Cui H

References (28)

Title : Corner Engineering: Tailoring Enzymes for Enhanced Resistance and Thermostability in Deep Eutectic Solvents - Wang_2023_Angew.Chem.Int.Ed.Engl__e202315125
Author(s) : Wang X , Sheng Y , Cui H , Qiao J , Song Y , Li X , Huang H
Ref : Angew Chem Int Ed Engl , :e202315125 , 2023
Abstract : Deep eutectic solvents (DESs), heralded for their synthesis simplicity, economic viability, and reduced volatility and flammability, have found increasing application in biocatalysis. However, challenges persist due to a frequent diminution in enzyme activity and stability. Herein, we developed a general protein engineering strategy, termed corner engineering, to acquire DES-resistant and thermostable enzymes via precisely tailoring of the transition region in enzyme structure. Employing Bacillus subtilis lipase A (BSLA) as a model, we delineated the engineering process, yielding five multi-DESs resistant variants with highly improved thermostability, such as K889E/N89K exhibited up to a 10.0-fold catalytic efficiency (kcat/KM) increase in 30% (v/v) ChCl:acetamide and 4.1-fold in 95% (v/v) ChCl:ethylene glycol accompanying 6.7-fold thermal resistance improvement than wild type at ~50 degreesC. The generality of the optimized approach was validated by two extra industrial enzymes, endo-beta-1,4-glucanase PvCel5A (used for biofuel production) and esterase Bs2Est (plastics degradation). The molecular investigations revealed that increased water molecules at substrate binding sites and finetuned helix formation at the corner region are two dominant determinants governing elevated resistance and thermostability. This study, coupling corner engineering with obtained molecular insights, illuminates enzyme-DES interaction patterns and fosters the rational design of more DES-resistant and thermostable enzymes in biocatalysis and biotransformation.
ESTHER : Wang_2023_Angew.Chem.Int.Ed.Engl__e202315125
PubMedSearch : Wang_2023_Angew.Chem.Int.Ed.Engl__e202315125
PubMedID: 38010210
Gene_locus related to this paper: bacsu-lip , bacsu-pnbae

Title : Structural insights into catalytical capability for CPT11 hydrolysis and substrate specificity of a novel marine microbial carboxylesterase, E93 - Li_2023_Front.Microbiol_13_1081094
Author(s) : Li Y , Rong Z , Li Z , Cui H , Li J , Xu XW
Ref : Front Microbiol , 13 :1081094 , 2023
Abstract : Introduction: CPT11 (Irinotecan; 7-ethyl-10-[4-(1-piperidino)-1-piperidino] carbonyloxycamptothecin) is an important camptothecin-based broad-spectrum anticancer prodrug. The activation of its warhead, SN38 (7-ethyl-10-hydroxycamptothecin), requires hydrolysis by carboxylesterases. NPC (7-ethyl-10-[4-(1-piperidino)-1-amino] carbonyloxycamptothecin) is a metabolic derivative of CPT11 and is difficult to be hydrolyzed by human carboxylesterase. Microbial carboxylesterase with capability on both CPT11 and NPC hydrolysis is rarely reported. A marine microbial carboxylesterase, E93, was identified to hydrolyze both substrates in this study. This enzyme was an appropriate subject for uncovering the catalytic mechanism of carboxylesterases to CPT11 and NPC hydrolysis. Methods: X-ray diffraction method was applied to obtain high-resolution structure of E93. Molecular docking was adopted to analyze the interaction of E93 with p -NP ( p -nitrophenyl), CPT11, and NPC substrates. Mutagenesis and enzymatic assay were adopted to verify the binding pattern of substrates. Results: Three core regions (Region A, B, and C) of the catalytic pocket were identified and their functions on substrates specificity were validated via mutagenesis assays. The Region A was involved in the binding with the alcohol group of all tested substrates. The size and hydrophobicity of the region determined the binding affinity. The Region B accommodated the acyl group of p -NP and CPT11 substrates. The polarity of this region determined the catalytic preference to both substrates. The Region C specifically accommodated the acyl group of NPC. The interaction from the acidic residue, E428, contributed to the binding of E93 with NPC. Discussion: The study analyzed both unique and conserved structures of the pocket in E93, for the first time demonstrating the discrepancy of substrate-enzyme interaction between CPT11 and NPC. It also expanded the knowledge about the substrate specificity and potential application of microbial Family VII carboxylesterases.
ESTHER : Li_2023_Front.Microbiol_13_1081094
PubMedSearch : Li_2023_Front.Microbiol_13_1081094
PubMedID: 36756200
Gene_locus related to this paper: 9sphn-E93

Title : A novel near-infrared fluorescent probe for high-sensitivity detection of butyrylcholinesterase in various pathological states - Jiang_2023_Spectrochim.Acta.A.Mol.Biomol.Spectrosc_308_123801
Author(s) : Jiang Y , Cui H , Yu Q
Ref : Spectrochim Acta A Mol Biomol Spectrosc , 308 :123801 , 2023
Abstract : Butyrylcholinesterase (BChE) is a crucial hydrolytic enzyme predominantly synthesized in the liver, playing a significant role in conditions like liver disorders, diabetes, Alzheimer's disease, and fat metabolism regulation. This study aims to address the current limitations in visualizing BChE activity in diseases at various states by introducing an ultra-sensitive near-infrared fluorescent probe, FDCM-BChE. The probe was engineered to have several properties, such as a large Stokes shift, rapid response time, high stability, excellent selectivity, and low detection limits. We validated the efficacy of FDCM-BChE in quantifying BChE activity in human serum and leveraged its low cytotoxicity for cellular imaging. The study revealed the downregulation of BChE activity in liver cancer and hepatic injury and the upregulation in diabetes. Thus, FDCM-BChE shows promise as a tool for specific applications, providing insights into diseases associated with BChE activity.
ESTHER : Jiang_2023_Spectrochim.Acta.A.Mol.Biomol.Spectrosc_308_123801
PubMedSearch : Jiang_2023_Spectrochim.Acta.A.Mol.Biomol.Spectrosc_308_123801
PubMedID: 38142494

Title : Discovery and mechanism-guided engineering of BHET hydrolases for improved PET recycling and upcycling - Li_2023_Nat.Commun_14_4169
Author(s) : Li A , Sheng Y , Cui H , Wang M , Wu L , Song Y , Yang R , Li X , Huang H
Ref : Nat Commun , 14 :4169 , 2023
Abstract : Although considerable research achievements have been made to address the plastic crisis using enzymes, their applications are limited due to incomplete degradation and low efficiency. Herein, we report the identification and subsequent engineering of BHETases, which have the potential to improve the efficiency of PET recycling and upcycling. Two BHETases (ChryBHETase and BsEst) are identified from the environment via enzyme mining. Subsequently, mechanism-guided barrier engineering is employed to yield two robust and thermostable deltaBHETases with up to 3.5-fold enhanced k(cat)/K(M) than wild-type, followed by atomic resolution understanding. Coupling deltaBHETase into a two-enzyme system overcomes the challenge of heterogeneous product formation and results in up to 7.0-fold improved TPA production than seven state-of-the-art PET hydrolases, under the conditions used here. Finally, we employ a deltaBHETase-joined tandem chemical-enzymatic approach to valorize 21 commercial post-consumed plastics into virgin PET and an example chemical (p-phthaloyl chloride) for achieving the closed-loop PET recycling and open-loop PET upcycling.
ESTHER : Li_2023_Nat.Commun_14_4169
PubMedSearch : Li_2023_Nat.Commun_14_4169
PubMedID: 37443360
Gene_locus related to this paper: 9flao-ChryBHETase , bacsu-pnbae

Title : Using a Battery of Bioassays to Assess the Toxicity of Wastewater Treatment Plant Effluents in Industrial Parks - Yang_2023_Toxics_11_702
Author(s) : Yang B , Cui H , Gao J , Cao J , Klobucar G , Li M
Ref : Toxics , 11 :702 , 2023
Abstract : Bioassays, as an addition to physico-chemical water quality evaluation, can provide information on the toxic effects of pollutants present in the water. In this study, a broad evaluation of environmental health risks from industrial wastewater along the Yangtze River, China, was conducted using a battery of bioassays. Toxicity tests showed that the wastewater treatment processes were effective at lowering acetylcholinesterase (AChE) inhibition, HepG2 cells' cytotoxicity, the estrogenic effect in T47D-Kbluc cells, DNA damage of Euglena gracilis and the mutagenicity of Salmonella typhimurium in the analyzed wastewater samples. Polycyclic aromatic hydrocarbons (PAHs) were identified as potential major toxic chemicals of concern in the wastewater samples of W, J and T wastewater treatment plants; thus, the potential harm of PAHs to aquatic organisms has been investigated. Based on the health risk assessment model, the risk index of wastewater from the industrial parks along the Yangtze River was below one, indicating that the PAHs were less harmful to human health through skin contact or respiratory exposure. Overall, the biological toxicity tests used in this study provide a good basis for the health risk assessment of industrial wastewater and a scientific reference for the optimization and operation of the treatment process.
ESTHER : Yang_2023_Toxics_11_702
PubMedSearch : Yang_2023_Toxics_11_702
PubMedID: 37624206

Title : Bisphenol AF induces multiple behavioral and biochemical changes in zebrafish (Danio rerio) at different life stages - Rao_2022_Aquat.Toxicol_253_106345
Author(s) : Rao C , Cao X , Li L , Zhou J , Sun D , Li B , Guo S , Yuan R , Cui H , Chen J
Ref : Aquat Toxicol , 253 :106345 , 2022
Abstract : As common environmental endocrine-disrupting chemicals (EDCs), bisphenol AF (BPAF) raises potential concerns for aquatic organisms due to its widespread presence and continued release in the aquatic environment. This research aimed to use zebrafish embryos and adult fish to explore the effects of environmentally relevant concentrations (5 g/L), 50 g/L and 500 g/L of BPAF on zebrafish embryonic development, behavioral alterations, and the potential mechanisms driving these effects. The results showed that 500 g/L of BPAF severely affected the growth and development of embryos. In behavioral experiments, all concentrations of BPAF significantly inhibited the locomotor activity of larvae, 50 and 500 g/L BPAF significantly altered the anxiety-like and aggressive behavior of adult zebrafish. Furthermore, environmentally relevant concentrations and higher concentrations of BPAF induced varying degrees of oxidative stress in both embryonic and adult fish. The most significant histopathological changes and decreased acetylcholinesterase (AChE) activity were observed in the brain at 50 and 500 g/L of BPAF. We hypothesized that oxidative stress is an important cause of behavioral disturbances in larvae and adult fish. To our best knowledge, the present experiment is a pioneer in studying the effects of BPAF on a variety of complex behaviors (swimming performance, anxiety-like, social behavior, aggression) in zebrafish, which emphasizes the potential health risk of higher concentrations of BPAF in terms of induced neurotoxicity.
ESTHER : Rao_2022_Aquat.Toxicol_253_106345
PubMedSearch : Rao_2022_Aquat.Toxicol_253_106345
PubMedID: 36351319

Title : Bladder epithelial cell phosphate transporter inhibition protects mice against uropathogenic Escherichia coli infection - Pang_2022_Cell.Rep_39_110698
Author(s) : Pang Y , Cheng Z , Zhang S , Li S , Li X , Zhang X , Feng Y , Cui H , Chen Z , Liu L , Li Q , Huang J , Zhang M , Zhu S , Wang L , Feng L
Ref : Cell Rep , 39 :110698 , 2022
Abstract : Urinary tract infections are predominantly caused by uropathogenic Escherichia coli (UPEC). UPEC infects bladder epithelial cells (BECs) via fusiform vesicles, escapes into the cytosol to evade exocytosis, and establishes intracellular bacterial communities (IBCs) for the next round of infection. The UPEC vesicle escape mechanism remains unclear. Here we show that UPEC senses host immune responses and initiates escape by upregulating a key phospholipase. The UPEC phospholipase PldA disrupts the vesicle membrane, and pldA expression is activated by phosphate reduction in vesicles. The host phosphate transporter PIT1 is located on the fusiform vesicle membrane, transporting phosphate into the cytosol. UPEC infection upregulates PIT1 via nuclear factor kappaB (NF-kappaB), resulting in phosphate reduction. Silencing PIT1 blocks UPEC vesicle escape in BECs, inhibits IBC formation in mouse bladders, and protects mice from UPEC infection. Our results shed light on pathogenic bacteria responding to intracellular phosphate shortage and tackling host defense and provide insights for development of new therapeutic agents to treat UPEC infection.
ESTHER : Pang_2022_Cell.Rep_39_110698
PubMedSearch : Pang_2022_Cell.Rep_39_110698
PubMedID: 35443182

Title : Toxic effects of glyphosate on the intestine, liver, brain of carp and on epithelioma papulosum cyprinid cells: Evidence from in vivo and in vitro research - Cao_2022_Chemosphere__134691
Author(s) : Cao X , Rao C , Cui H , Sun D , Li L , Guo S , Zhou J , Yuan R , Yang S , Chen J
Ref : Chemosphere , :134691 , 2022
Abstract : Glyphosate (GLY) is the most widely used organophosphorus herbicide in agriculture. The present study aimed to analyze the comprehensive toxicological effects of GLY on juvenile common carp and an epithelioma papulosum cyprinid (EPC) cell line. In the in vivo experiments, exposure to GLY (5 and 15 mg/L) for 30 days induced liver inflammation and oxidative damage in common carp and changed the physical barrier of the intestine. Histopathological analysis of the intestine, liver, brain, and changes in oxidative stress biomarkers provided evidence of damage and immune system responses to GLY. Moreover, an inhibitory effect of 15 mg/L GLY on acetylcholinesterase (AChE) activity was found in the brain, which may be an important reason for the significant decrease in both swimming distance and average acceleration of common carp. Cell experiments showed that 0.65 and 3.25 mg/L GLY inhibited the viability of EPCs. Furthermore, oxidative DNA damage, mitochondrial dysfunction, and reactive oxygen species (ROS) production were observed in EPC cells following GLY exposure. Taken together, this study not only highlights the negative effects of GLY on common carp but also enriches the knowledge of the cytotoxicity mechanism to further clarify the comprehensive toxicity of GLY in common carp.
ESTHER : Cao_2022_Chemosphere__134691
PubMedSearch : Cao_2022_Chemosphere__134691
PubMedID: 35489457

Title : Polar substitutions on the surface of a lipase substantially improve tolerance in organic solvents - Davari_2022_ChemSusChem__
Author(s) : Davari MD , Cui H , Vedder M , Zhang L , Jaeger KE , Schwaneberg U
Ref : ChemSusChem , : , 2022
Abstract : Biocatalysis in organic solvents (OSs) enables more efficient routes to the synthesis of various valuable chemicals. However, OSs often reduce enzymatic activity which limits the use enzymes in OSs. Herein, we report a comprehensive understanding of interactions between surface polar substitutions and DMSO by integrating the molecular dynamics (MD) simulations of 45 variants from Bacillus subtilis lipase A (BSLA) and substitution landscape in “BSLA-SSM library. By systematically analyzing 39 structural-, solvation-, and interaction energy-based observables, we discovered hydration shell maintenance, DMSO reduction, and decreased local flexibility simultaneously govern the stability of polar variants in OS. Moreover, the fingerprints of 1644 polar-related variants in three OSs demonstrated substituting aromatic to polar residue(s) hold great potential to highly improve OSs resistance. Hence, surface polar engineering enable to be a powerful and general strategy for generating OS-tolerant lipases and other enzymes, thereby adapting the catalyst to the desired reaction and process with OSs.
ESTHER : Davari_2022_ChemSusChem__
PubMedSearch : Davari_2022_ChemSusChem__
PubMedID: 35007408
Gene_locus related to this paper: bacsu-lip

Title : Using Molecular Simulation to Guide Protein Engineering for Biocatalysis in Organic Solvents - Cui_2022_Methods.Mol.Biol_2397_179
Author(s) : Cui H , Vedder M , Schwaneberg U , Davari MD
Ref : Methods Mol Biol , 2397 :179 , 2022
Abstract : Biocatalysis in organic solvents (OSs) is very appealing for the industry in producing bulk and/or fine chemicals, such as pharmaceuticals, biodiesel, and fragrances. The poor performance of enzymes in OSs (e.g., reduced activity, insufficient stability, and deactivation) negates OSs' excellent solvent properties. Molecular dynamics (MD) simulations provide a complementary method to study the relationship between enzymes dynamics and the stability in OSs. Here we describe computational procedure for MD simulation of enzymes in OSs with an example of Bacillus subtilis lipase A (BSLA) in dimethyl sulfoxide (DMSO) cosolvent with software GROMACS. We discuss main essential practical issues considered (such as choice of force field, parameterization, simulation setup, and trajectory analysis). The core part of this protocol (enzyme-OS system setup, analysis of structural-based and solvation-based observables) is transferable to other enzymes and any OS systems. Combining with experimental studies, the obtained molecular knowledge is most likely to guide researchers to access rational protein engineering approaches to tailor OS resistant enzymes and expand the scope of biocatalysis in OS media. Finally, we discuss potential solutions to overcome the remaining challenges of computational biocatalysis in OSs and briefly draw future directions for further improvement in this field.
ESTHER : Cui_2022_Methods.Mol.Biol_2397_179
PubMedSearch : Cui_2022_Methods.Mol.Biol_2397_179
PubMedID: 34813065
Gene_locus related to this paper: bacsu-lip

Title : Structural insights into catalytical capability for CPT11 hydrolysis and substrate specificity of a novel marine microbial carboxylesterase, E93 - Li_2022_Front.Microbiol_13_1081094
Author(s) : Li Y , Rong Z , Li Z , Cui H , Li J , Xu XW
Ref : Front Microbiol , 13 :1081094 , 2022
Abstract : INTRODUCTION: CPT11 (Irinotecan; 7-ethyl-10-[4-(1-piperidino)-1-piperidino] carbonyloxycamptothecin) is an important camptothecin-based broad-spectrum anticancer prodrug. The activation of its warhead, SN38 (7-ethyl-10-hydroxycamptothecin), requires hydrolysis by carboxylesterases. NPC (7-ethyl-10-[4-(1-piperidino)-1-amino] carbonyloxycamptothecin) is a metabolic derivative of CPT11 and is difficult to be hydrolyzed by human carboxylesterase. Microbial carboxylesterase with capability on both CPT11 and NPC hydrolysis is rarely reported. A marine microbial carboxylesterase, E93, was identified to hydrolyze both substrates in this study. This enzyme was an appropriate subject for uncovering the catalytic mechanism of carboxylesterases to CPT11 and NPC hydrolysis. METHODS: X-ray diffraction method was applied to obtain high-resolution structure of E93. Molecular docking was adopted to analyze the interaction of E93 with p-NP (p-nitrophenyl), CPT11, and NPC substrates. Mutagenesis and enzymatic assay were adopted to verify the binding pattern of substrates. RESULTS: Three core regions (Region A, B, and C) of the catalytic pocket were identified and their functions on substrates specificity were validated via mutagenesis assays. The Region A was involved in the binding with the alcohol group of all tested substrates. The size and hydrophobicity of the region determined the binding affinity. The Region B accommodated the acyl group of p-NP and CPT11 substrates. The polarity of this region determined the catalytic preference to both substrates. The Region C specifically accommodated the acyl group of NPC. The interaction from the acidic residue, E428, contributed to the binding of E93 with NPC. DISCUSSION: The study analyzed both unique and conserved structures of the pocket in E93, for the first time demonstrating the discrepancy of substrate-enzyme interaction between CPT11 and NPC. It also expanded the knowledge about the substrate specificity and potential application of microbial Family VII carboxylesterases.
ESTHER : Li_2022_Front.Microbiol_13_1081094
PubMedSearch : Li_2022_Front.Microbiol_13_1081094
PubMedID: 36756200

Title : Less unfavorable salt-bridges on the enzyme surface results in more organic cosolvent resistance - Cui_2021_Angew.Chem.Int.Ed.Engl__
Author(s) : Cui H , Eltoukhy L , Zhang L , Markel U , Jaeger KE , Davari MD , Schwaneberg U
Ref : Angew Chem Int Ed Engl , : , 2021
Abstract : Biocatalysis for the synthesis of fine chemicals is highly attractive but usually requires organic (co-)solvents (OSs). However, native enzymes often have low activity and resistance in OSs and at elevated temperatures. Herein, we report a smart salt bridge design strategy for simultaneously improving OS resistance and thermostability of the model enzyme, Bacillus subtilits Lipase A (BSLA). We combined comprehensive experimental studies of 3450 BSLA variants and molecular dynamics simulations of 36 systems. Iterative recombination of four beneficial substitutions yielded superior resistant variants with up to 7.6-fold (D64K/D144K) improved resistance toward three OSs while exhibiting significant thermostability (thermal resistance up to 137-fold, and half-life up to 3.3-fold). Molecular dynamics simulations revealed that locally refined flexibility and strengthened hydration jointly govern the highly increased resistance in OSs and at 50-100 degreesC. The salt bridge redesign provides protein engineers with a powerful and likely general approach to design OSs- and/or thermal-resistant lipases and other alpha/beta-hydrolases.
ESTHER : Cui_2021_Angew.Chem.Int.Ed.Engl__
PubMedSearch : Cui_2021_Angew.Chem.Int.Ed.Engl__
PubMedID: 33687787
Gene_locus related to this paper: bacsu-LIPB

Title : CompassR Yields Highly Organic-Solvent-Tolerant Enzymes through Recombination of Compatible Substitutions - Cui_2021_Chemistry_27_2789
Author(s) : Cui H , Jaeger KE , Davari MD , Schwaneberg U
Ref : Chemistry , 27 :2789 , 2021
Abstract : The CompassR (computer-assisted recombination) rule enables, among beneficial substitutions, the identification of those that can be recombined in directed evolution. Herein, a recombination strategy is systematically investigated to minimize experimental efforts and maximize possible improvements. In total, 15 beneficial substitutions from Bacillus subtilis lipaseA (BSLA), which improves resistance to the organic cosolvent 1,4-dioxane (DOX), were studied to compare two recombination strategies, the two-gene recombination process (2GenReP) and the in silico guided recombination process (InSiReP), employing CompassR. Remarkably, both strategies yielded a highly DOX-resistant variant, M4 (I12R/Y49R/E65H/N98R/K122E/L124K), with up to 14.6-fold improvement after screening of about 270 clones. M4 has a remarkably enhanced resistance in 60% (v/v) acetone (6.0-fold), 30% (v/v) ethanol (2.1-fold), and 60% (v/v) methanol (2.4-fold) compared with wild-type BSLA. Molecular dynamics simulations revealed that attracting water molecules by charged surface substitutions is the main driver for increasing the DOX resistance of BSLA M4. Both strategies and obtained molecular knowledge can likely be used to improve the properties of other enzymes with a similar alpha/beta-hydrolase fold.
ESTHER : Cui_2021_Chemistry_27_2789
PubMedSearch : Cui_2021_Chemistry_27_2789
PubMedID: 33186477

Title : Perilla frutescens Leaf Extract and Fractions: Polyphenol Composition, Antioxidant, Enzymes (alpha-Glucosidase, Acetylcholinesterase, and Tyrosinase) Inhibitory, Anticancer, and Antidiabetic Activities - Wang_2021_Foods_10_
Author(s) : Wang Z , Tu Z , Xie X , Cui H , Kong KW , Zhang L
Ref : Foods , 10 : , 2021
Abstract : This study aims to evaluate the bioactive components, in vitro bioactivities, and in vivo hypoglycemic effect of P. frutescens leaf, which is a traditional medicine-food homology plant. P. frutescens methanol crude extract and its fractions (petroleum ether, chloroform, ethyl acetate, n-butanol fractions, and aqueous phase residue) were prepared by ultrasound-enzyme assisted extraction and liquid-liquid extraction. Among the samples, the ethyl acetate fraction possessed the high total phenolic (440.48 microg GAE/mg DE) and flavonoid content (455.22 microg RE/mg DE), the best antioxidant activity (the DPPH radical, ABTS radical, and superoxide anion scavenging activity, and ferric reducing antioxidant power were 1.71, 1.14, 2.40, 1.29, and 2.4 times higher than that of control Vc, respectively), the most powerful alpha-glucosidase inhibitory ability with the IC(50) value of 190.03 microg/mL which was 2.2-folds higher than control acarbose, the strongest proliferative inhibitory ability against MCF-7 and HepG2 cell with the IC(50) values of 37.92 and 13.43 microg/mL, which were considerable with control cisplatin, as well as certain inhibition abilities on acetylcholinesterase and tyrosinase. HPLC analysis showed that the luteolin, rosmarinic acid, rutin, and catechin were the dominant components of the ethyl acetate fraction. Animal experiments further demonstrated that the ethyl acetate fraction could significantly decrease the serum glucose level, food, and water intake of streptozotocin-induced diabetic SD rats, increase the body weight, modulate their serum levels of TC, TG, HDL-C, and LDL-C, improve the histopathology and glycogen accumulation in liver and intestinal tissue. Taken together, P. frutescens leaf exhibits excellent hypoglycemic activity in vitro and in vivo, and could be exploited as a source of natural antidiabetic agent.
ESTHER : Wang_2021_Foods_10_
PubMedSearch : Wang_2021_Foods_10_
PubMedID: 33546380

Title : (+\/-)-Dievodialetins A-G: Seven pairs of enantiomeric coumarin dimers with anti-acetylcholinesterase activity from the roots of Evodia lepta Merr - Huang_2020_Phytochemistry_182_112597
Author(s) : Huang GY , Cui H , Lu XY , Zhang LD , Ding XY , Wu JJ , Duan LX , Zhang SJ , Liu Z , Zhang RR
Ref : Phytochemistry , 182 :112597 , 2020
Abstract : Seven pairs of undescribed enantiomeric bis-coumarins, (+/-)-dievodialetins A-G, were separated from the roots of Evodia lepta Merr. Two coumarin nuclei were linked via a 1,4-dimethyl4-vinylcyclohexene moiety in (+/-)-dievodialetins C-G. The structures of the undescribed compounds, including their absolute configurations were elucidated by spectroscopic analyses, X-ray diffraction, and computational calculations. In the biosynthetic pathways, these bis-coumarins were presumably derived from the precursors demethylsuberosin and 3-(3-methylbut-2-enyl)umbelliferone via a [4 + 2] Diels-Alder reaction. Besides, all compounds exhibited neuroprotective effects by inhibiting acetylcholinesterase (AChE) activity with IC(50) values ranging from 7.3 to 12.1 nM and they also suppressed oxidative stress (MDA and SOD) and neuroinflammation (IL-1beta and IL-6).
ESTHER : Huang_2020_Phytochemistry_182_112597
PubMedSearch : Huang_2020_Phytochemistry_182_112597
PubMedID: 33341030

Title : Comparative assessment of neurotoxicity impacts induced by alkyl tri-n-butyl phosphate and aromatic tricresyl phosphate in PC12 cells - Chang_2020_Environ.Toxicol_35_1326
Author(s) : Chang Y , Cui H , Jiang X , Li M
Ref : Environ Toxicol , 35 :1326 , 2020
Abstract : Organophosphate flame retardants (OPFRs) have become a growing concern due to their potential environmental and health risk. However, limited studies have described the toxicity, particularly neurotoxicity of alkyl and aromatic OPFRs. This study investigated the neurotoxicity of alkyl tri-n-butyl phosphate (TnBP) and aromatic tricresyl phosphate (TCP) to rat adrenal pheochromocytoma (PC12) cells for 24h. Viability detection showed dose-response toxicity effect of TCP and TnBP to PC12 cells. The half-maximal inhibitory concentration of 24h (24h-IC(50) ) of TCP and TnBP were 2415.61 and 338.09microM, respectively. Both TnBP and TCP significantly changed the acetylcholinesterase (AChE) activity, and TnBP is more likely to cause neurotoxicity to PC12 cells compared to TCP. Also, The results of LDH and caspase-3 activity detection as well as Hoechst staining suggested that cell apoptosis induced by TCP and TnBP may be the primary pathway. These findings provide a toxicity data of aromatic and alkyl-substituted OPFRs to PC12 cells, and a new insight into the toxicity of OPFRs on health risk assessment.
ESTHER : Chang_2020_Environ.Toxicol_35_1326
PubMedSearch : Chang_2020_Environ.Toxicol_35_1326
PubMedID: 32662595

Title : Polysaccharide from Spirulina platensis ameliorates diphenoxylate-induced constipation symptoms in mice - Ma_2019_Int.J.Biol.Macromol_133_1090
Author(s) : Ma H , Xiong H , Zhu X , Ji C , Xue J , Li R , Ge B , Cui H
Ref : Int J Biol Macromol , 133 :1090 , 2019
Abstract : The aim of this study is to probe new functions of a polysaccharide from Spirulina platensis (PSP) on constipation and intestinal microbiota in mice. Diphenoxylate-induced constipation in mice was treated with different doses of PSP, followed by examining the defecation patterns, levels of acetyl cholinesterase (AchE), nitric oxide (NO), and tissue section histopathology. The composition of intestinal microbiota was determined by genome sequencing analysis of the 16S rDNA. This study found that the average molecular weight of PSP was 29, 600Da, and mainly monosaccharides of PSP were rhamnose (24.7%), glucose (16.15%) and galactose (13.32%). The beneficial effects of PSP treatment include defecation improvement, increase of AchE activity, reduction of NO concentration, renovation of the damaged intestinal villus and affection on the expression of some related genes in the constipated mice. In addition, PSP had significant effects on the gut microbiota, showing the enhancement in abundance of beneficial bacteria including Akkermansia, Lactobacillus, Butyricimonas, Candidatus Arthromitus and Prevotella, and the reduction in abundance of harmful bacteria such as Clostridium and Dorea. The present s uncovered a new function of PSP, indicating that PSP could be used in constipation therapies.
ESTHER : Ma_2019_Int.J.Biol.Macromol_133_1090
PubMedSearch : Ma_2019_Int.J.Biol.Macromol_133_1090
PubMedID: 31054300

Title : Determinants and prediction of esterase substrate promiscuity patterns - Martinez-Martinez_2018_ACS.Chem.Biol_13_225
Author(s) : Martinez-Martinez M , Coscolin C , Santiago G , Chow J , Stogios PJ , Bargiela R , Gertler C , Navarro-Fernandez J , Bollinger A , Thies S , Mendez-Garcia C , Popovic A , Brown G , Chernikova TN , Garcia-Moyano A , Bjergah GE , Perez-Garcia P , Hai T , Del Pozo MV , Stokke R , Steen IH , Cui H , Xu X , Nocek BP , Alcaide M , Distaso M , Mesa V , Pelaez AI , Sanchez J , Buchholz PCF , Pleiss J , Fernandez-Guerra A , Glockner FO , Golyshina OV , Yakimov MM , Savchenko A , Jaeger KE , Yakunin AF , Streit WR , Golyshin PN , Guallar V , Ferrer M
Ref : ACS Chemical Biology , 13 :225 , 2018
Abstract : Esterases receive special attention because their wide distribution in biological systems and environments and their importance for physiology and chemical synthesis. The prediction of esterases substrate promiscuity level from sequence data and the molecular reasons why certain such enzymes are more promiscuous than others, remain to be elucidated. This limits the surveillance of the sequence space for esterases potentially leading to new versatile biocatalysts and new insights into their role in cellular function. Here we performed an extensive analysis of the substrate spectra of 145 phylogenetically and environmentally diverse microbial esterases, when tested with 96 diverse esters. We determined the primary factors shaping their substrate range by analyzing substrate range patterns in combination with structural analysis and protein-ligand simulations. We found a structural parameter that helps ranking (classifying) promiscuity level of esterases from sequence data at 94% accuracy. This parameter, the active site effective volume, exemplifies the topology of the catalytic environment by measuring the active site cavity volume corrected by the relative solvent accessible surface area (SASA) of the catalytic triad. Sequences encoding esterases with active site effective volumes (cavity volume/SASA) above a threshold show greater substrate spectra, which can be further extended in combination with phylogenetic data. This measure provides also a valuable tool for interrogating substrates capable of being converted. This measure, found to be transferred to phosphatases of the haloalkanoic acid dehalogenase superfamily and possibly other enzymatic systems, represents a powerful tool for low-cost bioprospecting for esterases with broad substrate ranges, in large scale sequence datasets.
ESTHER : Martinez-Martinez_2018_ACS.Chem.Biol_13_225
PubMedSearch : Martinez-Martinez_2018_ACS.Chem.Biol_13_225
PubMedID: 29182315
Gene_locus related to this paper: 9zzzz-a0a2k8jn75 , 9zzzz-a0a2k8jt94 , 9zzzz-a0a0g3fj44 , 9zzzz-a0a0g3fh10 , 9zzzz-a0a0g3fh03 , 9bact-a0a1s5qkj8 , 9zzzz-a0a0g3feh5 , 9zzzz-a0a0g3fkz4 , 9zzzz-a0a0g3fh07 , 9zzzz-a0a0g3fh34 , 9zzzz-a0a0g3fh31 , 9bact-KY458167 , alcbs-q0vqa3 , 9bact-a0a1s5qki8 , 9zzzz-a0a0g3feq8 , 9zzzz-a0a0g3feh8 , 9zzzz-a0a0g3fh19 , 9bact-KY203037 , 9bact-a0a1s5ql22 , 9bact-a0a1s5qm34 , 9bact-KY203034 , 9bact-r9qzg0 , 9bact-a0a1s5qly8 , 9zzzz-a0a0g3fkz8 , 9zzzz-a0a0g3feg9 , 9zzzz-KY203033 , 9zzzz-a0a0g3fes4 , 9zzzz-a0a0g3fh42 , 9bact-a0a1s5qlx2 , 9zzzz-KY483651 , 9bact-a0a1s5qmh4 , 9zzzz-KY203032 , 9zzzz-EH87 , 9zzzz-a0a0g3fei1 , 9zzzz-a0a0g3fet2 , 9zzzz-KY483647 , 9zzzz-EH82 , 9zzzz-a0a0g3fe15 , 9bact-KY203031 , 9bact-t1w006 , 9zzzz-a0a0g3fet6 , 9bact-KY458164 , geoth-g8myf3 , 9bact-a0a1s5ql04 , 9gamm-a0a1y0ihk7 , 9bact-a0a1s5qly6 , 9bact-a0a1s5qkg4 , 9bact-a0a1s5qkm4 , 9gamm-s5tv80 , 9gamm-a0a0c4zhg2 , 9zzzz-t1b379 , 9gamm-KY483646 , 9bact-KY458160 , 9zzzz-a0a0g3fj57 , 9gamm-s5t8349 , 9arch-KY203036 , 9bact-KY458168 , 9zzzz-a0a0g3fes0 , 9zzzz-t1be47 , 9bact-KY458159 , 9zzzz-a0a0g3fh39 , 9bact-t1vzd5 , 9prot-EH41 , 9bact-Lip114 , alcbs-q0vt77 , 9bact-a0a1s5qke6 , 9bact-a0a1s5qkf3 , 9prot-SRP030024 , 9gamm-s5t532 , 9bact-a0a1s5qkl2 , 9bact-a0a1s5qkk8 , 9zzzz-KY203030 , 9zzzz-t1d4I7 , 9prot-KY019260 , 9bact-a0a1s5qm38 , 9arch-KY458161 , 9prot-KY010302 , 9zzzz-a0a0g3fl25 , 9actn-KY010298 , 9gamm-s5u059 , 9bact-a0a1s5qmi7 , 9bact-KY010297 , 9bact-KY483642 , 9bact-a0a1s5qkj1 , 9bact-KY010299 , 9bact-KY483648 , alcbs-q0vtl7 , 9bact-a0a1s5qf1 , 9bact-a0a1s5qkg0 , 9bact-a0a0h4tgu6 , 9bact-MilE3 , 9bact-LAE6 , 9alte-MGS-MT1 , 9bact-r9qzf7 , 9gamm-k0c6t6 , alcbs-q0vl36 , alcbs-q0vlq1 , alcbs-q0vq49 , bacsu-pnbae , canar-LipB , canan-lipasA , geost-lipas , marav-a1u5n0 , pseps-i7k8x5 , staep-GEHD , symth-q67mr3 , altma-s5cfn7 , cycsp-k0c2b8 , alcbs-q0vlk5 , 9bact-k7qe48 , 9bact-MGS-M1 , 9bact-MGS-M2 , 9bact-a0a0b5kns5 , 9zzzz-a0a0g3fej4 , 9zzzz-a0a0g3fj60 , 9zzzz-a0a0g3fej0 , 9zzzz-a0a0g3fj64 , 9bact-a0a0b5kc16 , 9zzzz-a0a0g3feg6 , 9zzzz-a0a0g3feu6

Title : Antagonism of Transcription Factor MYC2 by EDS1\/PAD4 Complexes Bolsters Salicylic Acid Defense in Arabidopsis Effector-Triggered Immunity - Cui_2018_Mol.Plant_11_1053
Author(s) : Cui H , Qiu J , Zhou Y , Bhandari DD , Zhao C , Bautor J , Parker JE
Ref : Mol Plant , 11 :1053 , 2018
Abstract : In plant immunity, pathogen-activated intracellular nucleotide binding/leucine rich repeat (NLR) receptors mobilize disease resistance pathways, but the downstream signaling mechanisms remain obscure. Enhanced disease susceptibility 1 (EDS1) controls transcriptional reprogramming in resistance triggered by Toll-Interleukin1-Receptor domain (TIR)-family NLRs (TNLs). Transcriptional induction of the salicylic acid (SA) hormone defense sector provides one crucial barrier against biotrophic pathogens. Here, we present genetic and molecular evidence that in Arabidopsis an EDS1 complex with its partner PAD4 inhibits MYC2, a master regulator of SA-antagonizing jasmonic acid (JA) hormone pathways. In the TNL immune response, EDS1/PAD4 interference with MYC2 boosts the SA defense sector independently of EDS1-induced SA synthesis, thereby effectively blocking actions of a potent bacterial JA mimic, coronatine (COR). We show that antagonism of MYC2 occurs after COR has been sensed inside the nucleus but before or coincident with MYC2 binding to a target promoter, pANAC019. The stable interaction of PAD4 with MYC2 in planta is competed by EDS1-PAD4 complexes. However, suppression of MYC2-promoted genes requires EDS1 together with PAD4, pointing to an essential EDS1-PAD4 heterodimer activity in MYC2 inhibition. Taken together, these results uncover an immune receptor signaling circuit that intersects with hormone pathway crosstalk to reduce bacterial pathogen growth.
ESTHER : Cui_2018_Mol.Plant_11_1053
PubMedSearch : Cui_2018_Mol.Plant_11_1053
PubMedID: 29842929

Title : Screening and Characterization of Novel Polyesterases from Environmental Metagenomes with High Hydrolytic Activity against Synthetic Polyesters - Hajighasemi_2018_Environ.Sci.Technol_52_12388
Author(s) : Hajighasemi M , Tchigvintsev A , Nocek B , Flick R , Popovic A , Hai T , Khusnutdinova AN , Brown G , Xu X , Cui H , Anstett J , Chernikova TN , Bruls T , Le Paslier D , Yakimov MM , Joachimiak A , Golyshina OV , Savchenko A , Golyshin PN , Edwards EA , Yakunin AF
Ref : Environ Sci Technol , 52 :12388 , 2018
Abstract : The continuous growth of global plastics production, including polyesters, has resulted in increasing plastic pollution and subsequent negative environmental impacts. Therefore, enzyme-catalyzed depolymerization of synthetic polyesters as a plastics recycling approach has become a focus of research. In this study, we screened over 200 purified uncharacterized hydrolases from environmental metagenomes and sequenced microbial genomes and identified at least 10 proteins with high hydrolytic activity against synthetic polyesters. These include the metagenomic esterases MGS0156 and GEN0105, which hydrolyzed polylactic acid (PLA), polycaprolactone, as well as bis(benzoyloxyethyl)-terephthalate. With solid PLA as a substrate, both enzymes produced a mixture of lactic acid monomers, dimers, and higher oligomers as products. The crystal structure of MGS0156 was determined at 1.95 A resolution and revealed a modified alpha/beta hydrolase fold, with a lid domain and highly hydrophobic active site. Mutational studies of MGS0156 identified the residues critical for hydrolytic activity against both polyester and monoester substrates, with two-times higher polyesterase activity in the MGS0156 L169A mutant protein. Thus, our work identified novel, highly active polyesterases in environmental metagenomes and provided molecular insights into their activity, thereby augmenting our understanding of enzymatic polyester hydrolysis.
ESTHER : Hajighasemi_2018_Environ.Sci.Technol_52_12388
PubMedSearch : Hajighasemi_2018_Environ.Sci.Technol_52_12388
PubMedID: 30284819
Gene_locus related to this paper: 9zzzz-a0a0g3fj39 , 9zzzz-a0a0g3fj48 , 9zzzz-A0A0G3FEJ8 , 9bact-a4uz10

Title : A core function of EDS1 with PAD4 is to protect the salicylic acid defense sector in Arabidopsis immunity - Cui_2017_New.Phytol_213_1802
Author(s) : Cui H , Gobbato E , Kracher B , Qiu J , Bautor J , Parker JE
Ref : New Phytol , 213 :1802 , 2017
Abstract : Plant defenses induced by salicylic acid (SA) are vital for resistance against biotrophic pathogens. In basal and receptor-triggered immunity, SA accumulation is promoted by Enhanced Disease Susceptibility1 with its co-regulator Phytoalexin Deficient4 (EDS1/PAD4). Current models position EDS1/PAD4 upstream of SA but their functional relationship remains unclear. In a genetic and transcriptomic analysis of Arabidopsis autoimmunity caused by constitutive or conditional EDS1/PAD4 overexpression, intrinsic EDS1/PAD4 signaling properties and their relation to SA were uncovered. A core EDS1/PAD4 pathway works in parallel with SA in basal and effector-triggered bacterial immunity. It protects against disabled SA-regulated gene expression and pathogen resistance, and is distinct from a known SA-compensatory route involving MAPK signaling. Results help to explain previously identified EDS1/PAD4 regulated SA-dependent and SA-independent gene expression sectors. Plants have evolved an alternative route for preserving SA-regulated defenses against pathogen or genetic perturbations. In a proposed signaling framework, EDS1 with PAD4, besides promoting SA biosynthesis, maintains important SA-related resistance programs, thereby increasing robustness of the innate immune system.
ESTHER : Cui_2017_New.Phytol_213_1802
PubMedSearch : Cui_2017_New.Phytol_213_1802
PubMedID: 27861989

Title : Acetylcholinesterase Inhibitory Meroterpenoid from a Mangrove Endophytic Fungus Aspergillus sp. 16-5c - Long_2017_Molecules_22_
Author(s) : Long Y , Cui H , Liu X , Xiao Z , Wen S , She Z , Huang X
Ref : Molecules , 22 : , 2017
Abstract : One new meroterpenoid, named 2-hydroacetoxydehydroaustin (1), together with nine known meroterpenoids, 11-acetoxyisoaustinone (2), isoaustinol (3), austin (4), austinol (5), acetoxydehydroaustin (6), dehydroaustin (7), dehydroaustinol (8), preaustinoid A2 (9), and 1,2-dihydro-acetoxydehydroaustin B (10), were isolated from the mangrove endophytic fungus, Aspergillus sp. 16-5c. These structures were characterized by spectroscopic analysis, further the absolute configurations of stereogenic carbons for Compounds 1, 3, 4, 6, 7, 8, 9, and 10 were determined by single crystal X-ray diffraction analysis using Cu Kalpha radiation. Moreover, the absolute configurations of stereogenic carbons for Known Compounds 3, 7, 8, and 9 are identified here for the first time. Compounds 3, 7, and 8 showed acetylcholinesterase (AchE) inhibitory activity with IC50 values of 2.50, 0.40, and 3.00 muM, respectively.
ESTHER : Long_2017_Molecules_22_
PubMedSearch : Long_2017_Molecules_22_
PubMedID: 28467349

Title : Biochemical and Structural Insights into Enzymatic Depolymerization of Polylactic Acid and Other Polyesters by Microbial Carboxylesterases - Hajighasemi_2016_Biomacromolecules_17_2027
Author(s) : Hajighasemi M , Nocek BP , Tchigvintsev A , Brown G , Flick R , Xu X , Cui H , Hai T , Joachimiak A , Golyshin PN , Savchenko A , Edwards EA , Yakunin AF
Ref : Biomacromolecules , 17 :2027 , 2016
Abstract : Polylactic acid (PLA) is a biodegradable polyester derived from renewable resources, which is a leading candidate for the replacement of traditional petroleum-based polymers. Since the global production of PLA is quickly growing, there is an urgent need for the development of efficient recycling technologies, which will produce lactic acid instead of CO2 as the final product. After screening 90 purified microbial alpha/beta-hydrolases, we identified hydrolytic activity against emulsified PLA in two uncharacterized proteins, ABO2449 from Alcanivorax borkumensis and RPA1511 from Rhodopseudomonas palustris. Both enzymes were also active against emulsified polycaprolactone and other polyesters as well as against soluble alpha-naphthyl and p-nitrophenyl monoesters. In addition, both ABO2449 and RPA1511 catalyzed complete or extensive hydrolysis of solid PLA with the production of lactic acid monomers, dimers, and larger oligomers as products. The crystal structure of RPA1511 was determined at 2.2 A resolution and revealed a classical alpha/beta-hydrolase fold with a wide-open active site containing a molecule of polyethylene glycol bound near the catalytic triad Ser114-His270-Asp242. Site-directed mutagenesis of both proteins demonstrated that the catalytic triad residues are important for the hydrolysis of both monoester and polyester substrates. We also identified several residues in RPA1511 (Gln172, Leu212, Met215, Trp218, and Leu220) and ABO2449 (Phe38 and Leu152), which were not essential for activity against soluble monoesters but were found to be critical for the hydrolysis of PLA. Our results indicate that microbial carboxyl esterases can efficiently hydrolyze various polyesters making them attractive biocatalysts for plastics depolymerization and recycling.
ESTHER : Hajighasemi_2016_Biomacromolecules_17_2027
PubMedSearch : Hajighasemi_2016_Biomacromolecules_17_2027
PubMedID: 27087107
Gene_locus related to this paper: marav-a1u5n0 , rhopa-q6n9m9 , alcbs-q0vlq1

Title : The N-terminal fragment of the beta-amyloid precursor protein of Alzheimer's disease (N-APP) binds to phosphoinositide-rich domains on the surface of hippocampal neurons - Dawkins_2014_J.Neurosci.Res_92_1478
Author(s) : Dawkins E , Gasperini R , Hu Y , Cui H , Vincent AJ , Bolos M , Young KM , Foa L , Small DH
Ref : Journal of Neuroscience Research , 92 :1478 , 2014
Abstract : The function of the beta-amyloid precursor protein (APP) of Alzheimer's disease is poorly understood. The secreted ectodomain fragment of APP (sAPPalpha) can be readily cleaved to produce a small N-terminal fragment (N-APP) that contains heparin-binding and metal-binding domains and that has been found to have biological activity. In the present study, we examined whether N-APP can bind to lipids. We found that N-APP binds selectively to phosphoinositides (PIPs) but poorly to most other lipids. Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2 )-rich microdomains were identified on the extracellular surface of neurons and glia in primary hippocampal cultures. N-APP bound to neurons and colocalized with PIPs on the cell surface. Furthermore, the binding of N-APP to neurons increased the level of cell-surface PI(4,5)P2 and phosphatidylinositol 3,4,5-trisphosphate. However, PIPs were not the principal cell-surface binding site for N-APP, because N-APP binding to neurons was not inhibited by a short-acyl-chain PIP analogue, and N-APP did not bind to glial cells which also possessed PI(4,5)P2 on the cell surface. The data are explained by a model in which N-APP binds to two distinct components on neurons, one of which is an unidentified receptor and the second of which is a PIP lipid, which binds more weakly to a distinct site within N-APP. Our data provide further support for the idea that N-APP may be an important mediator of APP's biological activity.
ESTHER : Dawkins_2014_J.Neurosci.Res_92_1478
PubMedSearch : Dawkins_2014_J.Neurosci.Res_92_1478
PubMedID: 24916405

Title : Discovery of dipeptidyl peptidase IV (DPP4) inhibitors based on a novel indole scaffold - Xiao_2014_Chin.Chem.Lett_25_673
Author(s) : Xiao P , Guo R , Huang S , Cui H , Ye S , Zhang Z
Ref : Chin Chem Lett , 25 :673 , 2014
Abstract : Dipeptidyl peptidase IV (DPP4) inhibitors are proven in the treatment of type 2 diabetes. We designed and synthesized a series of novel indole compounds that selectively inhibit the activity of DPP4 over dipeptidyl peptidase 9 (DPP9) (>200 fold). We further co-crystallized DPP4 with indole sulfonamide (compound 1) to confirm a proposed binding mode. Good metabolic stability of the indole compounds represents another positive attribute for further development.
ESTHER : Xiao_2014_Chin.Chem.Lett_25_673
PubMedSearch : Xiao_2014_Chin.Chem.Lett_25_673
PubMedID:
Gene_locus related to this paper: human-DPP4

Title : Proteoglycans in the central nervous system: role in development, neural repair, and Alzheimer's disease - Cui_2013_IUBMB.Life_65_108
Author(s) : Cui H , Freeman C , Jacobson GA , Small DH
Ref : IUBMB Life , 65 :108 , 2013
Abstract : Proteoglycans (PGs) are major components of the cell surface and extracellular matrix and play critical roles in development and maintenance of the central nervous system (CNS). PGs are a family of proteins, all of which contain a core protein to which glycosaminoglycan side chains are covalently attached. PGs possess diverse physiological roles, particularly in neural development, and are also implicated in the pathogenesis of neurodegenerative diseases such as Alzheimer's disease (AD). The main functions of PGs in the CNS are reviewed as are the roles of PGs in brain injury and in the development or treatment of AD.
ESTHER : Cui_2013_IUBMB.Life_65_108
PubMedSearch : Cui_2013_IUBMB.Life_65_108
PubMedID: 23297096

Title : An inserted alpha\/beta subdomain shapes the catalytic pocket of Lactobacillus johnsonii cinnamoyl esterase - Lai_2011_PLoS.One_6_e23269
Author(s) : Lai KK , Stogios PJ , Vu C , Xu X , Cui H , Molloy S , Savchenko A , Yakunin A , Gonzalez CF
Ref : PLoS ONE , 6 :e23269 , 2011
Abstract : BACKGROUND: Microbial enzymes produced in the gastrointestinal tract are primarily responsible for the release and biochemical transformation of absorbable bioactive monophenols. In the present work we described the crystal structure of LJ0536, a serine cinnamoyl esterase produced by the probiotic bacterium Lactobacillus johnsonii N6.2. METHODOLOGY/PRINCIPAL FINDINGS: We crystallized LJ0536 in the apo form and in three substrate-bound complexes. The structure showed a canonical alpha/beta fold characteristic of esterases, and the enzyme is dimeric. Two classical serine esterase motifs (GlyXSerXGly) can be recognized from the amino acid sequence, and the structure revealed that the catalytic triad of the enzyme is formed by Ser(106), His(225), and Asp(197), while the other motif is non-functional. In all substrate-bound complexes, the aromatic acyl group of the ester compound was bound in the deepest part of the catalytic pocket. The binding pocket also contained an unoccupied area that could accommodate larger ligands. The structure revealed a prominent inserted alpha/beta subdomain of 54 amino acids, from which multiple contacts to the aromatic acyl groups of the substrates are made. Inserts of this size are seen in other esterases, but the secondary structure topology of this subdomain of LJ0536 is unique to this enzyme and its closest homolog (Est1E) in the Protein Databank. CONCLUSIONS: The binding mechanism characterized (involving the inserted alpha/beta subdomain) clearly differentiates LJ0536 from enzymes with similar activity of a fungal origin. The structural features herein described together with the activity profile of LJ0536 suggest that this enzyme should be clustered in a new group of bacterial cinnamoyl esterases.
ESTHER : Lai_2011_PLoS.One_6_e23269
PubMedSearch : Lai_2011_PLoS.One_6_e23269
PubMedID: 21876742
Gene_locus related to this paper: lacjo-q74hk5

Title : Liver-specific deletion of the NADPH-cytochrome P450 reductase gene: impact on plasma cholesterol homeostasis and the function and regulation of microsomal cytochrome P450 and heme oxygenase - Gu_2003_J.Biol.Chem_278_25895
Author(s) : Gu J , Weng Y , Zhang QY , Cui H , Behr M , Wu L , Yang W , Zhang L , Ding X
Ref : Journal of Biological Chemistry , 278 :25895 , 2003
Abstract : A mouse model with liver-specific deletion of the NADPH-cytochrome P450 reductase (Cpr) gene (designated Alb-Cre/Cprlox mice) was generated and characterized in this study. Hepatic microsomal CPR expression was significantly reduced at 3 weeks and was barely detectable at 2 months of age in the Alb-Cre+/-/Cprlox+/+ (homozygous) mice, with corresponding decreases in liver microsomal cytochrome P450 (CYP) and heme oxygenase (HO) activities, in pentobarbital clearance, and in total plasma cholesterol level. Nevertheless, the homozygous mice are fertile and are normal in gross appearance and growth rate. However, at 2 months, although not at 3 weeks, the homozygotes had significant increases in liver weight, accompanied by hepatic lipidosis and other pathologic changes. Intriguingly, total microsomal CYP content was increased in the homozygotes about 2-fold at 3 weeks and about 3-fold at 2 months of age; at 2 months, there were varying degrees of induction in protein (1-5-fold) and mRNA expression (0-67-fold) for all CYPs examined. There was also an induction of HO-1 protein (nearly 9-fold) but no induction of HO-2. These data indicate the absence of significant alternative redox partners for liver microsomal CYP and HO, provide in vivo evidence for the significance of hepatic CPR-dependent enzymes in cholesterol homeostasis and systemic drug clearance, and reveal novel regulatory pathways of CYP expression associated with altered cellular homeostasis. The Alb-Cre/Cprlox mouse represents a unique model for studying the in vivo function of hepatic HO and microsomal CYP-dependent pathways in the biotransformation of endogenous and xenobiotic compounds.
ESTHER : Gu_2003_J.Biol.Chem_278_25895
PubMedSearch : Gu_2003_J.Biol.Chem_278_25895
PubMedID: 12697746