element binding (CREB) and brain-derived neurotrophic factor (BDNF) in the hippocampus and frontal cortex of scopolamine-treated mice. Thus, our results provide initial evidence that ISO ameliorates scopolamine-induced memory and cognitive impairments partly by restoring the cholinergic system, antioxidant defense, and p-CREB/BDNF signaling pathway, thereby exhibiting memory-enhancing activities.
ESTHER : Ko_2019_Arch.Pharm.Res_42_722
PubMedSearch : Ko_2019_Arch.Pharm.Res_42_722
PubMedID: 31350730

Title : The memory-enhancing effects of 7,8,4'-trihydroxyisoflavone, a major metabolite of daidzein, are associated with activation of the cholinergic system and BDNF signaling pathway in mice - Ko_2018_Brain.Res.Bull_142_197
Author(s) : Ko YH , Kwon SH , Ma SX , Seo JY , Lee BR , Kim K , Kim SY , Lee SY , Jang CG
Ref : Brain Research Bulletin , 142 :197 , 2018
Abstract : Daidzein is one of the dietary isoflavones present in soybean-based products. After ingestion, daidzein is bioconverted into its major metabolite, 7,8,4'-trihydroxyisoflavone (THIF). Given the pharmacological importance of daidzein, 7,8,4'-THIF has also attracted the interest of researchers. However, there are no reports on the effects of 7,8,4'-THIF on cognition and memory with regard to the cholinergic system. Therefore, this study sought to evaluate the memory-enhancing effects of 7,8,4'-THIF in mice. Treatment with 7,8,4'-THIF ameliorated the cognitive impairments induced by scopolamine, a muscarinic acetylcholine receptor antagonist, in the Y-maze and passive avoidance tests. Interestingly, 7,8,4'-THIF treatment also improved cognitive function in normal mice. This treatment was also able to reverse acetylcholinesterase (AChE) and thiobarbituric acid reactive substance (TBARS) activities in the hippocampus. Finally, 7,8,4'-THIF significantly increased the expression levels of the following molecules in the hippocampus: brain-derived neurotrophic factor (BDNF); phospho extracellular signal-regulated kinase (ERK); phospho cAMP response element binding (CREB); and choline acetyltransferase (ChAT). Our data suggest that 7,8,4'-THIF, a metabolized product of daidzein, improves cognitive function by activating the cholinergic system and the BDNF/ERK/CREB signaling pathway in mice.
ESTHER : Ko_2018_Brain.Res.Bull_142_197
PubMedSearch : Ko_2018_Brain.Res.Bull_142_197
PubMedID: 30031818

Title : Novel synthetic chalcone-coumarin hybrid for Abeta aggregation reduction, antioxidation, and neuroprotection - Lee_2018_CNS.Neurosci.Ther_24_1286
Author(s) : Lee SY , Chiu YJ , Yang SM , Chen CM , Huang CC , Lee-Chen GJ , Lin W , Chang KH
Ref : CNS Neurosci Ther , 24 :1286 , 2018
Abstract : BACKGROUND: Aggregation of misfolded amyloid beta (Abeta) in senile plaques causes oxidative stress and neuronal death in Alzheimer's disease (AD). Compounds possessing antiaggregation and antioxidant properties are promising candidate compounds for AD treatment. METHODS: We examined the potential of synthetic derivatives of licochalcone A and coumarin for inhibiting Abeta aggregation, scavenging reactive oxygen species (ROS), and providing neuroprotection by using biochemical assays and Tet-On Abeta-GFP 293/SH-SY5Y cell models for AD. RESULTS: Among test compounds, LM-031, a novel chalcone-coumarin hybrid, inhibited Abeta aggregation and scavenged free oxygen radicals. LM-031 markedly reduced Abeta misfolding and ROS as well as promoted neurite outgrowth and inhibited acetylcholinesterase in Tet-On Abeta-GFP 293/SH-SY5Y cells. Mechanistic studies showed upregulation of the HSPB1 chaperone, NRF2/NQO1/GCLC pathway, and CREB/BDNF/BCL2 pathway. Decreased neurite outgrowth upon the induction of Abeta-GFP was rescued by LM-031, which was counteracted by knockdown of HSPB1, NRF2, or CREB. CONCLUSION: Taken together, these findings demonstrate that LM-031 exhibited antiaggregation, antioxidant, and neuroprotective effects against Abeta toxicity by enhancing HSPB1 and the NRF2-related antioxidant pathway as well as by activating the CREB-dependent survival and antiapoptosis pathway. These results imply that LM-031 may be a new therapeutic compound for AD.
ESTHER : Lee_2018_CNS.Neurosci.Ther_24_1286
PubMedSearch : Lee_2018_CNS.Neurosci.Ther_24_1286
PubMedID: 30596401

Title : Structural insight into molecular mechanism of poly(ethylene terephthalate) degradation - Joo_2018_Nat.Commun_9_382
Author(s) : Joo S , Cho IJ , Seo H , Son HF , Sagong HY , Shin TJ , Choi SY , Lee SY , Kim KJ
Ref : Nat Commun , 9 :382 , 2018
Abstract : Plastics, including poly(ethylene terephthalate) (PET), possess many desirable characteristics and thus are widely used in daily life. However, non-biodegradability, once thought to be an advantage offered by plastics, is causing major environmental problem. Recently, a PET-degrading bacterium, Ideonella sakaiensis, was identified and suggested for possible use in degradation and/or recycling of PET. However, the molecular mechanism of PET degradation is not known. Here we report the crystal structure of I. sakaiensis PETase (IsPETase) at 1.5 A resolution. IsPETase has a Ser-His-Asp catalytic triad at its active site and contains an optimal substrate binding site to accommodate four monohydroxyethyl terephthalate (MHET) moieties of PET. Based on structural and site-directed mutagenesis experiments, the detailed process of PET degradation into MHET, terephthalic acid, and ethylene glycol is suggested. Moreover, other PETase candidates potentially having high PET-degrading activities are suggested based on phylogenetic tree analysis of 69 PETase-like proteins.
ESTHER : Joo_2018_Nat.Commun_9_382
PubMedSearch : Joo_2018_Nat.Commun_9_382
PubMedID: 29374183
Gene_locus related to this paper: idesa-peth

Title : Metabolic engineering of Clostridium acetobutylicum for the production of butyl butyrate - Noh_2018_Appl.Microbiol.Biotechnol_102_8319
Author(s) : Noh HJ , Woo JE , Lee SY , Jang YS
Ref : Applied Microbiology & Biotechnology , 102 :8319 , 2018
Abstract : Butyl butyrate is widely used as a fragrance additive for foods and beverages. The first step in the currently used process is the production of precursors, including butanol and butyrate, from petroleum using chemical catalysts, followed by the conversion of precursors to butyl butyrate by immobilized lipase. In this work, we engineered Clostridium acetobutylicum for the selective, one-step production of butyl butyrate from glucose. C. acetobutylicum ATCC 824, possessing a strong carbon flux that yields butanol and butyryl-CoA, was selected as a host and was engineered by introducing alcohol acyltransferases (AATs) from Fragaria x ananassa (strawberry) or Malus sp. (apple). Batch culture of the engineered C. acetobutylicum strain CaSAAT expressing the strawberry SAAT gene produced 50.07smg/L of butyl butyrate with a selectivity of 84.8% of total esters produced. Also, the engineered C. acetobutylicum strain CaAAAT expressing the apple AAAT gene produced 40.60smg/L of butyl butyrate with a selectivity of 87.4%. This study demonstrated the feasibility of the one-step fermentation of butyl butyrate from glucose in the engineered C. acetobutylicum, as a proof of concept.
ESTHER : Noh_2018_Appl.Microbiol.Biotechnol_102_8319
PubMedSearch : Noh_2018_Appl.Microbiol.Biotechnol_102_8319
PubMedID: 30076425

Title : Structural Insights into Polyhydroxyalkanoates Biosynthesis - Sagong_2018_Trends.Biochem.Sci_43_790
Author(s) : Sagong HY , Son HF , Choi SY , Lee SY , Kim KJ
Ref : Trends in Biochemical Sciences , 43 :790 , 2018
Abstract : Polyhydroxyalkanoates (PHAs) are diverse biopolyesters produced by numerous microorganisms and have attracted much attention as a substitute for petroleum-based polymers. Despite several decades of study, the detailed molecular mechanisms of PHA biosynthesis have remained unknown due to the lack of structural information on the key PHA biosynthetic enzyme PHA synthase. The recently determined crystal structure of PHA synthase, together with the structures of acetyl-coenzyme A (CoA) acetyltransferase and reductase, have changed this situation. Structural and biochemical studies provided important clues for the molecular mechanisms of each enzyme as well as the overall mechanism of PHA biosynthesis from acetyl-CoA. This new information and knowledge is expected to facilitate production of designed novel PHAs and also enhanced production of PHAs.
ESTHER : Sagong_2018_Trends.Biochem.Sci_43_790
PubMedSearch : Sagong_2018_Trends.Biochem.Sci_43_790
PubMedID: 30139647

Title : 6,7,4'-Trihydroxyisoflavone, a major metabolite of daidzein, improves learning and memory via the cholinergic system and the p-CREB\/BDNF signaling pathway in mice - Ko_2018_Eur.J.Pharmacol_826_140
Author(s) : Ko YH , Kim SY , Lee SY , Jang CG
Ref : European Journal of Pharmacology , 826 :140 , 2018
Abstract : Daidzein is one of the major isoflavfones found in soy food and plants. Following ingestion, daidzein is readily converted to hydroxylated metabolites in the human body. 6,7,4'-Trihydroxyisoflavone (THIF), one of the metabolites of daidzein, has several pharmacological activities, including anti-cancer and anti-obesity properties. However, no reports exist on the effects of 6,7,4'-THIF for cognitive function in mice. The present study aimed to investigate the effects of 6,7,4'-THIF against scopolamine-induced learning and memory impairments using the Y-maze and passive avoidance test. A single administration of 6,7,4'-THIF significantly improved scopolamine-induced cognitive dysfunction in these in vivo tests. Moreover, treatment with 6,7,4'-THIF alone enhanced learning and memory performance in the same behavioral tests. Molecular studies showed that 6,7,4'-THIF significantly inhibited acetylcholinesterase and thiobarbituric acid reactive substance (TBARS) activities in the hippocampus of scopolamine-induced mice. In addition, immunohistochemistry and Western blot results revealed that 6,7,4'-THIF significantly increased brain-derived neurotrophic factor (BDNF) and phosphor cAMP response element binding (CREB) in the hippocampus of mice. Taken together, these findings suggest that 6,7,4'-THIF improves cognitive dysfunction induced by scopolamine and enhances learning and memory by activation of the cholinergic system and the p-CREB/BDNF signaling pathway in mice.
ESTHER : Ko_2018_Eur.J.Pharmacol_826_140
PubMedSearch : Ko_2018_Eur.J.Pharmacol_826_140
PubMedID: 29510125

Title : Chinese Herbal Medicine Glycyrrhiza inflataReduces Abeta Aggregation and Exerts Neuroprotection through Anti-Oxidation and Anti-Inflammation - Chiu_2018_Am.J.Chin.Med__1
Author(s) : Chiu YJ , Lee CM , Lin TH , Lin HY , Lee SY , Mesri M , Chang KH , Lin JY , Lee-Chen GJ , Chen CM
Ref : Am J Chin Med , :1 , 2018
Abstract : Amyloid [Formula: see text] (A[Formula: see text]) plays a major role in the pathogenesis of Alzheimer's disease (AD). The accumulation of misfolded A[Formula: see text] causes oxidative and inflammatory damage leading to apoptotic cell death. Chinese herbal medicine (CHM) has been widely used in clinical practice to treat neurodegenerative diseases associated with oxidative stress and neuroinflammation. This study examined the neuroprotection effects of CHM extract Glycyrrhiza inflata (G. inflata) and its active constituents, licochalcone A and liquiritigenin in AD. We examined A[Formula: see text] aggregation inhibition, anti-oxidation and neuroprotection in Tet-On A[Formula: see text]-GFP 293/SH-SY5Y cells and anti-inflammatory potential in lipopolysaccharide (LPS)-stimulated RAW 264.7 and LPS and interferon (IFN)-[Formula: see text] (LPS/IFN-[Formula: see text])-activated BV-2 cells. In addition, we applied conditioned media (CM) of BV-2 cells primed with LPS/IFN-[Formula: see text] to A[Formula: see text]-GFP SH-SY5Y cells to uncover the neuroprotective mechanisms. Our results showed that G. inflata extract and its two constituents displayed potentials of A[Formula: see text] aggregation inhibition and radical-scavenging in biochemical assays, A[Formula: see text] misfolding inhibition and reactive oxygen species (ROS) reduction in A[Formula: see text]-GFP 293 cells, as well as neurite outgrowth promotion, acetylcholinesterase inhibition and SOD2 up-regulation in A[Formula: see text]-GFP SH-SY5Y cells. Meanwhile, both G. inflata extract and its constituents suppressed NO, TNF-[Formula: see text], IL-1[Formula: see text], PGE2 and/or Iba1 productions in inflammation-stimulated RAW 264.7 or BV-2 cells. G. inflata extract and its constituents further protected A[Formula: see text]-GFP SH-SY5Y cells from BV-2 CM-induced cell death by ameliorating reduced BCL2 and attenuating increased IGFBP2, cleaved CASP3, BAD and BAX. Collectively, G. inflata extract, licochalcone A and liquiritigenin display neuroprotection through exerting anti-oxidative and anti-inflammatory activities to suppress neuronal apoptosis.
ESTHER : Chiu_2018_Am.J.Chin.Med__1
PubMedSearch : Chiu_2018_Am.J.Chin.Med__1
PubMedID: 30284464

Title : Soil metagenome-derived 3-hydroxypalmitic acid methyl ester hydrolases suppress extracellular polysaccharide production in Ralstonia solanacearum - Lee_2018_J.Biotechnol_270_30
Author(s) : Lee MH , Khan R , Tao W , Choi K , Lee SY , Lee JW , Hwang EC , Lee SW
Ref : J Biotechnol , 270 :30 , 2018
Abstract : Autoinducers are indispensable for bacterial cell-cell communication. However, due to the reliance on culture-based techniques, few autoinducer-hydrolyzing enzymes are known. In this study, we characterized soil metagenome-derived unique enzymes capable of hydrolyzing 3-hydroxypalmitic acid methyl ester (3-OH PAME), an autoinducer of the plant pathogenic bacterium Ralstonia solanacearum. Among 146 candidate lipolytic clones from a soil metagenome library, 4 unique enzymes capable of hydrolyzing the autoinducer 3-OH PAME, termed ELP86, ELP96, ELP104, and EstDL33, were selected and characterized. Phylogenetic analysis revealed that metagenomic enzymes were novel esterase/lipase candidates as they clustered as novel subfamilies of family I, V, X, and family XI. The purified enzymes displayed various levels of hydrolytic activities towards 3-OH PAME with optimum activity at 40-50 degrees C and pH 7-10. Interestingly, ELP104 also displayed N-(3-oxohexanoyl)-L-homoserine lactone hydrolysis activity. Heterologous expression of the gene encoding 3-OH PAME hydrolase in R. solanacearum significantly decreased exopolysaccharide production without affecting bacterial growth. mRNA transcription analysis revealed that genes regulated by quorum-sensing, such as phcA and xpsR, were significantly down-regulated in the stationary growth phase of R. solanacearum. Therefore, metagenomic enzymes are capable of quorum-quenching by hydrolyzing the autoinducer 3-OH PAME, which could be used as a biocontrol strategy against bacterial wilt.
ESTHER : Lee_2018_J.Biotechnol_270_30
PubMedSearch : Lee_2018_J.Biotechnol_270_30
PubMedID: 29407418
Gene_locus related to this paper: 9zzzz-a0a223he11 , 9zzzz-a0a223heg6 , 9zzzz-a0a223he13

Title : Structure and function of the N-terminal domain of Ralstonia eutropha polyhydroxyalkanoate synthase, and the proposed structure and mechanisms of the whole enzyme - Kim_2017_Biotechnol.J_12_1
Author(s) : Kim YJ , Choi SY , Kim J , Jin KS , Lee SY , Kim KJ
Ref : Biotechnol J , 12 : , 2017
Abstract : Polyhydroxyalkanoates (PHAs) are natural polyesters synthesized by numerous microorganisms as energy and reducing power storage materials, and have attracted much attention as substitutes for petroleum-based plastics. In an accompanying paper, the authors reported the crystal structure of the C-terminal domain of Ralstonia eutropha PHA synthase (PhaC1). Here, the authors report the 3D reconstructed model of full-length of R. eutropha PhaC1 (RePhaC1F ) by small angle X-ray scattering (SAXS) analysis. The catalytic C-terminal domain of RePhaC1 (RePhaC1CD ) dimer is located at the center of RePhaC1F , and the N-terminal domain of RePhaC1 (RePhaC1ND ) is located opposite the dimerization subdomain of RePhaC1CD , indicating that RePhaC1ND is not directly involved in the enzyme catalysis. The localization studies using RePhaC1F , RePhaC1ND and RePhaC1CD revealed that RePhaC1ND plays important roles in PHA polymerization by localizing the enzyme to the PHA granules and stabilizing the growing PHA polymer near the active site of RePhaC1CD . The serial truncation study on RePhaC1ND suggested that the predicted five alpha-helices (N-alpha3 to N-alpha7) are required for proper folding and granule binding function of RePhaC1ND . In addition, the authors also report the SAXS 3D reconstructed model of the RePhaC1F /RePhaMDeltaC complex (RePhaMDeltaC , PAKKA motif-truncated version of RePhaM). RePhaM forms a complex with RePhaC1 by interacting with RePhaC1ND and activates RePhaC1 by providing a more extensive surface area for interaction with the growing PHA polymer.
ESTHER : Kim_2017_Biotechnol.J_12_1
PubMedSearch : Kim_2017_Biotechnol.J_12_1
PubMedID: 27808475
Gene_locus related to this paper: alceu-phbc

Title : Crystal structure of Ralstonia eutropha polyhydroxyalkanoate synthase C-terminal domain and reaction mechanisms - Kim_2017_Biotechnol.J_12_2
Author(s) : Kim J , Kim YJ , Choi SY , Lee SY , Kim KJ
Ref : Biotechnol J , 12 : , 2017
Abstract : Polyhydroxyalkanoates (PHAs) are natural polyesters synthesized by numerous microorganisms as energy and reducing power storage materials, and have attracted much attention as substitutes for petroleum-based plastics. Here, we report the first crystal structure of Ralstonia eutropha PHA synthase at 1.8 A resolution and structure-based mechanisms for PHA polymerization. RePhaC1 contains two distinct domains, the N-terminal (RePhaC1ND ) and C-terminal domains (RePhaC1CD ), and exists as a dimer. RePhaC1CD catalyzes polymerization via non-processive ping-pong mechanism using a Cys-His-Asp catalytic triad. Molecular docking simulation of 3-hydroxybutyryl-CoA to the active site of RePhaC1CD reveals residues involved in the formation of 3-hydroxybutyryl-CoA binding pocket and substrate binding tunnel. Comparative analysis with other polymerases elucidates how different classes of PHA synthases show different substrate specificities. Furthermore, we attempted structure-based protein engineering and developed a RePhaC1 mutant with enhanced PHA synthase activity.
ESTHER : Kim_2017_Biotechnol.J_12_2
PubMedSearch : Kim_2017_Biotechnol.J_12_2
PubMedID: 27808482
Gene_locus related to this paper: alceu-phbc

Title : Liquiritigenin ameliorates memory and cognitive impairment through cholinergic and BDNF pathways in the mouse hippocampus - Ko_2017_Arch.Pharm.Res_40_1209
Author(s) : Ko YH , Kwon SH , Lee SY , Jang CG
Ref : Arch Pharm Res , 40 :1209 , 2017
Abstract : Liquiritigenin (LQ), a flavonoid extracted from the radix of Glycyrrhiza, has anti-inflammatory and neuroprotective properties. In this study, we evaluated the cognitive enhancing effects of LQ on learning and memory impairments induced by scopolamine (0.5 mg/kg, i.p.), a muscarinic antagonist, using the Y-maze, passive avoidance, and novel object recognition tests. A single administration of LQ significantly improved scopolamine-induced cognitive impairments in these behavioral tests. In addition, LQ dramatically inhibited acetylcholinesterase and thiobarbituric acid reactive substance activities in the hippocampus of scopolamine-induced mice in a dose-dependent manner. Furthermore, LQ markedly increased the protein level of brain-derived neurotrophic factor (BDNF) and phosphorylation of extracellular signal-regulated kinase (ERK) and cAMP response element binding (CREB) in the hippocampus of scopolamine-induced mice. Taken together, our results indicate that LQ may be useful for the treatment of learning and memory impairments, and that the beneficial effects of LQ are mediated, in part, by cholinergic and BDNF/ERK/CREB signaling enhancement and/or protection.
ESTHER : Ko_2017_Arch.Pharm.Res_40_1209
PubMedSearch : Ko_2017_Arch.Pharm.Res_40_1209
PubMedID: 28940173

Title : Diverse Effects of an Acetylcholinesterase Inhibitor, Donepezil, on Hippocampal Neuronal Death after Pilocarpine-Induced Seizure - Jeong_2017_Int.J.Mol.Sci_18_
Author(s) : Jeong JH , Choi BY , Kho AR , Lee SH , Hong DK , Lee SY , Song HK , Choi HC , Suh SW
Ref : Int J Mol Sci , 18 : , 2017
Abstract : Epileptic seizures are short episodes of abnormal brain electrical activity. Many survivors of severe epilepsy display delayed neuronal death and permanent cognitive impairment. Donepezil is an acetylcholinesterase inhibitor and is an effective treatment agent for Alzheimer's disease. However, the role of donepezil in seizure-induced hippocampal injury remains untested. Temporal lobe epilepsy (TLE) was induced by intraperitoneal injection of pilocarpine (25 mg/kg). Donepezil (2.5 mg/kg/day) was administered by gavage in three different settings: (1) pretreatment for three days before the seizure; (2) for one week immediately after the seizure; and (3) for three weeks from three weeks after the seizure. We found that donepezil showed mixed effects on seizure-induced brain injury, which were dependent on the treatment schedule. Pretreatment with donepezil aggravated neuronal death, oxidative injury, and microglia activation. Early treatment with donepezil for one week showed neither adverse nor beneficial effects; however, a treatment duration of three weeks starting three weeks after the seizure showed a significant reduction in neuronal death, oxidative injury, and microglia activation. In conclusion, donepezil has therapeutic effects when injected for three weeks after seizure activity subsides. Therefore, the present study suggests that the therapeutic use of donepezil for epilepsy patients requires a well-conceived strategy for administration.
ESTHER : Jeong_2017_Int.J.Mol.Sci_18_
PubMedSearch : Jeong_2017_Int.J.Mol.Sci_18_
PubMedID: 29099058

Title : Robust Type-specific Hemisynapses Induced by Artificial Dendrites - Kim_2016_Sci.Rep_6_24210
Author(s) : Kim EJ , Jeon CS , Lee SY , Hwang I , Chung TD
Ref : Sci Rep , 6 :24210 , 2016
Abstract : Type-specificity of synapses, excitatory and inhibitory, regulates information process in neural networks via chemical neurotransmitters. To lay a foundation of synapse-based neural interfaces, artificial dendrites are generated by covering abiotic substrata with ectodomains of type-specific synaptogenic proteins that are C-terminally tagged with biotinylated fluorescent proteins. The excitatory artificial synapses displaying engineered ectodomains of postsynaptic neuroligin-1 (NL1) induce the formation of excitatory presynapses with mixed culture of neurons in various developmental stages, while the inhibitory artificial dendrites displaying engineered NL2 and Slitrk3 induce inhibitory presynapses only with mature neurons. By contrast, if the artificial dendrites are applied to the axonal components of micropatterned neurons, correctly-matched synaptic specificity emerges regardless of the neuronal developmental stages. The hemisynapses retain their initially established type-specificity during neuronal development and maintain their synaptic strength provided live neurons, implying the possibility of durable synapse-based biointerfaces.
ESTHER : Kim_2016_Sci.Rep_6_24210
PubMedSearch : Kim_2016_Sci.Rep_6_24210
PubMedID: 27072994

Title : Proteogenomic characterization of antimicrobial resistance in extensively drug-resistant Acinetobacter baumannii DU202 - Lee_2014_J.Antimicrob.Chemother_69_1483
Author(s) : Lee SY , Yun SH , Lee YG , Choi CW , Leem SH , Park EC , Kim GH , Lee JC , Kim SI
Ref : J Antimicrob Chemother , 69 :1483 , 2014
Abstract : OBJECTIVES: To determine the genomic sequence of extensively drug-resistant Acinetobacter baumannii DU202 and to perform proteomic characterization of antibiotic resistance in this strain using genome data.
METHODS: The genome sequence of A. baumannii DU202 was determined using the Hi-Seq 2000 system and comparative analysis was performed to determine the unique characteristics of A. baumannii DU202. Previous proteomic results from the cell wall membrane fraction by one-dimensional electrophoresis and liquid chromatography combined with mass spectrometry analysis (1DE-LC-MS/MS), using the A. baumannii ATCC 17978 genome as a reference, were reanalysed to elucidate the resistance mechanisms of A. baumannii DU202 using strain-specific genome data. Additional proteomic data from the cytosolic fraction were also analysed.
RESULTS: The genome of A. baumannii DU202 consists of 3660 genes and is most closely related to the Korean A. baumannii 1656-2 strain. More than 144 resistance genes were annotated in the A. baumannii DU202 genome, of which 72 that encoded proteins associated with antibiotic resistance were identified in the proteomic analysis of A. baumannii DU202 cultured in tetracycline, imipenem and Luria-Bertani broth (control) medium. Strong induction of beta-lactamases, a multidrug resistance efflux pump and resistance-nodulation-cell division (RND) multidrug efflux proteins was found to be important in the antibiotic resistance responses of A. baumannii DU202.
CONCLUSIONS: Combining genomic and proteomic methods provided comprehensive information about the unique antibiotic resistance responses of A. baumannii DU202.
ESTHER : Lee_2014_J.Antimicrob.Chemother_69_1483
PubMedSearch : Lee_2014_J.Antimicrob.Chemother_69_1483
PubMedID: 24486871

Title : Metabolic engineering of Corynebacterium glutamicum for L-arginine production - Park_2014_Nat.Commun_5_4618
Author(s) : Park SH , Kim HU , Kim TY , Park JS , Kim SS , Lee SY
Ref : Nat Commun , 5 :4618 , 2014
Abstract : L-arginine is an important amino acid for diverse industrial and health product applications. Here we report the development of metabolically engineered Corynebacterium glutamicum ATCC 21831 for the production of L-arginine. Random mutagenesis is first performed to increase the tolerance of C. glutamicum to L-arginine analogues, followed by systems metabolic engineering for further strain improvement, involving removal of regulatory repressors of arginine operon, optimization of NADPH level, disruption of L-glutamate exporter to increase L-arginine precursor and flux optimization of rate-limiting L-arginine biosynthetic reactions. Fed-batch fermentation of the final strain in 5 l and large-scale 1,500 l bioreactors allows production of 92.5 and 81.2 g l(-1) of L-arginine with the yields of 0.40 and 0.35 g L-arginine per gram carbon source (glucose plus sucrose), respectively. The systems metabolic engineering strategy described here will be useful for engineering Corynebacteria strains for the industrial production of L-arginine and related products.
ESTHER : Park_2014_Nat.Commun_5_4618
PubMedSearch : Park_2014_Nat.Commun_5_4618
PubMedID: 25091334
Gene_locus related to this paper: corgl-Cgl1133 , corgl-Cgl2249 , corgl-CGL2393

Title : Draft Genome Sequence of Petroleum Oil-Degrading Marine Bacterium Pseudomonas taeanensis Strain MS-3, Isolated from a Crude Oil-Contaminated Seashore - Lee_2014_Genome.Announc_2_0
Author(s) : Lee SY , Kim SH , Lee DG , Shin S , Yun SH , Choi CW , Chung YH , Choi JS , Kahng HY , Kim SI
Ref : Genome Announc , 2 : , 2014
Abstract : Pseudomonas taeanensis MS-3(T), isolated from a crude oil-contaminated seashore in South Korea, is capable of degrading petroleum oils, such as gasoline, diesel, and kerosene. Here, we report the draft genome sequence of this strain, which consists of 5,477,045 bp, with a G+C content of 60.72%.
ESTHER : Lee_2014_Genome.Announc_2_0
PubMedSearch : Lee_2014_Genome.Announc_2_0
PubMedID: 24407626
Gene_locus related to this paper: 9psed-a0a0a1yq19 , 9psed-a0a0a1ypa2 , 9psed-a0a0a1yfb1

Title : Whole-Genome Sequence of a Novel Species, Mycobacterium yongonense DSM 45126T - Kim_2013_Genome.Announc_1_e00604
Author(s) : Kim BJ , Kim BR , Lee SY , Seok SH , Kook YH
Ref : Genome Announc , 1 : , 2013
Abstract : Here, we report the complete genome sequence of Mycobacterium yongonense DSM 45126(T), genetically closely related to the INT5 genotype of M. intracellulare.
ESTHER : Kim_2013_Genome.Announc_1_e00604
PubMedSearch : Kim_2013_Genome.Announc_1_e00604
PubMedID: 23929490
Gene_locus related to this paper: mycia-h8ivh5 , 9myco-j9waw2 , mycia-h8iug5 , 9myco-i2acb5

Title : Inhibitory Effects of Eucommia ulmoides Oliv. Bark on Scopolamine-Induced Learning and Memory Deficits in Mice - Kwon_2013_Biomol.Ther.(Seoul)_21_462
Author(s) : Kwon SH , Ma SX , Joo HJ , Lee SY , Jang CG
Ref : Biomol Ther (Seoul) , 21 :462 , 2013
Abstract : Eucommia ulmoides Oliv. Bark (EUE) is commonly used for the treatment of hypertension, rheumatoid arthritis, lumbago, and ischialgia as well as to promote longevity. In this study, we tested the effects of EUE aqueous extract in graded doses to protect and enhance cognition in scopolamine-induced learning and memory impairments in mice. EUE significantly improved the impairment of short-term or working memory induced by scopolamine in the Y-maze and significantly reversed learning and memory deficits in mice as measured by the passive avoidance and Morris water maze tests. One day after the last trial session of the Morris water maze test (probe trial session), EUE dramatically increased the latency time in the target quadrant in a dose-dependent manner. Furthermore, EUE significantly inhibited acetylcholinesterase (AChE) and thiobarbituric acid reactive substance (TBARS) activities in the hippocampus and frontal cortex in a dose-dependent manner. EUE also markedly increased brain-derived neurotrophic factor (BDNF) and phosphorylation of cAMP element binding protein (CREB) in the hippocampus of scopolamine-induced mice. Based on these findings, we suggest that EUE may be useful for the treatment of cognitive deficits, and that the beneficial effects of EUE are mediated, in part, by cholinergic signaling enhancement and/or protection.
ESTHER : Kwon_2013_Biomol.Ther.(Seoul)_21_462
PubMedSearch : Kwon_2013_Biomol.Ther.(Seoul)_21_462
PubMedID: 24404337

Title : Relaxing effect of acetylcholine on phenylephrine-induced contraction of isolated rabbit prostate strips is mediated by neuronal nitric oxide synthase - Nguyen_2013_Korean.J.Urol_54_333
Author(s) : Nguyen HB , Lee SY , Park SH , Lee MY , Chang IH , Myung SC
Ref : Korean J Urol , 54 :333 , 2013
Abstract : PURPOSE: The location of acetylcholinesterase-containing nerve fibers suggests a role for acetylcholine in both contractility and secretion in the prostate gland. The colocalization of nitrergic nerves with cholinergic nerves, and the cotransmission of nitric oxide with acetylcholine in cholinergic nerves, has been demonstrated in the prostate glands of various species. Thus, we investigated the effects of acetylcholine on phenylephrine-induced contraction and the correlation between cholinergic transmission and nitric oxide synthase by using isolated prostate strips of rabbits. MATERIALS AND
METHODS: Isolated prostate strips were contracted with phenylephrine and then treated with cumulative concentrations of acetylcholine. Changes in acetylcholine-induced relaxation after preincubation with NG-nitroarginine methyl ester, 7-nitroindazole, and aminoguanidine were measured. The effects of selective muscarinic receptor antagonists were also evaluated.
RESULTS: In the longitudinal phenylephrine-contracted strip, the cumulative application of acetylcholine (10(-9) to 10(-4) M) elicited a concentration-dependent relaxation effect. Acetylcholine-induced relaxation was inhibited not only by nitric oxide synthase inhibitors (10 microM L-NAME or 10 microM 7-nitroindazole) but also by 10 microM atropine and some selective muscarinic receptor antagonists (10(-6) M 11-([2-[(diethylamino)methyl]-1-piperdinyl]acetyl)-5,11-dihydro-6H-pyrido[2,3-b][ 1,4]benzodiazepine-6-one and 10(-6) M 4-diphenylacetoxy-N-methyl-piperidine). In contrast, relaxation was significantly increased by pretreatment of the strips with 10 mM L-arginine.
CONCLUSIONS: Acetylcholine relaxed phenylephrine-induced contractions of isolated rabbit prostate strips. This relaxation may be mediated via both cholinergic and constitutive nitric oxide synthase with both the M2 and M3 receptors possibly playing key roles.
ESTHER : Nguyen_2013_Korean.J.Urol_54_333
PubMedSearch : Nguyen_2013_Korean.J.Urol_54_333
PubMedID: 23700500

Title : Draft genome sequence of the biocontrol bacterium Bacillus amyloliquefaciens strain M27 - Lee_2012_J.Bacteriol_194_6934
Author(s) : Lee SY , Kim BY , Ahn JH , Song J , Seol YJ , Kim WG , Weon HY
Ref : Journal of Bacteriology , 194 :6934 , 2012
Abstract : Bacillus amyloliquefaciens strain M27 is a biocontrol agent with antagonistic activities against a wide range of fungal pathogens. Here we present the 3.86-Mb draft genome sequence of the bacterium with the aims of providing insights into the genomic basis of its antifungal mechanism and facilitating its application in the biocontrol of plant diseases.
ESTHER : Lee_2012_J.Bacteriol_194_6934
PubMedSearch : Lee_2012_J.Bacteriol_194_6934
PubMedID: 23209201
Gene_locus related to this paper: baca2-a7z924

Title : Chronic Treatment with Squid Phosphatidylserine Activates Glucose Uptake and Ameliorates TMT-Induced Cognitive Deficit in Rats via Activation of Cholinergic Systems - Park_2012_Evid.Based.Complement.Alternat.Med_2012_601018
Author(s) : Park HJ , Lee SY , Shim HS , Kim JS , Kim KS , Shim I
Ref : Evid Based Complement Alternat Med , 2012 :601018 , 2012
Abstract : The present study examined the effects of squid phosphatidylserine (Squid-PS) on the learning and memory function and the neural activity in rats with TMT-induced memory deficits. The rats were administered saline or squid derived Squid-PS (Squid-PS 50 mg kg(-1), p.o.) daily for 21 days. The cognitive improving efficacy of Squid-PS on the amnesic rats, which was induced by TMT, was investigated by assessing the passive avoidance task and by performing choline acetyltransferase (ChAT) and acetylcholinesterase (AchE) immunohistochemistry. 18F-Fluorodeoxyglucose and performed a positron emission tomography (PET) scan was also performed. In the passive avoidance test, the control group which were injected with TMT showed a markedly lower latency time than the non-treated normal group (P < 0.05). However, treatment of Squid-PS significantly recovered the impairment of memory compared to the control group (P < 0.05). Consistent with the behavioral data, Squid-PS significantly alleviated the loss of ChAT immunoreactive neurons in the hippocampal CA3 compared to that of the control group (P < 0.01). Also, Squid-PS significantly increased the AchE positive neurons in the hippocampal CA1 and CA3. In the PET analysis, Squid-PS treatment increased the glucose uptake more than twofold in the frontal lobe and the hippocampus (P < 0.05, resp.). These results suggest that Squid-PS may be useful for improving the cognitive function via regulation of cholinergic enzyme activity and neural activity.
ESTHER : Park_2012_Evid.Based.Complement.Alternat.Med_2012_601018
PubMedSearch : Park_2012_Evid.Based.Complement.Alternat.Med_2012_601018
PubMedID: 22675385

Title : Neuroprotective effects of Eucommia ulmoides Oliv. Bark on amyloid beta(25-35)-induced learning and memory impairments in mice - Kwon_2011_Neurosci.Lett_487_123
Author(s) : Kwon SH , Lee HK , Kim JA , Hong SI , Kim SY , Jo TH , Park YI , Lee CK , Kim YB , Lee SY , Jang CG
Ref : Neuroscience Letters , 487 :123 , 2011
Abstract : In the present study, we examined whether aqueous extract of Eucommia ulmoides Oliv. Bark (EUE) with graded doses exerted its neuroprotective effects on amyloid beta(25-35) (Abeta(25-35))-induced learning and memory impairments in mice. Mice received a single intracerebroventricular (i.c.v.) injection of Abeta(25-35) 6 nmol as the critical factor in Alzheimer's disease (AD), cognition was evaluated using Y-maze, passive avoidance, and Morris water maze tests. EUE significantly improved the Abeta(25-35)-induced memory deficit in the Y-maze test. Also, EUE increased step-through latency time with Abeta(25-35)-induced learning and memory deficits in the passive avoidance test. In addition, EUE decreased the escape latencies with Abeta(25-35)-induced cognitive impairments in the Morris water maze test. In the probe trial session, EUE increased time spent in the target quadrant. In the in vitro study, EUE was found to inhibit acetylcholinesterase (AChE) activity in a dose-dependent manner (IC50 value; 172 mug/ml). Ex vivo study, EUE significantly inhibited AChE activity in the hippocampus and frontal cortex. These results demonstrate that EUE possesses potent neuroprotective effects and that its beneficial effects are mediated, in part, by AChE inhibition, and therefore, might be a potential candidate in neurodegenerative diseases such as AD.
ESTHER : Kwon_2011_Neurosci.Lett_487_123
PubMedSearch : Kwon_2011_Neurosci.Lett_487_123
PubMedID: 20974223

Title : Complete genome sequence of the metabolically versatile plant growth-promoting endophyte Variovorax paradoxus S110 - Han_2011_J.Bacteriol_193_1183
Author(s) : Han JI , Choi HK , Lee SW , Orwin PM , Kim J , Laroe SL , Kim TG , O'Neil J , Leadbetter JR , Lee SY , Hur CG , Spain JC , Ovchinnikova G , Goodwin L , Han C
Ref : Journal of Bacteriology , 193 :1183 , 2011
Abstract : Variovorax paradoxus is a microorganism of special interest due to its diverse metabolic capabilities, including the biodegradation of both biogenic compounds and anthropogenic contaminants. V. paradoxus also engages in mutually beneficial interactions with both bacteria and plants. The complete genome sequence of V. paradoxus S110 is composed of 6,754,997 bp with 6,279 predicted protein-coding sequences within two circular chromosomes. Genomic analysis has revealed multiple metabolic features for autotrophic and heterotrophic lifestyles. These metabolic diversities enable independent survival, as well as a symbiotic lifestyle. Consequently, S110 appears to have evolved into a superbly adaptable microorganism that is able to survive in ever-changing environmental conditions. Based on our findings, we suggest V. paradoxus S110 as a potential candidate for agrobiotechnological applications, such as biofertilizer and biopesticide. Because it has many associations with other biota, it is also suited to serve as an additional model system for studies of microbe-plant and microbe-microbe interactions.
ESTHER : Han_2011_J.Bacteriol_193_1183
PubMedSearch : Han_2011_J.Bacteriol_193_1183
PubMedID: 21183664
Gene_locus related to this paper: varps-c5cla8 , varps-c5cld3 , varps-c5cle8 , varps-c5cmg7 , varps-c5cmn3 , varps-c5cmq5 , varps-c5cn77 , varps-c5cpt8 , varps-c5cqf4 , varps-c5crj1 , varps-c5crm2 , varps-c5csa3 , varps-c5csp0 , varps-c5ct29 , varps-c5ct59 , varps-c5ctz6 , varps-c5cu01 , varps-c5cu02 , varps-c5cuk9 , varps-c5cw29 , varps-c5czm3 , varps-c5czm7 , varps-c5czs2 , varps-c5czw9 , varps-c5czx0 , varps-c5czz1 , varps-c5d0w2 , varps-c5d1f5 , varps-c5d1m4 , varps-c5d1p7 , varps-c5d1r3 , varps-c5d033 , varpd-t1x730 , varps-c5cyt5 , varps-rutd

Title : Tailor-made type II Pseudomonas PHA synthases and their use for the biosynthesis of polylactic acid and its copolymer in recombinant Escherichia coli - Yang_2011_Appl.Microbiol.Biotechnol_90_603
Author(s) : Yang TH , Jung YK , Kang HO , Kim TW , Park SJ , Lee SY
Ref : Applied Microbiology & Biotechnology , 90 :603 , 2011
Abstract : Previously, we have developed metabolically engineered Escherichia coli strains capable of producing polylactic acid (PLA) and poly(3-hydroxybutyrate-co-lactate) [P(3HB-co-LA)] by employing evolved Clostridium propionicum propionate CoA transferase (Pct(Cp)) and Pseudomonas sp. MBEL 6-19 polyhydroxyalkanoate (PHA) synthase 1 (PhaC1(Ps6-19)). Introduction of mutations four sites (E130, S325, S477, and Q481) of PhaC1( Ps6-19) have been found to affect the polymer content, lactate mole fraction, and molecular weight of P(3HB-co-LA). In this study, we have further engineered type II Pseudomonas PHA synthases 1 (PhaC1s) from Pseudomonas chlororaphis, Pseudomonas sp. 61-3, Pseudomonas putida KT2440, Pseudomonas resinovorans, and Pseudomonas aeruginosa PAO1 to accept short-chain-length hydroxyacyl-CoAs including lactyl-CoA and 3-hydroxybutyryl-CoA as substrates by site-directed mutagenesis of four sites (E130, S325, S477, and Q481). All PhaC1s having mutations in these four sites were able to accept lactyl-CoA as a substrate and supported the synthesis of P(3HB-co-LA) in recombinant E. coli, whereas the wild-type PhaC1s could not accumulate polymers in detectable levels. The contents, lactate mole fractions, and the molecular weights of P(3HB-co-LA) synthesized by recombinant E. coli varied depending upon the source of the PHA synthase and the mutants used. PLA homopolymer could also be produced at ca. 7 wt.% by employing the several PhaC1 variants containing E130D/S325T/S477G/Q481K quadruple mutations in wild-type E. coli XL1-Blue.
ESTHER : Yang_2011_Appl.Microbiol.Biotechnol_90_603
PubMedSearch : Yang_2011_Appl.Microbiol.Biotechnol_90_603
PubMedID: 21221571
Gene_locus related to this paper: psech-PHAC1

Title : The genome sequence of E. coli W (ATCC 9637): comparative genome analysis and an improved genome-scale reconstruction of E. coli - Archer_2011_BMC.Genomics_12_9
Author(s) : Archer CT , Kim JF , Jeong H , Park JH , Vickers CE , Lee SY , Nielsen LK
Ref : BMC Genomics , 12 :9 , 2011
Abstract : BACKGROUND: Escherichia coli is a model prokaryote, an important pathogen, and a key organism for industrial biotechnology. E. coli W (ATCC 9637), one of four strains designated as safe for laboratory purposes, has not been sequenced. E. coli W is a fast-growing strain and is the only safe strain that can utilize sucrose as a carbon source. Lifecycle analysis has demonstrated that sucrose from sugarcane is a preferred carbon source for industrial bioprocesses.
RESULTS: We have sequenced and annotated the genome of E. coli W. The chromosome is 4,900,968 bp and encodes 4,764 ORFs. Two plasmids, pRK1 (102,536 bp) and pRK2 (5,360 bp), are also present. W has unique features relative to other sequenced laboratory strains (K-12, B and Crooks): it has a larger genome and belongs to phylogroup B1 rather than A. W also grows on a much broader range of carbon sources than does K-12. A genome-scale reconstruction was developed and validated in order to interrogate metabolic properties.
CONCLUSIONS: The genome of W is more similar to commensal and pathogenic B1 strains than phylogroup A strains, and therefore has greater utility for comparative analyses with these strains. W should therefore be the strain of choice, or 'type strain' for group B1 comparative analyses. The genome annotation and tools created here are expected to allow further utilization and development of E. coli W as an industrial organism for sucrose-based bioprocesses. Refinements in our E. coli metabolic reconstruction allow it to more accurately define E. coli metabolism relative to previous models.
ESTHER : Archer_2011_BMC.Genomics_12_9
PubMedSearch : Archer_2011_BMC.Genomics_12_9
PubMedID: 21208457
Gene_locus related to this paper: ecoli-entf , ecoli-fes , ecoli-yafa , ecoli-yeiG , ecoli-yhet , ecoli-yiel

Title : Neuroprotective effects of chlorogenic acid on scopolamine-induced amnesia via anti-acetylcholinesterase and anti-oxidative activities in mice - Kwon_2010_Eur.J.Pharmacol_649_210
Author(s) : Kwon SH , Lee HK , Kim JA , Hong SI , Kim HC , Jo TH , Park YI , Lee CK , Kim YB , Lee SY , Jang CG
Ref : European Journal of Pharmacology , 649 :210 , 2010
Abstract : Chlorogenic acid is a major polyphenolic component of many plants and beverages, and is particularly abundant in coffee. We evaluated the neuroprotective effects of chlorogenic acid on learning and memory impairment induced by scopolamine (0.5 mg/kg, i.p.), a muscarinic antagonist, using the Y-maze, passive avoidance, and Morris water maze tests. The chlorogenic acid significantly improved the impairment of short-term or working memory induced by scopolamine in the Y-maze test, and significantly reversed cognitive impairments in mice as measured by the passive avoidance test. In addition, chlorogenic acid decreased escape latencies in the Morris water maze test. In a probe trial session, chlorogenic acid increased the latency time in the target quadrant in a dose-dependent manner. Ex vivo, chlorogenic acid inhibited acetylcholinesterase activity in the hippocampus and frontal cortex. Chlorogenic acid also decreased malondialdehyde levels in the hippocampus and frontal cortex. In vitro, chlorogenic acid was found to inhibit acetylcholinesterase activity (IC(5)(0)=98.17 mug/ml) and free radical scavenging activity (IC(5)(0)=3.09 mug/ml) in a dose-dependent manner. These results indicate that chlorogenic acid may exert anti-amnesic activity via inhibition of acetylcholinesterase and malondialdehyde in the hippocampus and frontal cortex.
ESTHER : Kwon_2010_Eur.J.Pharmacol_649_210
PubMedSearch : Kwon_2010_Eur.J.Pharmacol_649_210
PubMedID: 20854806

Title : Enhanced display of lipase on the Escherichia coli cell surface, based on transcriptome analysis - Baek_2010_Appl.Environ.Microbiol_76_971
Author(s) : Baek JH , Han MJ , Lee SH , Lee SY
Ref : Applied Environmental Microbiology , 76 :971 , 2010
Abstract : A cell surface display system was developed using Escherichia coli OmpC as an anchoring motif. The fused Pseudomonas fluorescens SIK W1 lipase was successfully displayed on the surface of E. coli cells, and the lipase activity could be enhanced by the coexpression of the gadBC genes identified by transcriptome analysis.
ESTHER : Baek_2010_Appl.Environ.Microbiol_76_971
PubMedSearch : Baek_2010_Appl.Environ.Microbiol_76_971
PubMedID: 19948866

Title : Loganin improves learning and memory impairments induced by scopolamine in mice - Kwon_2009_Eur.J.Pharmacol_619_44
Author(s) : Kwon SH , Kim HC , Lee SY , Jang CG
Ref : European Journal of Pharmacology , 619 :44 , 2009
Abstract : Loganin is an iridoid glycoside found in the Flos lonicerae, Fruit cornus, and Strychonos nux vomica. We investigated the effect of loganin on learning and memory impairments induced by scopolamine (0.5mg/kg, i.p.), a muscarinic antagonist, using the Y-maze, passive avoidance, and the Morris water maze tests in mice. In the Y-maze test, loganin (40 mg/kg, p.o.) significantly improved the scopolamine-induced memory impairment. In addition, loganin (20 and 40 mg/kg, p.o.) significantly reversed scopolamine-induced impairments measured by the passive avoidance and the Morris water maze tests. A day after the last trial session of the Morris water maze test (probe trial session), loganin (20 and 40 mg/kg) dose-dependently increased the latency time in the target quadrant. Furthermore, loganin significantly inhibited acetylcholinesterase activity in the hippocampus and frontal cortex. Loganin may have anti-amnesic activity that may hold significant therapeutic value in alleviating certain memory impairments observed in Alzheimer's disease.
ESTHER : Kwon_2009_Eur.J.Pharmacol_619_44
PubMedSearch : Kwon_2009_Eur.J.Pharmacol_619_44
PubMedID: 19666019

Title : Is subnanomolar binding affinity required for the in vivo imaging of acetylcholinesterase? Studies on 18F-labeled G379 - Lee_2006_Nucl.Med.Biol_33_91
Author(s) : Lee SY , Choe YS , Ryu EK , Iimura Y , Choi Y , Lee KH , Kim BT
Ref : Nucl Med Biol , 33 :91 , 2006
Abstract : Acetylcholinesterase (AChE) is an important cholinergic marker of Alzheimer's disease (AD) and shows reduced activity in postmortem AD brain tissues. 1-(4-Fluorobenzyl)-4-[(5,6-dimethoxy-1-oxoindan-2-fluoro-2-yl)methyl]piperidine (G379, ), an AChE inhibitor with a subnanomolar IC(50) (0.56 nM), was prepared as a (18)F-labeled radioligand ([(18)F]) and evaluated in mice. Metabolism studies of [(18)F] showed no metabolites in the mouse brain. Tissue distribution studies demonstrated its uniform regional distribution in the mouse brain, suggesting that this radioligand is not suitable for the in vivo imaging of AChE. This result along with reports on radiolabeled N-benzylpiperidine lactam benzisoxazole (IC(50) < 1 nM) and other radiolabeled benzylpiperidine derivatives (IC(50) > 1 nM) suggested that a subnanomolar IC(50) may not be the only important factor in determining the suitability of a radioligand for in vivo studies of AChE.
ESTHER : Lee_2006_Nucl.Med.Biol_33_91
PubMedSearch : Lee_2006_Nucl.Med.Biol_33_91
PubMedID: 16459263

Title : Display of lipase on the cell surface of Escherichia coli using OprF as an anchor and its application to enantioselective resolution in organic solvent - Lee_2005_Biotechnol.Bioeng_90_223
Author(s) : Lee SH , Choi JI , Han MJ , Choi JH , Lee SY
Ref : Biotechnol Bioeng , 90 :223 , 2005
Abstract : We have developed a new cell surface display system using a major outer membrane protein of Pseudomonas aeruginosa OprF as an anchoring motif. Pseudomonas fluorescens SIK W1 lipase gene was fused to the truncated oprF gene by C-terminal deletion fusion strategy. The truncated OprF-lipase fusion protein was successfully displayed on the surface of Escherichia coli. Localization of the truncated OprF-lipase fusion protein was confirmed by western blot analysis, immunofluorescence microscopy, and whole-cell lipase activity. To examine the enzymatic characteristics of the cell surface displayed lipase, the whole-cell enzyme activity and stability were determined under various conditions. Cell surface displayed lipase showed the highest activity at 37 degrees C and pH 8.0. It retained over 80% of initial activity after incubation for a week in both aqueous solution and organic solvent. When the E. coli cells displaying lipases were used for enantioselective resolution of racemic 1-phenylethanol in hexane, (R)-phenyl ethyl acetate was successfully obtained with the enantiomeric excess of greater than 96% in 36 h of reaction. These results suggest that E. coli cells displaying lipases using OprF as an anchoring motif can be employed for various biotechnological applications both in aqueous and nonaqueous phases.
ESTHER : Lee_2005_Biotechnol.Bioeng_90_223
PubMedSearch : Lee_2005_Biotechnol.Bioeng_90_223
PubMedID: 15739170

Title : The genome sequence of the ethanologenic bacterium Zymomonas mobilis ZM4 - Seo_2005_Nat.Biotechnol_23_63
Author(s) : Seo JS , Chong H , Park HS , Yoon KO , Jung C , Kim JJ , Hong JH , Kim H , Kim JH , Kil JI , Park CJ , Oh HM , Lee JS , Jin SJ , Um HW , Lee HJ , Oh SJ , Kim JY , Kang HL , Lee SY , Lee KJ , Kang HS
Ref : Nat Biotechnol , 23 :63 , 2005
Abstract : We report the complete genome sequence of Zymomonas mobilis ZM4 (ATCC31821), an ethanologenic microorganism of interest for the production of fuel ethanol. The genome consists of 2,056,416 base pairs forming a circular chromosome with 1,998 open reading frames (ORFs) and three ribosomal RNA transcription units. The genome lacks recognizable genes for 6-phosphofructokinase, an essential enzyme in the Embden-Meyerhof-Parnas pathway, and for two enzymes in the tricarboxylic acid cycle, the 2-oxoglutarate dehydrogenase complex and malate dehydrogenase, so glucose can be metabolized only by the Entner-Doudoroff pathway. Whole genome microarrays were used for genomic comparisons with the Z. mobilis type strain ZM1 (ATCC10988) revealing that 54 ORFs predicted to encode for transport and secretory proteins, transcriptional regulators and oxidoreductase in the ZM4 strain were absent from ZM1. Most of these ORFs were also found to be actively transcribed in association with ethanol production by ZM4.
ESTHER : Seo_2005_Nat.Biotechnol_23_63
PubMedSearch : Seo_2005_Nat.Biotechnol_23_63
PubMedID: 15592456
Gene_locus related to this paper: zymmo-DLH , zymmo-GAA , zymmo-metx , zymmo-q5nkz4 , zymmo-q5nmh0 , zymmo-q5nmm8 , zymmo-q5nmn0 , zymmo-q5nmz5 , zymmo-q5nnu4 , zymmo-q5npe2 , zymmo-q5nph2 , zymmo-q5npn6 , zymmo-q5nq91 , zymmo-q5nrh7 , zymmo-q5nnr5

Title : Synthesis and evaluation of 5,7-dihydro-3-[2-[1-(4-[18F]-fluorobenzyl)-4-piperidinyl]ethyl]-6H-pyrrolo[3,2-f] -1,2-benzisoxazol-6-one for in vivo mapping of acetylcholinesterase - Lee_2004_Nucl.Med.Commun_25_591
Author(s) : Lee SY , Choe YS , Kim YR , Paik JY , Choi BW , Kim SE , Lee KH , Choi Y , Kim BT
Ref : Nucl Med Commun , 25 :591 , 2004
Abstract : OBJECTIVES: Acetylcholinesterase (AChE) is an important cholinergic marker for the diagnosis of Alzheimer's disease (AD). A recent study has demonstrated that C-labelled 5,7-dihydro-7-methyl-3-[2-[1-(phenylmethyl)-4-piperidinyl]ethyl]-6H-pyrrolo[3,2-f ]-1,2-benzisoxazol-6-one (CP-126,998) shows promising results. The demethylated form of this ligand (CP-118,954) is a more potent and selective inhibitor than CP-126,998. In this study, therefore, CP-118,954 was labelled with F and evaluated for the in vivo mapping of AChE.
METHODS: The 4-fluoro (1). and 2-fluoro (2). derivatives of CP-118,954 were synthesized from 4-methyl-3-nitroanisole in 11 steps. Their in vitro binding affinities to AChE were measured using Ellman's method. The preparation of [F]-1 was carried out by reductive alkylation of the piperidine precursor with 4-[F]-fluorobenzaldehyde, followed by high-performance liquid chromatography (HPLC) purification. In vitro autoradiography was performed by incubating rat brain coronal slices with [F]-1. Tissue distribution studies were performed in mouse brain and the data were expressed as the percentage of the injected dose per gram of tissue (%ID x g).
RESULTS: Two fluorine-substituted AChE inhibitors were synthesized and their in vitro binding data showed that the 4-fluoro and 2-fluoro derivatives (1 and 2) had similar or superior binding affinity to that of the unsubstituted ligand, CP-118,954. The F-labelled ligand was synthesized in 20-35% radiochemical yield (EOS) and with high effective specific activity (36-42 GBq x micromol). Autoradiography showed high uptake of [F]-1 in the striatum and this striatal uptake was completely inhibited by the unlabelled ligand 1. Tissue distribution studies demonstrated that high radioactivity was accumulated in the striatum, an AChE-rich region.
CONCLUSIONS: This study demonstrates that [F]-1 may hold promise as a radioligand for the in vivo mapping of AChE.
ESTHER : Lee_2004_Nucl.Med.Commun_25_591
PubMedSearch : Lee_2004_Nucl.Med.Commun_25_591
PubMedID: 15167519

Title : The genome sequence of the capnophilic rumen bacterium Mannheimia succiniciproducens - Hong_2004_Nat.Biotechnol_22_1275
Author(s) : Hong SH , Kim JS , Lee SY , In YH , Choi SS , Rih JK , Kim CH , Jeong H , Hur CG , Kim JJ
Ref : Nat Biotechnol , 22 :1275 , 2004
Abstract : The rumen represents the first section of a ruminant animal's stomach, where feed is collected and mixed with microorganisms for initial digestion. The major gas produced in the rumen is CO(2) (65.5 mol%), yet the metabolic characteristics of capnophilic (CO(2)-loving) microorganisms are not well understood. Here we report the 2,314,078 base pair genome sequence of Mannheimia succiniciproducens MBEL55E, a recently isolated capnophilic Gram-negative bacterium from bovine rumen, and analyze its genome contents and metabolic characteristics. The metabolism of M. succiniciproducens was found to be well adapted to the oxygen-free rumen by using fumarate as a major electron acceptor. Genome-scale metabolic flux analysis indicated that CO(2) is important for the carboxylation of phosphoenolpyruvate to oxaloacetate, which is converted to succinic acid by the reductive tricarboxylic acid cycle and menaquinone systems. This characteristic metabolism allows highly efficient production of succinic acid, an important four-carbon industrial chemical.
ESTHER : Hong_2004_Nat.Biotechnol_22_1275
PubMedSearch : Hong_2004_Nat.Biotechnol_22_1275
PubMedID: 15378067
Gene_locus related to this paper: mansm-metx , mansm-q65px2 , mansm-q65qb2 , mansm-q65qj2 , mansm-q65qj7 , mansm-q65qj9 , mansm-q65qm9 , mansm-q65qn0 , mansm-q65rl0 , mansm-q65sn4 , mansm-q65sq6 , mansm-q65sr6 , mansm-q65u71 , mansm-q65u91 , mansm-q65uj5 , mansm-q65wp9

Title : Organizational and mutational analysis of a complete FR-008\/candicidin gene cluster encoding a structurally related polyene complex - Chen_2003_Chem.Biol_10_1065
Author(s) : Chen S , Huang X , Zhou X , Bai L , He J , Jeong KJ , Lee SY , Deng Z
Ref : Chemical Biology , 10 :1065 , 2003
Abstract : The complete gene cluster for biosynthesis of a polyene complex, FR-008, spans 137.2 kb of the genome of Streptomyces sp. FR-008 consisting of six genes for a modular PKS and 15 additional genes. The extensive similarity to the partially characterized candicidin gene cluster in Streptomyces griseus IMRU3570, especially for genes involved in mycosamine biosynthesis, prompted us to compare the compounds produced by Streptomyces sp. FR-008 and Streptomyces griseus IMRU3570, and we found that FR-008 and candicidin complex are identical. A model for biosynthesis of a set of four structurally related FR-008/candicidin compounds was proposed. Deletion of the putative regulatory genes abolished antibiotic production, while disruption of putative glycosyltransferase and GDP-ketosugar aminotransferase functionalities led to the productions of a set of nonmycosaminated aglycones and a novel polyene complex with attachment of altered sugar moiety, respectively.
ESTHER : Chen_2003_Chem.Biol_10_1065
PubMedSearch : Chen_2003_Chem.Biol_10_1065
PubMedID: 14652074
Gene_locus related to this paper: 9acto-q6w5p8 , strgr-pabt

Title : Comparative Toxicities of Pyriproxyfen and Thiamethoxam against the Sweetpotato Whitefly, Bemisia tabaci (Homoptera: Aleyrodidae) - Lee_2002_J.Asia.Pac.Entomol_5_117
Author(s) : Lee YS , Lee SY , Park EC , Kim JH , Kim GH
Ref : Journal of Asia-Pacific Entomology , 5 :117 , 2002
Abstract : This study was conducted to determine the comparative toxicities of pyriproxyfen and thiamethoxam on the sweetpotato whitefly, Bemisia tabaci biotype B. Ovicidal effect of pyriproxyfen (100 ppm) showed 94.5%, which was = 8 higher times than that of thiamethoxam (50 ppm) at the recommended concentration. The nymphal mortalities of both insecticides treated on the 3rd instar stage were over 85%. Thiamethoxam was very effective against adults, but the activity of pyriproxyfen was relatively low. Longevity and fecundity of newly emerged adults from the treated pupae of two chemicals were adveresely affected. Unlike pyriproxyfen, thiamethoxam highly showed root up-take systemic effect on nymphs and adults of B. tabaci. Pyriproxyfen and thiamethoxam showed residual effects against B. tabaci and particularly, thiamethoxam maintained high control effect with over 90% up to 7 days after treatment. In the control efficacy test on B. tabaci, the control values of pyriproxyfen and thiamethoxam at 9 days after treatment were 92.0 and 99.3%, respectively.
ESTHER : Lee_2002_J.Asia.Pac.Entomol_5_117
PubMedSearch : Lee_2002_J.Asia.Pac.Entomol_5_117

Title : A simple and efficient in vitro method for metabolism studies of radiotracers - Lee_2001_Nucl.Med.Biol_28_391
Author(s) : Lee SY , Choe YS , Kim DH , Park BN , Kim SE , Choi Y , Lee KH , Lee J , Kim BT
Ref : Nucl Med Biol , 28 :391 , 2001
Abstract : In vitro metabolism of acetylcholinesterase inhibitors containing 3-[(18)F]fluoromethylbenzyl- ([(18)F]1) and 4-[(18)F]fluorobenzyl-piperidine moieties ([(18)F]2) was studied and compared with the in vivo metabolism. Defluorination of the [(18)F]1 mainly occurred to generate [(18)F]fluoride ion both in vitro and in vivo. In contrast, the [(18)F]2 was converted into an unknown polar metabolite in both metabolism methods and another metabolite, 4-[(18)F]fluorobenzoic acid in vitro. These results demonstrated that the in vitro method can be used to predict the in vivo metabolism of both radiotracers.
ESTHER : Lee_2001_Nucl.Med.Biol_28_391
PubMedSearch : Lee_2001_Nucl.Med.Biol_28_391
PubMedID: 11395311

Title : The opdB locus encodes the trypsin-like peptidase activity of Treponema denticola - Fenno_2001_Infect.Immun_69_6193
Author(s) : Fenno JC , Lee SY , Bayer CH , Ning Y
Ref : Infect Immun , 69 :6193 , 2001
Abstract : High levels of Treponema denticola in subgingival dental plaque are associated with severe periodontal disease. T. denticola, along with Porphyromonas gingivalis and Bacteroides forsythus, are the only cultivatable oral microorganisms that produce significant amounts of "trypsin-like" peptidase activity. The ability of subgingival plaque to hydrolyze N-alpha-benzoyl-DL-arginine-2-naphthylamide (BANA) is associated with high levels of one or more of these organisms. The purpose of this study was to identify the gene encoding trypsin-like activity in T. denticola and thus facilitate molecular-level studies of its potential role in disease. Using published peptide sequences of a T. denticola surface-associated oligopeptidase with BANA-hydrolyzing activity, we identified the gene, designated opdB, in an apparently noncoding region of the T. denticola genome unannotated contigs (11/2000; http:\/\/www.tigr.org). The opdB gene begins with a TTG start codon and encodes a 685-residue peptide with high homology to the oligopeptidase B family in prokaryotes and eukaryotes. An isogenic T. denticola opdB mutant was constructed by allelic replacement mutagenesis using an ermF/AM gene cassette. The mutant lacked BANA-hydrolyzing activity and had a slightly slower growth rate than the parent strain. This mutant will be used in future studies of interactions of T. denticola with host cells and tissue.
ESTHER : Fenno_2001_Infect.Immun_69_6193
PubMedSearch : Fenno_2001_Infect.Immun_69_6193
PubMedID: 11553560
Gene_locus related to this paper: trede-Q93EK3

Title : Synthesis and biological evaluation of 1-(4-[18F]fluorobenzyl)-4-[(5,6-dimethoxy-1-oxoindan-2-yl)methyl]piperidine for in vivo studies of acetylcholinesterase - Lee_2000_Nucl.Med.Biol_27_741
Author(s) : Lee SY , Choe YS , Sugimoto H , Kim SE , Hwang SH , Lee K , Choi Y , Lee J , Kim B
Ref : Nucl Med Biol , 27 :741 , 2000
Abstract : We synthesized and evaluated 1-(4-fluorobenzyl)-4-[(5,6-dimethoxy-1-oxoindan-2-yl)methyl]piperidine (4-FDP), which is an analog of donepezil. The 4-[(18)F]FDP was prepared by reductive alkylation of debenzylated donepezil with 4-[(18)F]fluorobenzaldehyde in high radiochemical yield (decay-corrected, 40-52%) and with high effective specific activity (30-38 GBq/micromol). Tissue distribution studies in mice demonstrated nonspecific distribution of the 4-[(18)F]FDP in brain regions, suggesting that this radioligand may not be a suitable agent for in vivo studies of acetylcholinesterase (AChE), despite its potent in vitro biological activity.
ESTHER : Lee_2000_Nucl.Med.Biol_27_741
PubMedSearch : Lee_2000_Nucl.Med.Biol_27_741
PubMedID: 11150705

Title : Cloning of the Alcaligenes latus polyhydroxyalkanoate biosynthesis genes and use of these genes for enhanced production of Poly(3-hydroxybutyrate) in Escherichia coli - Choi_1998_Appl.Environ.Microbiol_64_4897
Author(s) : Choi JI , Lee SY , Han K
Ref : Applied Environmental Microbiology , 64 :4897 , 1998
Abstract : Polyhydroxyalkanoates (PHAs) are microbial polyesters that can be used as completely biodegradable polymers, but the high production cost prevents their use in a wide range of applications. Recombinant Escherichia coli strains harboring the Ralstonia eutropha PHA biosynthesis genes have been reported to have several advantages as PHA producers compared with wild-type PHA-producing bacteria. However, the PHA productivity (amount of PHA produced per unit volume per unit time) obtained with these recombinant E. coli strains has been lower than that obtained with the wild-type bacterium Alcaligenes latus. To endow the potentially superior PHA biosynthetic machinery to E. coli, we cloned the PHA biosynthesis genes from A. latus. The three PHA biosynthesis genes formed an operon with the order PHA synthase, beta-ketothiolase, and reductase genes and were constitutively expressed from the natural promoter in E. coli. Recombinant E. coli strains harboring the A. latus PHA biosynthesis genes accumulated poly(3-hydroxybutyrate) (PHB), a model PHA product, more efficiently than those harboring the R. eutropha genes. With a pH-stat fed-batch culture of recombinant E. coli harboring a stable plasmid containing the A. latus PHA biosynthesis genes, final cell and PHB concentrations of 194.1 and 141.6 g/liter, respectively, were obtained, resulting in a high productivity of 4.63 g of PHB/liter/h. This improvement should allow recombinant E. coli to be used for the production of PHB with a high level of economic competitiveness.
ESTHER : Choi_1998_Appl.Environ.Microbiol_64_4897
PubMedSearch : Choi_1998_Appl.Environ.Microbiol_64_4897
PubMedID: 9835580
Gene_locus related to this paper: alcla-PHBC