1.Efficient biosynthesis of γ-aminobutyric acid by rationally engineering the catalytic pH range of a glutamate decarboxylase from Lactobacillus plantarum.
Jiewen XIAO ; Jin HAN ; Zhina QIAO ; Guodong ZHANG ; Wujun HUANG ; Kai QIAN ; Meijuan XU ; Xian ZHANG ; Taowei YANG ; Zhiming RAO
Chinese Journal of Biotechnology 2023;39(6):2108-2125
γ-aminobutyric acid can be produced by a one-step enzymatic reaction catalyzed by glutamic acid decarboxylase. The reaction system is simple and environmentally friendly. However, the majority of GAD enzymes catalyze the reaction under acidic pH at a relatively narrow range. Thus, inorganic salts are usually needed to maintain the optimal catalytic environment, which adds additional components to the reaction system. In addition, the pH of solution will gradually rise along with the production of γ-aminobutyric acid, which is not conducive for GAD to function continuously. In this study, we cloned the glutamate decarboxylase LpGAD from a Lactobacillus plantarum capable of efficiently producing γ-aminobutyric acid, and rationally engineered the catalytic pH range of LpGAD based on surface charge. A triple point mutant LpGADS24R/D88R/Y309K was obtained from different combinations of 9 point mutations. The enzyme activity at pH 6.0 was 1.68 times of that of the wild type, suggesting the catalytic pH range of the mutant was widened, and the possible mechanism underpinning this increase was discussed through kinetic simulation. Furthermore, we overexpressed the Lpgad and LpgadS24R/D88R/Y309K genes in Corynebacterium glutamicum E01 and optimized the transformation conditions. An optimized whole cell transformation process was conducted under 40 ℃, cell mass (OD600) 20, 100 g/L l-glutamic acid substrate and 100 μmol/L pyridoxal 5-phosphate. The γ-aminobutyric acid titer of the recombinant strain reached 402.8 g/L in a fed-batch reaction carried out in a 5 L fermenter without adjusting pH, which was 1.63 times higher than that of the control. This study expanded the catalytic pH range of and increased the enzyme activity of LpGAD. The improved production efficiency of γ-aminobutyric acid may facilitate its large-scale production.
Glutamate Decarboxylase/genetics*
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Lactobacillus plantarum/genetics*
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Catalysis
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gamma-Aminobutyric Acid
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Hydrogen-Ion Concentration
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Glutamic Acid
2.Small molecule inhibitors of RORγt for Th17 regulation in inflammatory and autoimmune diseases
Jiuping ZENG ; Mingxing LI ; Qianyun ZHAO ; Meijuan CHEN ; Long ZHAO ; Shulin WEI ; Huan YANG ; Yueshui ZHAO ; Anqi WANG ; Jing SHEN ; Fukuan DU ; Yu CHEN ; Shuai DENG ; Fang WANG ; Zhuo ZHANG ; Zhi LI ; Tiangang WANG ; Shengpeng WANG ; Zhangang XIAO ; Xu WU
Journal of Pharmaceutical Analysis 2023;13(6):545-562
As a ligand-dependent transcription factor,retinoid-associated orphan receptor γt(RORyt)that controls T helper(Th)17 cell differentiation and interleukin(IL)-17 expression plays a critical role in the pro-gression of several inflammatory and autoimmune conditions.An emerging novel approach to the therapy of these diseases thus involves controlling the transcriptional capacity of RORyt to decrease Th17 cell development and IL-17 production.Several RORyt inhibitors including both antagonists and inverse agonists have been discovered to regulate the transcriptional activity of RORyt by binding to orthosteric-or allosteric-binding sites in the ligand-binding domain.Some of small-molecule inhibitors have entered clinical evaluations.Therefore,in current review,the role of RORyt in Th17 regulation and Th17-related inflammatory and autoimmune diseases was highlighted.Notably,the recently developed RORyt inhibitors were summarized,with an emphasis on their optimization from lead compounds,ef-ficacy,toxicity,mechanisms of action,and clinical trials.The limitations of current development in this area were also discussed to facilitate future research.
3.Practice on the characteristic curriculum construction of undergraduate clinical medicine in Sino-foreign cooperative education program
Yi LI ; Xiao LIANG ; Chunming WANG ; Meijuan ZHU ; Li SHAO
Chinese Journal of Medical Education Research 2022;21(12):1626-1632
As one of the first institutions to carry out integrated education in China, the Shanghai Jiao Tong University School of Medicine has carried out a pilot reform of the organ system centered vertical single cycle integrated curriculum in the undergraduate medical education (five-year English stream) based on the Sino-foreign cooperative education program. The curriculum has been formed with multi-disciplinary single cycle integrated courses, longitudinal integrated courses, and three-dimensional specialized expansion electives. The curriculum focuses on the competency training of medical student. The aim is to highlight the teaching concept of early contact with clinic, attach importance to the cultivation and shaping of medical personality, achieve effective connection with post-graduation education, and realize the intersection and deep integration of social, humanities and medical professional courses through the construction of a series of course modules.
4. Investigation of potential pharmacodynamic substances and mechanism of Qingxin-zishen prescription decoction in treatment of menopause syndrome based on HPLC-Q-TOF-MS/MS and network pharmacology
Qian YAO ; Yun CHEN ; Wenzheng JU ; Jiandong ZOU ; Su LU ; Meijuan XU ; Qian YAO ; Juan SHANG ; Xiaoyun XI ; Ying CHEN ; Xiao GU
Chinese Journal of Clinical Pharmacology and Therapeutics 2022;27(5):481-497
AIM: To analyze the chemical ingredients of Qingxin-zishen prescription decoction (QZPD) and predict its main pharmacodynamic substances and mechanism in the prevention and treatment of menopause syndrome (MPS) with the help of high performance liquid chromatography-quadrupole-time of flight mass spectrometry (HPLC-Q-TOF/MS) combined with network pharmacology. METHODS: The chemical ingredients of QZPD were identified after analyzing the retention time, exact mass, secondary mass spectrometry fragmentation and other information obtained from HPLC-Q-TOF/MS and comparing them with the established chemical ingredients database and the literatures. The targets of ingredients in QZPD were predicted by Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) and SwissTargetPrediction database. The disease targets of MPS were obtained through Online Mendelian Inheritance in Man (OMIM) and GeneCards Database. Gene ontology (GO) function enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of potential targets were analyzed with the Metascape database. Cytoscape 3.7.2 software was used to construct the network of active components-key targets-pathways. AutoDockTools 4.2.5 software was applied in the molecular docking verification between the key active components and key targets. RESULTS: A total of 83 components were identified in QZPD and 847 drug targets were predicted. After intersection them with 3 050 disease targets, 395 common targets were obtained. After network topology analysis, 74 key targets were obtained, involving mitogen-activated protein kinase (MAPK), phosphatidylinositol-3 kinase/protein kinase B (PI3K/Akt), transforming growth factor-β (TGF-β) and other signaling pathways. Molecular docking analysis results indicated that 23 key active components, such as berberine, epiberberine, coptisine, geissoschizine methyl ether, liensinine, norcoclaurine, palmatine, quercetin, and luteolin, had good binding activity with several of the key targets. CONCLUSION: This study preliminarily identifies the potential effective chemical ingredients of QZPD, predicts its targets in the prevention and treatment of MPS, which provides supporting information for the further study of the pharmacodynamic substances and mechanisms of QZPD.
5.Conditional reprogramming: next generation cell culture.
Xiaoxiao WU ; Shengpeng WANG ; Mingxing LI ; Jing LI ; Jing SHEN ; Yueshui ZHAO ; Jun PANG ; Qinglian WEN ; Meijuan CHEN ; Bin WEI ; Parham Jabbarzadeh KABOLI ; Fukuan DU ; Qijie ZHAO ; Chi Hin CHO ; Yitao WANG ; Zhangang XIAO ; Xu WU
Acta Pharmaceutica Sinica B 2020;10(8):1360-1381
Long-term primary culture of mammalian cells has been always difficult due to unavoidable senescence. Conventional methods for generating immortalized cell lines usually require manipulation of genome which leads to change of important biological and genetic characteristics. Recently, conditional reprogramming (CR) emerges as a novel next generation tool for long-term culture of primary epithelium cells derived from almost all origins without alteration of genetic background of primary cells. CR co-cultures primary cells with inactivated mouse 3T3-J2 fibroblasts in the presence of RHO-related protein kinase (ROCK) inhibitor Y-27632, enabling primary cells to acquire stem-like characteristics while retain their ability to fully differentiate. With only a few years' development, CR shows broad prospects in applications in varied areas including disease modeling, regenerative medicine, drug evaluation, drug discovery as well as precision medicine. This review is thus to comprehensively summarize and assess current progress in understanding mechanism of CR and its wide applications, highlighting the value of CR in both basic and translational researches and discussing the challenges faced with CR.
6.The understanding of Epstein-Barr virus associated lymphoproliferative disorder
Xiaoge ZHOU ; Yanlin ZHANG ; Jianlan XIE ; Yuhua HUANG ; Yuanyuan ZHENG ; Wensheng LI ; Hao CHEN ; Fang LIU ; Huaxiong PAN ; Ping WEI ; Zhe WANG ; Yuchang HU ; Kaiyan YANG ; Hualiang XIAO ; Meijuan WU ; Weihua YIN ; Kaiyong MEI ; Gang CHEN ; Xiaochu YAN ; Gang MENG ; Gang XU ; Juan LI ; Sufang TIAN ; Jun ZHU ; Yuqin SONG ; Weijing ZHANG
Chinese Journal of Pathology 2016;45(12):817-821
In recent years , there are increasing articles concerning Epstein-Barr virus associated lymphoproliferative disorder (EBV+LPD), and the name of EBV +LPD is used widely.However,the meaning of EBV+LPD used is not the same , which triggered confusion of the understanding and obstacles of the communication.In order to solve this problem.Literature was reviewed with combination of our cases to clarify the concept of EBV +LPD and to expound our understanding about it .In general, it is currently accepted that EBV +LPD refers to a spectrum of lymphoid tissue diseases with EBV infection , including hyperplasia , borderline lesions , and neoplastic diseases .According to this concept , EBV+LPD should not include infectious mononucleosis ( IM ) and severe acute EBV infection ( EBV +hemophagocytic lymphohistiocytosis, fatal IM, fulminant IM, fulminant T-cell LPD), and should not include the explicitly named EBV+lymphomas ( such as extranodal NK/T cell lymphoma , aggressive NK cell leukemia , Burkitt lymphoma, and Hodgkin lymphoma , etc.) either.EBV +LPD should currently include: ( 1 ) EBV +B cell-LPD:lymphomatoid granulomatosis , EBV +immunodeficiency related LPD , chronic active EBV infection-B cell type, senile EBV +LPD, etc.(2) EBV +T/NK cell-LPD:CAEBV-T/NK cell type, hydroa vacciniforme, hypersensitivity of mosquito bite, etc.In addition, EBV+LPD is classified, based on the disease process , pathological and molecular data , as 3 grades:grade1, hyperplasia ( polymorphic lesions with polyclonal cells ); grade 2, borderline ( polymorphic lesions with clonality ); grade 3, neoplasm (monomorphic lesions with clonality).There are overlaps between EBV +LPD and typical hyperplasia, as well as EBV+LPD and typical lymphomas .However , the most important tasks are clinical vigilance , early identification of potential severe complications , and treating the patients in a timely manner to avoid serious complications , as well as the active treatment to save lives when the complications happened .
7.Construction and identification of pcDNA3-HBsAg-p30-ROP2 expression vec-tor
Qingkuan WEI ; Yingting WANG ; Yunqin YAN ; Ting XIAO ; Jin LI ; Chao XU ; Gongzhen LIU ; Meijuan LIU ; Weixia ZHONG ; Kun YIN ; Bin FU ; Ge YAN ; Bingcheng HUANG
Chinese Journal of Schistosomiasis Control 2014;(1):46-50
Objective To construct a multi-gene recombinant pcDNA3-HBsAg-p30-ROP2 expression vector and identify it preliminarily. Methods According to recombinant pcDNA3-p30-ROP2 restriction sites,HBV HBsAg gene sequences of primers were designed and synthesized to amplify target fragment,and then cloned into pcDNA3-HbsAg-p30-ROP2 expression vector. Af-ter sequencing,it was identified finally by restriction enzyme digestion and other molecular biology techniques. Results HBV HBsAg gene segment was amplified by PCR and the multi-gene recombinant pcDNA3-HBsAg-p30-ROP2 expression vector was constructed and identified to be correct as theoretical values. The PCR and restriction enzyme digestion results showed that HBsAg and p30-ROP2 gene in recombinant plasmid were confirmed by DNA sequencing. Conclusion The multi-gene recombinant pcD-NA3-HBsAg-p30-ROP2 expression vector is successfully constructed.
8.Incidence and risk factors of spontaneous hemorrhagic transformation in cardioembolism and large artery atherosclerotic infarction
Meijuan XIAO ; Weiyong YIN ; Zusen YE ; Yungang CAO ; Bei SHAO ; Zhao HAN
Chinese Journal of General Practitioners 2014;13(10):848-850
To explore the incidence and risk factors for spontaneous hemorrhagic transformation (HT) of cardioembolism (CE,n =150) and large artery atherosclerotic infarction (LAA,n =370).The incidence of HT was 29.3% in CE.And it was significantly higher than 9.7% (P <0.05).Infarct size,low-density lipoprotein-cholesterol (LDL-C) and admission National Institutes of Health Stroke Scale (NIHSS) score were independent predictors of spontaneous hemorrhagic transformation in LAA.OR values were 3.92,2.96 and 1.45 respectively.Infarct size,admission NIHSS score and random blood glucose level were independent predictors of spontaneous hemorrhagic transformation in CE.OR values were 4.86,2.42 and 1.42 respectively.As compared with LAA,CE was more prone to HT.LAA and CE-related factors of hemorrhagic transformation are not completely identical.
9.Report of one patient of cerebral infarction associated with methamphetamine and a review of pertinent literature
Meijuan XIAO ; Hai ZOU ; Weiyong YIN
Chinese Journal of General Practitioners 2014;(6):492-494
A case of methamphetamine-related cerebral infarction was reported and the relevant databases of CBMdisc and Medline were searched.Among 14 cases of ischemic stroke , the ratio of male:female was 9∶5 and the age range 19-45 years.There were anterior circulation lesions ( n=13,92.8%) and 10 of them (71.3%) had cerebral vascular occlusion or stenosis.And the predominant manifestation was hemiplegia (85.7%);among 34 cases of hemorrhagic stroke ,the ratio of male: female was 12∶5 and the age range 16-60 years.And 28 cases (82%) were≤45 years.Cerebral hemorrhage was the most common (85%).The major manifestations were headache ( n =26, 76%) and disturbance of consciousness (n=21,62%).The methamphetamine-related stroke occurs frequently in young males.And ischemic stroke tends to involve anterior circulation and cause hemiplegia.Yet hemorrhagic stroke has extensive attack sites and headache and disturbance of consciousness are quite common.
10.Causes of diarrheas from kidney transplantation from donation after cardiac death and nursing strategy
Meijuan WU ; Yuan LIAO ; Jing XIAO ; Fei WANG ; Haiqing JIANG ; Xinxin∥ ZHAO
Modern Clinical Nursing 2013;(10):42-44
Objective To study the diarrhea causes and nursing care after kidney transplantation from donation after cardiac death(DCD).Methods The clinical data of 91 patients undergoing kidney transplantations from DCD were retrospectively analyzed from November 2011 to May 2013 in our department,to investigate the incidence of diarrhea and the causes.Results Eighty three cases contracted diarrhea in 91 recipients,with the incidence of diarrhea 91.2%.The use of immunosuppressive agents,intestinal flora,infection and bowel movement dysfunction were all related to the diarrhea.Conclusions The incidence of diarrhea is high and the causes are complex after kidney transplantation from DCD.So nurses should take the appropriate care measures to improve the quality of nursing,avoiding complications and ensuring transplant results based on a different cause of diarrhea.

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