Hongbo Ye, Qingye Li, Xiaoling Tang, Renchao Zheng
{"title":"[Transaminases: high-throughput screening <i>via</i> a ketone-fluorescent probe and applications].","authors":"Hongbo Ye, Qingye Li, Xiaoling Tang, Renchao Zheng","doi":"10.13345/j.cjb.240216","DOIUrl":"https://doi.org/10.13345/j.cjb.240216","url":null,"abstract":"<p><p>Transaminases are a class of enzymes that catalyze the transfer of amino between amino acids and keto acids, playing an important role in the biosynthesis of organic amines and the corresponding derivatives. However, natural enzymes often have low catalytic efficiency against non-natural substrates, which limits their widespread applications. Enzyme engineering serves as an effective approach to improve the catalytic properties and thereby expand the application scope of transaminases. In this study, a high-throughput screening method for transaminases was established based on the fluorescent color reaction between methoxy-2-aminobenzoxime (PMA) and ketones. According to the changes in fluorescence intensity, the concentration changes of ketones could be easily monitored. The efficiency, sensitivity, and accuracy of the screening method were improved by optimization of the system. With 4-hydroxy-2-butanone as the substrate, the mutant library of the transaminase from <i>Actinobacteria</i> sp. was established and a mutant with increased activity was successfully obtained, which improved the production efficiency of (<i>R</i>)-3-aminobutanol by enzyme-catalyzed synthesis. This study laid an important foundation for efficient screening, modification, and application of transaminase.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"41 1","pages":"416-426"},"PeriodicalIF":0.0,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143041413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dongyang Kong, Lu Wang, Hong Zhang, Jingchao Zhang
{"title":"[Visualization of flagella and its applications in research on flagellar functions].","authors":"Dongyang Kong, Lu Wang, Hong Zhang, Jingchao Zhang","doi":"10.13345/j.cjb.240227","DOIUrl":"https://doi.org/10.13345/j.cjb.240227","url":null,"abstract":"<p><p>Flagella are important protein structures on the cell surface of bacteria and the main appendage for bacterial swimming. Flagella play a crucial role in bacterial motility, chemotaxis, pathogenicity, and environmental sensing. With the development of microscopic tracking technology and flagellum visualization tools, new forms of flagellar motility and increasing roles of flagella in the physiological activities of bacteria have been discovered. This review introduces the visualization methods of flagella and the applications of these methods in studying flagellar functions, giving insights into exploring the functions of flagella and laying a theoretical foundation for its future applications in inhibiting bacterial transmission and treating bacterial infections.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"41 1","pages":"117-130"},"PeriodicalIF":0.0,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143041533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Research progress in anti-enzymatic antimicrobial peptides].","authors":"Changxuan Shao, Mengcheng Wang, Yuanmengxue Wang, Shiqi He, Yongjie Zhu, Anshan Shan","doi":"10.13345/j.cjb.240077","DOIUrl":"https://doi.org/10.13345/j.cjb.240077","url":null,"abstract":"<p><p>Antimicrobial peptides (AMPs) are small molecular peptides widely existing in the innate immunity of organisms, serving as the first line of defense. Natural AMPs possess various biological activities and are difficult to develop drug resistance. However, they are easily broken down by digestive enzymes in the body. In recent years, increasing methods have been reported to enhance the stability of AMPs, including incorporation of unnatural amino acids, chemical modifications, strategic avoidance of enzyme cleavage sites, cyclization, and nano peptide design. This review summarizes the methods for improving the stability of AMPs against protease degradation, aiming to provide references for further research in this field.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"40 12","pages":"4396-4407"},"PeriodicalIF":0.0,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142897279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Junli Cheng, Junrong Yan, Shuning Hou, Zhiwei Zhu, Pengfei Li
{"title":"[Screening and identification of key miRNAs in post-transcriptional regulation of CART in the bovine hypothalamus].","authors":"Junli Cheng, Junrong Yan, Shuning Hou, Zhiwei Zhu, Pengfei Li","doi":"10.13345/j.cjb.240296","DOIUrl":"https://doi.org/10.13345/j.cjb.240296","url":null,"abstract":"<p><p>This study aimed to explore the roles of microRNAs (miRNAs) in the post-transcriptional regulation of cocaine- and amphetamine-regulated transcript (CART) peptide in the bovine hypothalamus and to screen key regulatory miRNAs. Targetscan was used to predict the potential miRNAs binding to <i>CART</i> 3' untranslated regions (3'UTR). Bioinformatics analysis predicted 7 miRNA binding sites in the bovine <i>CART</i> 3'UTR, which were bta-miR-377, bta-miR-331-3p, bta-miR-491, bta-miR-493, bta-miR-758, bta-miR-877, and bta-miR-381, respectively. Reverse transcription-PCR (RT-PCR) was carried out to determine the endogenous expression of <i>CART</i> and target miRNAs in the bovine hypothalamus. All the 7 target miRNAs and <i>CART</i> were endogenously expressed in the bovine hypothalamus. The dual-luciferase reporter gene assay was employed to detect the targeted binding relationship between <i>CART</i> 3'UTR and target miRNAs obtained from bioinformatics analysis. The dual-luciferase reporter gene assay confirmed that the 3'UTR of <i>CART</i> had a targeted binding relationship with the 7 target miRNAs. Cell experiments were conducted to examine the effects of target miRNAs on the messenger RNA (mRNA) and protein levels of exogenous CART and screen for key regulatory miRNAs. The results of cell experiments showed that the 7 miRNAs downregulated the mRNA level of <i>CART</i>, with bta-miR-491 demonstrating the strongest downregulating effect. Bta-miR-377, bta-miR-331-3p, bta-miR-491, bta-miR-493, and bta-miR-381 downregulated the protein level of CART, with bta-miR-381 exerting the strongest downregulating effect. Animal experiments were conducted to explore the effects of key regulatory miRNAs on the mRNA and protein levels of CART in the hypothalamus and the CART concentration in the serum. The results from animal experiments showed that miR-491 and miR-381 regulated the endogenous expression of CART in the hypothalamus and the concentration in the serum by binding to the <i>CART</i> 3'UTR. These results suggest that miR-491 and miR-381 are the main miRNAs regulating CART expression in the bovine hypothalamus, which can affect serum CART concentration by modulating endogenous CART expression.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"40 12","pages":"4557-4572"},"PeriodicalIF":0.0,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142897349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jinlei Sun, Ruiming Yu, Liping Zhang, Zhongwang Zhang, Yonglu Wang, Li Pan, Quanwei Zhang, Xinsheng Liu
{"title":"[Screening and identification of host proteins interacting with the non-structural protein 15 (Nsp15) of porcine epidemic diarrhea virus].","authors":"Jinlei Sun, Ruiming Yu, Liping Zhang, Zhongwang Zhang, Yonglu Wang, Li Pan, Quanwei Zhang, Xinsheng Liu","doi":"10.13345/j.cjb.240083","DOIUrl":"https://doi.org/10.13345/j.cjb.240083","url":null,"abstract":"<p><p>To screen and identify the key host proteins interacting with the non-structural protein 15 (Nsp15) of porcine epidemic diarrhea virus (PEDV). The IP/pull-down assay and mass spectrometry were employed to screen and identify the host proteins interacting with Nsp15. The interaction between the host protein and Nsp15 was studied by co-immunoprecipitation and laser scanning confocal microscopy. Finally, Western blotting and RT-qPCR were employed to examine the interaction between SLC25a3 and PEDV. The recombinant eukaryotic expression vector pcDNA3.1(+)-Flag-Nsp15 was successfully constructed, and the host protein SLC25a3 interacting with PEDV Nsp15 was screened out. An interaction existed between SLC25a3 and Nsp15, and SLC25a3 significantly inhibited PEDV replication in a dose-dependent manner. SLC25a3 inhibits PEDV replication. The results of this study provide a basis for deciphering the role and mechanism of SLC25a3 in the host immune response to PEDV infection.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"40 12","pages":"4533-4545"},"PeriodicalIF":0.0,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142897344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Advances in the anti-host interferon immune response of bluetongue virus].","authors":"Qisha Li, Xuyan Cai, Shimei Luo, Yunyi Chen, Huashan Yi, Xianping Ma","doi":"10.13345/j.cjb.240080","DOIUrl":"https://doi.org/10.13345/j.cjb.240080","url":null,"abstract":"<p><p>Bluetongue virus (BTV) usually infects sheep, cattle, deer and other domesticated and wild ruminants through the bite of the vector insects, <i>Culicoide</i>, causing bluetongue (BT). BT in subtropical and even temperate regions poses a serious threat to the development and international trade of the livestock industry. This article introduced the structure and cellular invasion, and summarized the mechanisms of anti-BTV immune response of host cells and antagonism of host cell innate immune response by the non-structural proteins (e.g., NS3 and NS4) and structural proteins (e.g., VP3 and VP4) of BTV. This review provided a basis for understanding the antagonism mechanisms of BTV against the interferon (IFN) immune response in the host cell and the pathogenesis of BTV as well as for developing novel vaccines against this virus.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"40 12","pages":"4439-4451"},"PeriodicalIF":0.0,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142897063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zening Wang, Mingfeng Jiang, Jiu Qu, Xiaowei Li, Yili Liu
{"title":"[Construction of a muscle-specific synthetic promoter library and correlation analysis of the element composition and activity of highly active promoters].","authors":"Zening Wang, Mingfeng Jiang, Jiu Qu, Xiaowei Li, Yili Liu","doi":"10.13345/j.cjb.240432","DOIUrl":"https://doi.org/10.13345/j.cjb.240432","url":null,"abstract":"<p><p>The purpose of this study is to construct a muscle-specific synthetic promoter library, screen out muscle-specific promoters with high activity, analyze the relationship between element composition and activity of highly active promoters, and provide a theoretical basis for artificial synthesis of promoters. In this study, 19 promoter fragments derived from muscle-specific elements, conserved elements, and viral regulatory sequences were selected and randomLy connected to construct a muscle-specific synthetic promoter library. The luciferase plasmids pCMV-Luc and pSPs-Luc were constructed and transfected into the myoblast cell line C2C12. The activities of the synthesized promoters were evaluated by the luciferase activity assay. Two non-muscle-derived cell lines HeLa and 3T3 were used to verify the muscle specificity of the highly active promoters. The sequences of promoters with high activity, good muscle specificity, and correct sequences were analyzed to explore the relationship between the element composition and activity of promoters. We successfully constructed a muscle-specific promoter library and screened out 321 effective synthetic promoter plasmids. Among them, the activity of SP-301 promoter was 5.63 times that of CMV. The 15 promoters with high activity were muscle-specific. In the promoters with high activity and correct sequences, there was a relationship between their element composition and activity. Muscle-specific elements accounted for a high proportion in the promoters, while they had weak correlations with the promoter activity, being tissue-specific determinants. Viral elements accounted for no less than 20% in highly active promoters, which may be the key elements for the promoter activity. The content of conserved elements was proportional to the promoter activity. This study lays a theoretical foundation for the synthesis of tissue-specific efficient promoters and provides a new idea for the construction and application of <i>in</i>-<i>situ</i> gene delivery systems.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"40 12","pages":"4616-4627"},"PeriodicalIF":0.0,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142897068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"[Porcine reproductive and respiratory syndrome virus infection induces glycolysis of macrophages to facilitate viral replication].","authors":"Dianning Duan, Yanan Li, Yanjiao Liang, Shiting Huang, Jiankui Liu, Longxin Qiu, Hongbo Chen","doi":"10.13345/j.cjb.240275","DOIUrl":"https://doi.org/10.13345/j.cjb.240275","url":null,"abstract":"<p><p>This work aims to explore the effect of glycolysis on the replication of porcine reproductive and respiratory syndrome virus (PRRSV) in porcine alveolar macrophages (PAMs). The changes of glucose metabolism, PRRSV protein levels, PRRSV titers, and the relative expression levels of genes and proteins in PAMs were analyzed by ELISA, qPCR, virus titration, and Western blotting after PRRSV infection. The effect of hypoxia-inducible factor-1α (HIF-1α) on PRRSV replication was subsequently assessed by specific siRNAs targeting to HIF-1α. The results showed that PRRSV infection enhanced glycolysis, elevated the levels of glucose uptake and lactate in the supernatant (<i>P</i><0.05 and 0.01, respectively), reduced ATP production (<i>P</i><0.05), and up-regulated the expression of hexokinase 2 (HK2), 6-phosphofructo-2-kinase/fructose-2, 6-biphosphatase 3 (PFKFB3), and pyruvate kinase isozyme type M2 (PKM2) in PAMs (<i>P</i><0.05 and 0.01, respectively). Glycolysis inhibitors down-regulated the expression of PRRSV proteins and reduced virus titers (<i>P</i><0.01). The knockdown of HIF-1α by siRNAs inhibited glycolysis and lowered PRRSV titers (<i>P</i><0.05). In addition, the interferon pathways inhibited by PRRSV infection were reversed by the inhibition of glycolysis. These findings may facilitate further investigation of the role of glycolysis in PRRSV replication.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"40 12","pages":"4546-4556"},"PeriodicalIF":0.0,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142897248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lihan Tao, Chengcheng Wu, Cui Lin, Zhaofeng Kang, Jianzhen Huang
{"title":"[Prokaryotic expression and helicase activity analysis of PDCoV NSP13].","authors":"Lihan Tao, Chengcheng Wu, Cui Lin, Zhaofeng Kang, Jianzhen Huang","doi":"10.13345/j.cjb.240039","DOIUrl":"https://doi.org/10.13345/j.cjb.240039","url":null,"abstract":"<p><p>Porcine deltacoronavirus (PDCoV) is a major pathogen causing fatal diarrhea in suckling piglets, and there is currently a lack of effective vaccines and drugs to prevent and control the virus. The nonstructural protein 13 (NSP13) serves as a virus-coded helicase and is considered to be a crucial target for antiviral drugs, making it imperative to investigate the helicase activity of NSP13. In this study, the <i>NSP13</i> gene of PDCoV was synthesized and integrated into the prokaryotic expression vector pET-28a to construct the recombinant plasmid pET-28a-NSP13. NSP13 was successfully expressed in BL21 (DE3) and subsequently purified. The study also verified the helicase activity of the purified NSP13 and explored the factors that influence this activity. The results indicated that NSP13 from PDCoV was effectively expressed in the prokaryotic system and exhibited helicase activity, capable of unwinding double-stranded DNA with a tail at the 5' end. Additionally, NSP13 demonstrated an annealing function by promoting the complementary pairing of single-stranded nucleotide chains to form double strands. The helicase activity of NSP13 was affected by metal ions, but Mg<sup>2+</sup>concentrations in the range of 0.5-6.0 mmol/L had no significant effect on helicase activity of NSP13. When the solution pH was in the range of 4-9, there was no difference in helicase activity. ATP concentrations in the range of 0.25-6.00 mmol/L had a weak effect on helicase activity, and NSP13 concentration ≥80 nmol/L inhibited the helicase activity. We obtained the NSP13 of PDCoV and investigated its helicase activity. These findings provided a theoretical foundation for the further research on the regulatory mechanism of NSP13 in PDCoV replication and the development of anti-coronaviral drugs.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"40 12","pages":"4573-4585"},"PeriodicalIF":0.0,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142897270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rong Huang, Hejian Zhang, Min Wu, Zhiyue Men, Huanyu Chu, Jie Bai, Hong Chang, Jian Cheng, Xiaoping Liao, Yuwan Liu, Yajian Song, Huifeng Jiang
{"title":"[AcidBasePred: a protein acid-base tolerance prediction platform based on deep learning].","authors":"Rong Huang, Hejian Zhang, Min Wu, Zhiyue Men, Huanyu Chu, Jie Bai, Hong Chang, Jian Cheng, Xiaoping Liao, Yuwan Liu, Yajian Song, Huifeng Jiang","doi":"10.13345/j.cjb.240255","DOIUrl":"https://doi.org/10.13345/j.cjb.240255","url":null,"abstract":"<p><p>The structures and activities of enzymes are influenced by pH of the environment. Understanding and distinguishing the adaptation mechanisms of enzymes to extreme pH values is of great significance for elucidating the molecular mechanisms and promoting the industrial applications of enzymes. In this study, the ESM-2 protein language model was used to encode the secreted microbial proteins with the optimal performance above pH 9 and below pH 5, which yielded 47 725 high-pH protein sequences and 66 079 low-pH protein sequences, respectively. A deep learning model was constructed to identify protein acid-base tolerance based on amino acid sequences. The model showcased significantly higher accuracy than other methods, with the overall accuracy of 94.8%, precision of 91.8%, and a recall rate of 93.4% on the test set. Furthermore, we built a website (https://enzymepred.biodesign.ac.cn), which enabled users to predict the acid-base tolerance by submitting the protein sequences of enzymes. This study has accelerated the application of enzymes in various fields, including biotechnology, pharmaceuticals, and chemicals. It provides a powerful tool for the rapid screening and optimization of industrial enzymes.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"40 12","pages":"4670-4681"},"PeriodicalIF":0.0,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142897135","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}