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Bioactive Hydrogels with Pro-coagulation Effect for Hemostasis

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Chinese Journal of Chemistry 2024年第1期42卷 87-103,I0004页

作者： Quanshi Guo Yihang Ding Lisha Yu Zongrui Tong Zhengwei Mao MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhouZhejiang 310058China Department of Hepatobiliary and Pancreatic Surgery The Second Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhouZhejiang 310009China Key Laboratory of Precision Diagnosis and Treatment for Hepatobiliary and Pancreatic Tumor of Zhejiang Province HangzhouZhejiang 310009China

Hemostatic hydrogels are widely applied for wound management of damaged tissues,traumatic wounds,and surgical incisions.Some hydrogels composed of bioactive components,including fibrin and thrombin,showed great promise in the clinic due to their good pro-coagulation effect.With the expanding knowledge of cascade reaction of blood coagulation and emerging bioactive substances,massive bioactive hydrogels consisting of peptides,hemocoagulase,polyphosphate(polyP),etc.,have been developed as effective hemostatic materials.Based on the coagulation process and mechanism,we summarize the role of reported bioactive hydrogels in hemostasis in this review.We conclude the key points in the coagulation process,including activation of coagulation factors,fibrinogen polymerization,etc.,then discuss how to design bioactive hydrogels to accelerate coagulation targeted to these points.Finally,we conclude the progress and propose a perspective of bioactive hydrogels with a pro-coagulation effect for hemostasis.

关键词： Hemostasis Biological activity Biomaterials Enzyme catalysis Composites

Establishing Modular Cell-Free Expression System for the Biosynthesis of Bicyclomycin from a Chemically Synthesized Cyclodipeptide

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Chinese Journal of Chemistry 2024年第4期42卷 384-390页

作者： Yi-Pei Liu Yu-Heng Zhao Wen-Qi Zhang Lian Wu Linjuan Huang Gong-Li Tang Jun-Bin He Shaanxi Natural Carbohydrate Resource Engineering Research Center College of Food Science and TechnologyNorthwest UniversityXi'anShaanxi710069 China State Key Laboratory of Chemical Biology Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of Sciences(CAS)CASShanghai200032 China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of CAS1 Sub-lane XiangshanHangzhouZhejiang310024 China

Cell-free expression systems have emerged as a versatile and powerful platform for metabolic engineering,biosynthesis and synthetic biology studies.Nevertheless,successful examples of the synthesis of complex natural products using this system are still limited.Bicyclomycin,a structurally unique and complex diketopiperazine alkaloid,is a clinically promising antibiotic that selectively inhibits the transcription termination factor Rho.Here,we established a modular cell-free expression system with cascade catalysis for the biosynthesis of bicyclomycin from a chemically synthesized cyclodipeptide.The six cell-free expressed biosynthetic enzymes,including five iron-andα-ketoglutarate-dependent dioxygenases and one cytochrome P450 monooxygenase,were active in converting their substrates to the corresponding products.The co-expressed enzymes in the cell-free module were able to complete the related partial pathway.In vitro biosynthesis of bicyclomycin was also achieved by reconstituting the entire biosynthetic pathways(i.e.,six enzymes)using the modular cell-free expression system.This study demonstrates that the modular cell-free expression system can be used as a robust and promising platformforthe biosynthesis of complex antibiotics.

关键词： Natural products Bicyclomycin Biosynthesis Iron-andα-ketoglutarate-dependent dioxygenases Cytochrome P450 monooxygenase Cell-freeprotein synthesis Enzyme catalysis

A Bacterial Cytochrome P450 enzyme Catalyzes Multistep Oxidation Reactions in Pyrroindomycin Biosynthesis

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Chinese Journal of Chemistry 2023年第19期41卷 2439-2445页

作者： Jiabao Wang Yu Xu Dandan Chen Jiang Tao Hongbo Wang Wen Liu Department of Chemistry Shanghai Normal University100 Guiling RoadShanghai200233 China State Key Laboratory of Bioorganic and Natural Products Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of Sciences345 Lingling RoadShanghai200032 China Department of General Dentistry Shanghai Ninth People's HospitalShanghai Jiao Tong University School of MedicineCollege of StomatologyShanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghai Research Institute of Stomatology639 Zhizaoju RoadShanghai200011 China

Cytochrome P450 enzymes (P450s) belong to a large family of oxidative hemeproteins and catalyze highly diverse oxygenation reactions that are involved in the biosynthesis of various natural products. Here, we report a multifunctional cytochrome P450 enzyme, PyrE2, which catalyzes the regioselective, successive 6-electron oxidation of an inert methyl group to produce a carboxyl product through formation of the hydroxyl and aldehyde intermediates in pyrroindomycin biosynthesis. The time-course biotransformation was characterized by the presence of the hydroxyl and aldehyde intermediates, the lag of the formation of the carboxyl product, and the subsequent loss of both intermediates, indicating that each 2-electron oxidation exhibits the distributive mechanism that requires substrate binding and product releasing. Bioinformatics analysis shows that the homologs of pyrE2 are common in the gene clusters of the spirotetronates varying in the oxidative state of the corresponding exocyclic carbon, indicating the generality and diversity of P450-catalyzed oxygenation in related biosynthetic pathways.

关键词： Cytochrome P450 enzyme Pyrroindomycin Multistep oxidation reactions Enzyme catalysis Selectivity

Sequential One-Pot Three-enzyme Synthesis of the Tetrasaccharide Repeating Unit of Group B Streptococcus Serotype Ⅷ Capsular Polysaccharide

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Chinese Journal of Chemistry 2022年第9期40卷 1039-1044页

作者： Min Liang Wei Gong Chongzhen Sun Jielin Zhao Hong Wang Zonggang Chen Min Xiao Guofeng Gu National Glycoengineering Research Center Shandong Provincial Key Laboratory of Carbohydrate Chemistry and GlycobiologyShandong University72 Binhai RoadQingdaoShandong 266237China School of Pharmaceutical Science Shandong University44 West Wenhua RoadJinanShandong 250012China NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate-based Medicine Shandong UniversityQingdaoShandong 266237china

The biochemical property and functional identification of three recombinant glycosyltransferases,includingβ-1,4-rhamnosyltransferase(Cps8R),β-1,4-galactosyltransferase(Cps8) and α-2,3-sialyltransferase(Cps8K)involved in the biosynthesis of the tetrasaccharide repeating unit of serotypeⅧcapsular polysaccharide(CPS)of Group B Streptococci(GBS),were systematically investigated.Subsequently,these recombinant enzymes were employed for one-pot three-enzyme efficient synthesis of the tetrasaccharide repeating unit of GBS serotypeⅧCPS using the chemically synthesized Glca-PP-(CH2)ir-OPh as the starting substrate in a satisfying yieldof 87%.

关键词： Streptococcus agalactiae Capsular polysaccharide Oligosaccharides Enzyme catalysis Biosynthesis

Continuous-flow synthesis of polysubstituted γ-butyrolactones via enzymatic cascade catalysis

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Chinese Chemical Letters 2024年第4期35卷 404-408页

作者： Liliang Chu Xiaoyan Zhang Jianing Li Xuelei Deng Miao Wu Ya Cheng Weiping Zhu Xuhong Qian Yunpeng Bai State Key Laboratory of Bioreactor Engineering Shanghai Collaborative Innovation Center for BiomanufacturingEast China University of Science and TechnologyShanghai 200237China The Extreme Optoelectromechanics Laboratory School of Physics and Materials ScienceEast China Normal UniversityShanghai 200241China

Polysubstituted chiral γ-butyrolactones are the core structural units of many natural products and high value-added flavors and fragrances used in the food and cosmetic industry. Current enzymatic cascade synthesis of these molecules faces the problems of low enzyme activity and phase separation in batch reaction, resulting in low productivity. Herein, we report a new continuous-flow process to synthesize the optically pure Nicotiana tabacum lactone(3S,4S)-4a and whisky lactone(3R,4S)-4b from α,β-unsaturatedγ-ketoesters. A new ene reductase(ER) from Swingsia samuiensi(Ss ER) and a carbonyl reductase(Ss CR)were engineered by directed evolution to improve their activity and thermostability. The continuous-flow preparative reactions were performed in two 3D microfluidic reactors, generating(3S,4S)-4a(99% ee and87% de) and(3R,4S)-4b(99% ee and 98% de) with space-time yields 3 and 7.4 times higher than those of the batch reactions. The significant enhancement in the productivity of enzyme cascade catalysis brought by cutting-edge continuous microfluidic technology will benefit the general multi-enzyme catalytic systems in the future.

关键词： Enzyme catalysis Cascade catalysis Directed evolution Continuous-flow γ-Butyrolactones

Characterization and application of a recombinant dopa decarboxylase from Harmonia axyridis for the efficient biosynthesis of dopamine

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Chinese Journal of Chemical Engineering 2022年第1期35卷 449-456页

作者： Siyuan Gao Yuanke Guo Chen Ma Ding Ma Kequan Chen Pingkai Ouyang Xin Wang State Key Laboratory of Materials-Oriented Chemical Engineering College of Biotechnology and Pharmaceutical EngineeringNanjing Tech UniversityNanjing 211816China

Here,a dopa decarboxylase(DDC)from Harmonia axyridis was heterogeneously expressed in Escherichia coli for the efficient biosynthesis of dopamine.For the production of recombinant DDC,the cultivation conditions including IPTG concentration,temperature and induction time were optimized and obtained an optimal specific enzyme activity of 51.72 U·mg^(-1) crude extracts.After the purification of DDC with a recovery yield of 68.79%,its activity was further characterized.The Vmax,Km,Kcat,and Kcat/Km of DDC for d ihyd roxy pheny la la nine(dopa)were 0.02 mmol·ml^(-1)·s^(-1),2.328 mmol·ml^(-1),10435.90 s^(-1) and4482.77 ml,mmol respectively.The highest DDC activity was observed at the condition of pH 7.5 and 45℃.With the purified DDC,the feasibility to produce dopamine from L-dopa was evaluated.The optimal yield was determined at the following bioconversion conditions:pH of 7,0,the reaction temperature of 40℃,0.4 mmol·L^(-1) of PLP and 4 g·L^(-1) of L-dopa,Subsequently,a fed-batch process for the production of dopamine was developed and the effect of oxygen was evaluated.The titer,yield and productivity of dopamine reached up to 21.99 g·L^(-1)80.88%and 14.66 g·L^(-1)·h^(-1) at 90 min under anaerobic condition.

关键词： Dopa decarboxylase Dopamine Enzyme catalysis Fed-batch bioconversion

Substrate specificity and reaction directionality of a three-residue cyclophane forming enzyme Pau B

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Chinese Chemical Letters 2023年第1期34卷 362-366页

作者： Yuanjun Han Suze Ma Qi Zhang Department of Chemistry Fudan UniversityShanghai 200433China

Three-residue cyclophane-forming enzymes(3-Cy FEs) are a group of radical S-adenosylmethionine(SAM)enzymes involved in the biosynthesis of ribosomally synthesized and posttranslationally modified peptides(Ri PPs). 3-Cy FE catalyzes the crosslinking between an aromatic residue(Ω1) and a non-aromatic residue(X3) in a Ω1-X2-X3 motif to produce a cyclophane ring, a key step in the biosynthesis of the Ri PP natural product triceptide. In this study, we perform a genome-wide search for the Xye-type triceptides, showing these Ri PPs are likely class-specific and only present in gamma-proteobacteria. The 3-Cy FE Pau B from Photorhabdus australis exhibits a relaxed substrate specificity on the X3 position, but glycine in this position is not suitable for cyclophane formation. We also reconstituted the activity of Pau B in vitro,showing it produces the N-terminal cyclophane firstly, and then the C-terminal ring, whereas the middle cyclophane is produced in the last step.

关键词： Cyclophane Biosynthesis Radical SAM Enzyme catalysis Peptide Natural product

Mechanism of allosteric activation of SIRT6 revealed by the action of rationally designed activators

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Acta Pharmaceutica Sinica B 2021年第5期11卷 1355-1361页

作者： Shaoyong Lu Yingyi Chen Jiacheng Wei Mingzhu Zhao Duan Ni Xinheng He Jian Zhang Department of Pathophysiology Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of EducationShanghai Jiao Tong UniversitySchool of MedicineShanghai 200025China State Key Laboratory of Oncogenes and Related Genes Renji HospitalShanghai Jiao Tong UniversitySchool of MedicineShanghai 200127China The Charles Perkins Centre University of SydneySydney NSW 2006Australia

The recent discovery of activator compounds binding to an allosteric site on the NAD+-dependent protein lysine deacetylase,sirtuin 6(SIRT6)has attracted interest and presents a pharmaceutical target for aging-related and cancer diseases.However,the mechanism underlying allosteric activation of SIRT6 by the activator MDL-801 remains largely elusive because no major conformational changes are observed upon activator binding.By combining molecular dynamics simulations with biochemical and kinetic analyses of wild-type SIRT6 and its variant M136 A,we show that conformational rotation of 2-methyl-4-fluoro-5-bromo substituent on the right phenyl ring(R-ring)of MDL-801,which uncovers previously unseen hydrophobic interactions,contributes to increased activating deacetylation activity of SIRT6.This hypothesis is further supported by the two newly synthesized MDL-801 derivatives through the removal of the 5-Br atom on the R-ring(MDL-801-D1)or the restraint of the rotation of the R-ring(MDL-801-D2).We further propose that the 5-Br atom serves as an allosteric driver that controls the ligand allosteric efficacy.Our study highlights the effect of allosteric enzyme catalytic activity by activator binding and provides a rational approach for enhancing deacetylation activity.

关键词： Allosteric driver Allosteric sites Allosteric mechanisms Drug design Enzyme catalysis Protein dynamics

Enzymatic Synthesis of a Diastereomer of Neoabyssomicin Derivative Using the Diels-Alderase AbyU

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Chinese Journal of Chemistry 2021年第7期39卷 1871-1877页

作者： Wenjuan Ding Changbiao Chi Xiaoyi Wei Changli Sun Jiajia Tu Ming Ma Qinglian Li Jianhua Ju CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology Guangdong Key Laboratory of Marine Materia MedicaRNAM Center for Marine MicrobiologySouth China Sea Institute of OceanologyChinese Academy of Sciences164 West Xingang RoadGuangzhouGuangdong510301 China College of Oceanology University of Chinese Academy of Sciences19 Yuquan RoadBeijing100049 China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) No.1119Haibin Rd.Nansha DistrictGuangzhouGuangdong510301 China State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing100191 China Key Laboratory of Plant Resources Conservation and Sustainable Utilization South China Botanical GardenChinese Academy of SciencesGuangzhouGuangdong510650 China

Main observation and conclusion The enzyme AbyU catalyses a Diels-Alder(DA)reaction during abyssomicin C biosynthesis.In this study,AbyU is shown to convert the native substrate of another Diels-Alderase(DAase),AbmU,t... 详细信息

关键词： Biosynthesis Bioorganic chemistry Enzyme catalysis Neoabyssomicin Diels-Alderase