Li SP

References (10)

Title : PP2A methylesterase PME-1 suppresses anoikis and is associated with therapy relapse of PTEN-deficient prostate cancers - Aakula_2023_Mol.Oncol_17_1007
Author(s) : Aakula A , Isomursu A , Rupp C , Erickson A , Gupta N , Kauko O , Shah P , Padzik A , Pokharel YR , Kaur A , Li SP , Trotman L , Taimen P , Rannikko A , Lammerding J , Paatero I , Mirtti T , Ivaska J , Westermarck J
Ref : Mol Oncol , 17 :1007 , 2023
Abstract : While organ-confined prostate cancer (PCa) is mostly therapeutically manageable, metastatic progression of PCa remains an unmet clinical challenge. Resistance to anoikis, a form of cell death initiated by cell detachment from the surrounding extracellular matrix, is one of the cellular processes critical for PCa progression towards aggressive disease. Therefore, further understanding of anoikis regulation in PCa might provide therapeutic opportunities. Here, we discover that PCa tumours with concomitant inhibition of two tumour suppressor phosphatases, PP2A and PTEN, are particularly aggressive, having < 50% 5-year secondary-therapy-free patient survival. Functionally, overexpression of PME-1, a methylesterase for the catalytic PP2A-C subunit, inhibits anoikis in PTEN-deficient PCa cells. In vivo, PME-1 inhibition increased apoptosis in in ovo PCa tumour xenografts, and attenuated PCa cell survival in zebrafish circulation. Molecularly, PME-1-deficient PC3 cells display increased trimethylation at lysines 9 and 27 of histone H3 (H3K9me3 and H3K27me3), a phenotype known to correlate with increased apoptosis sensitivity. In summary, our results demonstrate that PME-1 supports anoikis resistance in PTEN-deficient PCa cells. Clinically, these results identify PME-1 as a candidate biomarker for a subset of particularly aggressive PTEN-deficient PCa.
ESTHER : Aakula_2023_Mol.Oncol_17_1007
PubMedSearch : Aakula_2023_Mol.Oncol_17_1007
PubMedID: 36461911
Gene_locus related to this paper: human-PPME1

Title : Shexiang Baoxin Pill, a Traditional Chinese Herbal Formula, Rescues the Cognitive Impairments in APP\/PS1 Transgenic Mice - Hu_2020_Front.Pharmacol_11_1045
Author(s) : Hu WH , Mak SH , Zheng ZY , Xia YJ , Xu ML , Duan R , Dong TT , Li SP , Zhan CS , Shang XH , Tsim KWK
Ref : Front Pharmacol , 11 :1045 , 2020
Abstract : BACKGROUND: Shexiang Baoxin Pill (SBP), a formulated traditional Chinese medicine (TCM), has been widely used to treat cardiovascular diseases for years. This herbal mixture has been shown to promote differentiation of cultured neuronal cells. Here, we aimed to investigate the effects of SBP in attenuating cognitive impairment in APP/PS1 transgenic mice. METHODS: Ethanol and water extracts of SBP, denoted as SBP(EtOH) and SBP(water), were standardized and applied onto cultured rat pheochromocytoma PC12 cells. The potential effect of SBP(EtOH) extract in attenuating the cognitive impairments in APP/PS1 transgenic mice was shown by following lines of evidence: (i) inhibition of Abeta fibril formation, (ii) suppression of secretions of cytokines, and (iii) improvement of behavioral tests by Morris water maze. RESULTS: SBP(water) and SBP(EtOH) inhibited the formation of beta-amyloid fibrils and protected the Abeta-induced cytotoxicity in cultured PC12 cells. In APP/PS1 transgenic mice, the treatment of SBP(EtOH) inhibited expressions of NO, NOS, AChE, as well as aggregation of Abeta. Besides, the levels of pro-inflammatory cytokines were suppressed by SBP treatment in the transgenic mice. Importantly, the behavioral tests by Morris Water maze indicated that SBP attenuated cognitive impairments in APP/PS1 transgenic mice. CONCLUSION: The current result has supported the notion that SPB might ameliorate the cognitive impairment through multiple targets, suggesting that SBP could be considered as a promising anti-AD agent.
ESTHER : Hu_2020_Front.Pharmacol_11_1045
PubMedSearch : Hu_2020_Front.Pharmacol_11_1045
PubMedID: 32765267

Title : Analogous beta-Carboline Alkaloids Harmaline and Harmine Ameliorate Scopolamine-Induced Cognition Dysfunction by Attenuating Acetylcholinesterase Activity, Oxidative Stress, and Inflammation in Mice - Li_2018_Front.Pharmacol_9_346
Author(s) : Li SP , Wang YW , Qi SL , Zhang YP , Deng G , Ding WZ , Ma C , Lin QY , Guan HD , Liu W , Cheng XM , Wang CH
Ref : Front Pharmacol , 9 :346 , 2018
Abstract : The analogous beta-carboline alkaloids, harmaline (HAL) and harmine (HAR), possess a variety of biological properties, including acetylcholinesterase (AChE) inhibitory activity, antioxidant, anti-inflammatory, and many others, and have great potential for treating Alzheimer's disease (AD). However, studies have showed that the two compounds have similar structures and in vitro AChE inhibitory activities but with significant difference in bioavailability. The objective of this study was to comparatively investigate the effects of HAL and HAR in memory deficits of scopolamine-induced mice. In the present study, mice were pretreated with HAL (2, 5, and 10 mg/kg), HAR (10, 20, and 30 mg/kg) and donepezil (5 mg/kg) by intragastrically for 7 days, and were daily intraperitoneal injected with scopolamine (1 mg/kg) to induce memory deficits and then subjected to behavioral evaluation by Morris water maze. To further elucidate the underlying mechanisms of HAL and HAR in improving learning and memory, the levels of various biochemical factors and protein expressions related to cholinergic function, oxidative stress, and inflammation were examined. The results showed that HAL and HAR could effectively ameliorate memory deficits in scopolamine-induced mice. Both of them exhibited an enhancement in cholinergic function by inhibiting AChE and inducing choline acetyltransferase (ChAT) activities, and antioxidant defense via increasing the antioxidant enzymes activities of superoxide dismutase and glutathione peroxidase, and reducing maleic diadehyde production, and anti-inflammatory effects through suppressing myeloperoxidase, tumor necrosis factor alpha, and nitric oxide as well as modulation of critical neurotransmitters such as acetylcholine (ACh), choline (Ch), L-tryptophan (L-Trp), 5-hydroxytryptamine (5-HT), gamma-aminobutyric acid (gamma-GABA), and L-glutamic acid (L-Glu). Furthermore, the regulations of HAL on cholinergic function, inflammation, and neurotransmitters were more striking than those of HAR, and HAL manifested a comparable antioxidant capacity to HAR. Remarkably, the effective dosage of HAL (2 mg/kg) was far lower than that of HAR (20 mg/kg), which probably due to the evidently differences in the bioavailability and metabolic stability of the two analogs. Taken together, all these results revealed that HAL may be a promising candidate compound with better anti-amnesic effects and pharmacokinetic characteristics for the treatments of AD and related diseases.
ESTHER : Li_2018_Front.Pharmacol_9_346
PubMedSearch : Li_2018_Front.Pharmacol_9_346
PubMedID: 29755345

Title : An Essential Esterase (BroH) for the Mineralization of Bromoxynil Octanoate by a Natural Consortium of Sphingopyxis sp. Strain OB-3 and Comamonas sp. Strain 7D-2 - Chen_2013_J.Agric.Food.Chem_61_11550
Author(s) : Chen K , Liu Y , Mao DM , Liu XM , Li SP , Jiang JD
Ref : Journal of Agricultural and Food Chemistry , 61 :11550 , 2013
Abstract : A natural consortium of two bacterial strains ( Sphingopyxis sp. OB-3 and Comamonas sp. 7D-2) was capable of utilizing bromoxynil octanoate as the sole source of carbon for its growth. Strain OB-3 was able to convert bromoxynil octanoate to bromoxynil but could not use the eight-carbon side chain as its sole carbon source. Strain 7D-2 could not degrade bromoxynil octanoate, although it was able to mineralize bromoxynil. An esterase (BroH) that is involved in the conversion of bromoxynil octanoate into bromoxynil and is essential for the mineralization of bromoxynil octanoate by the consortium was isolated from strain OB-3 and molecularly characterized. BroH encodes 304 amino acids and resembles alpha/beta-hydrolase fold proteins. Recombinant BroH was overexpressed in Escherichia coli BL21 (DE3) and purified by Ni-NTA affinity chromatography. BroH was able to transform p-nitrophenyl esters (C2-C14) and showed the highest activity toward p-nitrophenyl caproate (C6) on the basis of the catalytic efficiency value (Vmax/Km). Additionally, BroH activity decreased when the aliphatic chain length increased. The optimal temperature and pH for BroH activity was found to be 35 degrees C and 7.5, respectively. On the basis of a phylogenetic analysis, BroH belongs to subfamily V of bacterial lipolytic enzymes.
ESTHER : Chen_2013_J.Agric.Food.Chem_61_11550
PubMedSearch : Chen_2013_J.Agric.Food.Chem_61_11550
PubMedID: 24224769

Title : Cloning of a novel arylamidase gene from Paracoccus sp. strain FLN-7 that hydrolyzes amide pesticides - Zhang_2012_Appl.Environ.Microbiol_78_4848
Author(s) : Zhang J , Yin JG , Hang BJ , Cai S , He J , Zhou SG , Li SP
Ref : Applied Environmental Microbiology , 78 :4848 , 2012
Abstract : The bacterial isolate Paracoccus sp. strain FLN-7 hydrolyzes amide pesticides such as diflubenzuron, propanil, chlorpropham, and dimethoate through amide bond cleavage. A gene, ampA, encoding a novel arylamidase that catalyzes the amide bond cleavage in the amide pesticides was cloned from the strain. ampA contains a 1,395-bp open reading frame that encodes a 465-amino-acid protein. AmpA was expressed in Escherichia coli BL21 and homogenously purified using Ni-nitrilotriacetic acid affinity chromatography. AmpA is a homodimer with an isoelectric point of 5.4. AmpA displays maximum enzymatic activity at 40 degrees C and a pH of between 7.5 and 8.0, and it is very stable at pHs ranging from 5.5 to 10.0 and at temperatures up to 50 degrees C. AmpA efficiently hydrolyzes a variety of secondary amine compounds such as propanil, 4-acetaminophenol, propham, chlorpropham, dimethoate, and omethoate. The most suitable substrate is propanil, with K(m) and k(cat) values of 29.5 muM and 49.2 s(-1), respectively. The benzoylurea insecticides (diflubenzuron and hexaflumuron) are also hydrolyzed but at low efficiencies. No cofactor is needed for the hydrolysis activity. AmpA shares low identities with reported arylamidases (less than 23%), forms a distinct lineage from closely related arylamidases in the phylogenetic tree, and has different biochemical characteristics and catalytic kinetics with related arylamidases. The results in the present study suggest that AmpA is a good candidate for the study of the mechanism for amide pesticide hydrolysis, genetic engineering of amide herbicide-resistant crops, and bioremediation of amide pesticide-contaminated environments.
ESTHER : Zhang_2012_Appl.Environ.Microbiol_78_4848
PubMedSearch : Zhang_2012_Appl.Environ.Microbiol_78_4848
PubMedID: 22544249

Title : SulE, a sulfonylurea herbicide de-esterification esterase from Hansschlegelia zhihuaiae S113 - Hang_2012_Appl.Environ.Microbiol_78_1962
Author(s) : Hang BJ , Hong Q , Xie XT , Huang X , Wang CH , He J , Li SP
Ref : Applied Environmental Microbiology , 78 :1962 , 2012
Abstract : De-esterification is an important degradation or detoxification mechanism of sulfonylurea herbicide in microbes and plants. However, the biochemical and molecular mechanisms of sulfonylurea herbicide de-esterification are still unknown. In this study, a novel esterase gene, sulE, responsible for sulfonylurea herbicide de-esterification, was cloned from Hansschlegelia zhihuaiae S113. The gene contained an open reading frame of 1,194 bp, and a putative signal peptide at the N terminal was identified with a predicted cleavage site between Ala37 and Glu38, resulting in a 361-residue mature protein. SulE minus the signal peptide was synthesized in Escherichia coli BL21 and purified to homogeneity. SulE catalyzed the de-esterification of a variety of sulfonylurea herbicides that gave rise to the corresponding herbicidally inactive parent acid and exhibited the highest catalytic efficiency toward thifensulfuron-methyl. SulE was a dimer without the requirement of a cofactor. The activity of the enzyme was completely inhibited by Ag(+), Cd(2+), Zn(2+), methamidophos, and sodium dodecyl sulfate. A sulE-disrupted mutant strain, DeltasulE, was constructed by insertion mutation. DeltasulE lost the de-esterification ability and was more sensitive to the herbicides than the wild type of strain S113, suggesting that sulE played a vital role in the sulfonylurea herbicide resistance of the strain. The transfer of sulE into Saccharomyces cerevisiae BY4741 conferred on it the ability to de-esterify sulfonylurea herbicides and increased its resistance to the herbicides. This study has provided an excellent candidate for the mechanistic study of sulfonylurea herbicide metabolism and detoxification through de-esterification, construction of sulfonylurea herbicide-resistant transgenic crops, and bioremediation of sulfonylurea herbicide-contaminated environments.
ESTHER : Hang_2012_Appl.Environ.Microbiol_78_1962
PubMedSearch : Hang_2012_Appl.Environ.Microbiol_78_1962
PubMedID: 22247165
Gene_locus related to this paper: 9rhiz-g9i933

Title : Degradation of cyhalofop-butyl (CyB) by Pseudomonas azotoformans strain QDZ-1 and cloning of a novel gene encoding CyB-hydrolyzing esterase - Nie_2011_J.Agric.Food.Chem_59_6040
Author(s) : Nie ZJ , Hang BJ , Cai S , Xie XT , He J , Li SP
Ref : Journal of Agricultural and Food Chemistry , 59 :6040 , 2011
Abstract : Cyhalofop-butyl (CyB) is a widely used aryloxyphenoxy propanoate (AOPP) herbicide for control of grasses in rice fields. Five CyB-degrading strains were isolated from rice field soil and identified as Agromyces sp., Stenotrophomonas sp., Aquamicrobium sp., Microbacterium sp., and Pseudomonas azotoformans; the results revealed high biodiversity of CyB-degrading bacteria in rice soil. One strain, P. azotoformans QDZ-1, degraded 84.5% of 100 mg L(-1) CyB in 5 days of incubation in a flask and utilized CyB as carbon source for growth. Strain QDZ-1 could also degrade a wide range of other AOPP herbicides. An esterase gene, chbH, which hydrolyzes CyB to cyhalofop acid (CyA), was cloned from strain QDZ-1 and functionally expressed. A chbH-disrupted mutant dchbH was constructed by insertion mutation. Mutant dchbH could not degrade and utilize CyB, suggesting that chbH was the only esterase gene responsible for CyB degradation in strain QDZ-1. ChbH hydrolyzed all AOPP herbicides tested as well as permethrin. The catalytic efficiency of ChbH toward different AOPP herbicides followed the order quizalofop-P-ethyl = fenoxaprop-P-ethyl > CyB = fluazifop-P-butyl > diclofop-methyl = haloxyfop-P-methyl; the results indicated that the chain length of the alcohol moiety strongly affected the biodegradability of the AOPP herbicides, whereas the substitutions in the aromatic ring had only a slight influence.
ESTHER : Nie_2011_J.Agric.Food.Chem_59_6040
PubMedSearch : Nie_2011_J.Agric.Food.Chem_59_6040
PubMedID: 21534595
Gene_locus related to this paper: pseaz-e9nwd3

Title : Cloning of a novel pyrethroid-hydrolyzing carboxylesterase gene from Sphingobium sp. strain JZ-1 and characterization of the gene product - Wang_2009_Appl.Environ.Microbiol_75_5496
Author(s) : Wang BZ , Guo P , Hang BJ , Li L , He J , Li SP
Ref : Applied Environmental Microbiology , 75 :5496 , 2009
Abstract : A novel esterase gene, pytH, encoding a pyrethroid-hydrolyzing carboxylesterase was cloned from Sphingobium sp. strain JZ-1. The gene contained an open reading frame of 840 bp. Sequence identity searches revealed that the deduced enzyme shared the highest similarity with many alpha/beta-hydrolase fold proteins (20 to 24% identities). PytH was expressed in Escherichia coli BL21 and purified using Ni-nitrilotriacetic acid affinity chromatography. It was a monomeric structure with a molecular mass of approximately 31 kDa and a pI of 4.85. PytH was able to transform p-nitrophenyl esters of short-chain fatty acids and a wide range of pyrethroid pesticides, and isomer selectivity was not observed. No cofactors were required for enzyme activity.
ESTHER : Wang_2009_Appl.Environ.Microbiol_75_5496
PubMedSearch : Wang_2009_Appl.Environ.Microbiol_75_5496
PubMedID: 19581484
Gene_locus related to this paper: sphwj-c0la90

Title : Isolation and Characterization of a Methomyl-Degrading Paracoccus sp. mdw-1 - Xu_2009_Pedosphere_19_238
Author(s) : Xu JL , Wu J , Wang ZC , Wang K , Li MY , Jiang JD , He J , Li SP
Ref : Pedosphere , 19 :238 , 2009
Abstract : Methomyl, an extremely toxic pesticide, is widely used in agriculture. A strain named mdw-1 capable of degrading methomyl rapidly was successfully isolated from activated sludge in this study. It could utilize methomyl as the sole carbon or nitrogen source. The optimal temperature and medium pH for its growth and methomyl biodegradation were 30 C and 7.0, respectively. It was identified as a Paracoccus sp. according to its morphological features, physiological and biochemical characteristics, and phylogenetic analysis based on the sequence of 16S rDNA. Gas chromatography-mass spectrometry (GC-MS) analysis showed that methomyl could be completely transformed to S-methyl-N-hydroxythioacetamidate in 10 h of incubation with the isolate mdw-1.
ESTHER : Xu_2009_Pedosphere_19_238
PubMedSearch : Xu_2009_Pedosphere_19_238
PubMedID:

Title : Isolation and characterization of a denitrifying monocrotophos-degrading Paracoccus sp. M-1 - Jia_2006_FEMS.Microbiol.Lett_263_155
Author(s) : Jia KZ , Cui ZL , He J , Guo P , Li SP
Ref : FEMS Microbiology Letters , 263 :155 , 2006
Abstract : A bacterium strain, which is capable of degrading monocrotophos, was isolated from sludge collected from the bottom of a wastewater treatment system of a chemical factory, and named M-1. On the basis of the results of the cellular morphology, physiological and chemotaxonomic characteristics and phylogenetic similarity of 16S rDNA gene sequences, the strain was identified as a Paracoccus sp. The ability of the strain to mineralize monocrotophos was investigated under different culture conditions. Other organophosphorus insecticides and amide herbicides were also degraded by M-1. The key enzyme (s) involved in the initial biodegradation of monocrotophos in M-1 was shown to be a constitutively expressed cytosolic protein. The addition of M-1 (10(6) CFU g(-1)) to fluvo-aquic soil and a high-sand soil containing monocrotophos (50 mg kg(-1)) resulted in a higher degradation rate than that obtained from noninoculated soil. This microbial culture has great potential utility for the bioremediation of wastewater or soil contaminated with organophosphorus pesticides and amide herbicides.
ESTHER : Jia_2006_FEMS.Microbiol.Lett_263_155
PubMedSearch : Jia_2006_FEMS.Microbiol.Lett_263_155
PubMedID: 16978350