{"title":"微生物转谷氨酰胺酶酶原的前肽工程:实现生物连接应用中的底物依赖性活化。","authors":"Ryutaro Ariyoshi, Takashi Matsuzaki, Ryo Sato, Kosuke Minamihata, Kounosuke Hayashi, Taisei Koga, Kensei Orita, Riko Nishioka, Rie Wakabayashi, Masahiro Goto and Noriho Kamiya*, ","doi":"10.1021/acs.bioconjchem.3c00544","DOIUrl":null,"url":null,"abstract":"<p >Microbial transglutaminase (MTG) from <i>Streptomyces mobaraensis</i> is a powerful biocatalytic glue for site-specific cross-linking of a range of biomolecules and synthetic molecules that have an MTG-reactive moiety. The preparation of active recombinant MTG requires post-translational proteolytic digestion of a propeptide that functions as an intramolecular chaperone to assist the correct folding of the MTG zymogen (MTGz) in the biosynthesis. Herein, we report <u>e</u>ngineered active <u>z</u>ymogen of MTG (EzMTG) that is expressed in soluble form in the host <i>Escherichia coli</i> cytosol and exhibits cross-linking activity without limited proteolysis of the propeptide. We found that the saturation mutagenesis of residues K10 or Y12 in the propeptide domain generated several active MTGz mutants. In particular, the K10D/Y12G mutant exhibited catalytic activity comparable to that of mature MTG. However, the expression level was low, possibly because of decreased chaperone activity and/or the promiscuous substrate specificity of MTG, which is potentially harmful to the host cells. The K10R/Y12A mutant exhibited specific substrate-dependent reactivity toward peptidyl substrates. Quantitative analysis of the binding affinity of the mutated propeptides to the active site of MTG suggested an inverse relationship between the binding affinity and the catalytic activity of EzMTG. Our proof-of-concept study provides insights into the design of a new biocatalyst using the MTGz as a scaffold and a potential route to high-throughput screening of EzMTG mutants for bioconjugation applications.</p>","PeriodicalId":29,"journal":{"name":"Bioconjugate Chemistry Bioconjugate","volume":null,"pages":null},"PeriodicalIF":4.0000,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Engineering the Propeptide of Microbial Transglutaminase Zymogen: Enabling Substrate-Dependent Activation for Bioconjugation Applications\",\"authors\":\"Ryutaro Ariyoshi, Takashi Matsuzaki, Ryo Sato, Kosuke Minamihata, Kounosuke Hayashi, Taisei Koga, Kensei Orita, Riko Nishioka, Rie Wakabayashi, Masahiro Goto and Noriho Kamiya*, \",\"doi\":\"10.1021/acs.bioconjchem.3c00544\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p >Microbial transglutaminase (MTG) from <i>Streptomyces mobaraensis</i> is a powerful biocatalytic glue for site-specific cross-linking of a range of biomolecules and synthetic molecules that have an MTG-reactive moiety. The preparation of active recombinant MTG requires post-translational proteolytic digestion of a propeptide that functions as an intramolecular chaperone to assist the correct folding of the MTG zymogen (MTGz) in the biosynthesis. Herein, we report <u>e</u>ngineered active <u>z</u>ymogen of MTG (EzMTG) that is expressed in soluble form in the host <i>Escherichia coli</i> cytosol and exhibits cross-linking activity without limited proteolysis of the propeptide. We found that the saturation mutagenesis of residues K10 or Y12 in the propeptide domain generated several active MTGz mutants. In particular, the K10D/Y12G mutant exhibited catalytic activity comparable to that of mature MTG. However, the expression level was low, possibly because of decreased chaperone activity and/or the promiscuous substrate specificity of MTG, which is potentially harmful to the host cells. The K10R/Y12A mutant exhibited specific substrate-dependent reactivity toward peptidyl substrates. Quantitative analysis of the binding affinity of the mutated propeptides to the active site of MTG suggested an inverse relationship between the binding affinity and the catalytic activity of EzMTG. Our proof-of-concept study provides insights into the design of a new biocatalyst using the MTGz as a scaffold and a potential route to high-throughput screening of EzMTG mutants for bioconjugation applications.</p>\",\"PeriodicalId\":29,\"journal\":{\"name\":\"Bioconjugate Chemistry Bioconjugate\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":4.0000,\"publicationDate\":\"2024-02-29\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Bioconjugate Chemistry Bioconjugate\",\"FirstCategoryId\":\"1\",\"ListUrlMain\":\"https://pubs.acs.org/doi/10.1021/acs.bioconjchem.3c00544\",\"RegionNum\":2,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"BIOCHEMICAL RESEARCH METHODS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Bioconjugate Chemistry Bioconjugate","FirstCategoryId":"1","ListUrlMain":"https://pubs.acs.org/doi/10.1021/acs.bioconjchem.3c00544","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"BIOCHEMICAL RESEARCH METHODS","Score":null,"Total":0}
Engineering the Propeptide of Microbial Transglutaminase Zymogen: Enabling Substrate-Dependent Activation for Bioconjugation Applications
Microbial transglutaminase (MTG) from Streptomyces mobaraensis is a powerful biocatalytic glue for site-specific cross-linking of a range of biomolecules and synthetic molecules that have an MTG-reactive moiety. The preparation of active recombinant MTG requires post-translational proteolytic digestion of a propeptide that functions as an intramolecular chaperone to assist the correct folding of the MTG zymogen (MTGz) in the biosynthesis. Herein, we report engineered active zymogen of MTG (EzMTG) that is expressed in soluble form in the host Escherichia coli cytosol and exhibits cross-linking activity without limited proteolysis of the propeptide. We found that the saturation mutagenesis of residues K10 or Y12 in the propeptide domain generated several active MTGz mutants. In particular, the K10D/Y12G mutant exhibited catalytic activity comparable to that of mature MTG. However, the expression level was low, possibly because of decreased chaperone activity and/or the promiscuous substrate specificity of MTG, which is potentially harmful to the host cells. The K10R/Y12A mutant exhibited specific substrate-dependent reactivity toward peptidyl substrates. Quantitative analysis of the binding affinity of the mutated propeptides to the active site of MTG suggested an inverse relationship between the binding affinity and the catalytic activity of EzMTG. Our proof-of-concept study provides insights into the design of a new biocatalyst using the MTGz as a scaffold and a potential route to high-throughput screening of EzMTG mutants for bioconjugation applications.
期刊介绍:
Bioconjugate Chemistry invites original contributions on all research at the interface between man-made and biological materials. The mission of the journal is to communicate to advances in fields including therapeutic delivery, imaging, bionanotechnology, and synthetic biology. Bioconjugate Chemistry is intended to provide a forum for presentation of research relevant to all aspects of bioconjugates, including the preparation, properties and applications of biomolecular conjugates.