{"title":"RecBCD enzyme: mechanistic insights from mutants of a complex helicase-nuclease.","authors":"Susan K Amundsen, Gerald R Smith","doi":"10.1128/mmbr.00041-23","DOIUrl":null,"url":null,"abstract":"<p><p>SUMMARYRecBCD enzyme is a multi-functional protein that initiates the major pathway of homologous genetic recombination and DNA double-strand break repair in <i>Escherichia coli</i>. It is also required for high cell viability and aids proper DNA replication. This 330-kDa, three-subunit enzyme is one of the fastest, most processive helicases known and contains a potent nuclease controlled by Chi sites, hotspots of recombination, in DNA. RecBCD undergoes major changes in activity and conformation when, during DNA unwinding, it encounters Chi (5'-GCTGGTGG-3') and nicks DNA nearby. Here, we discuss the multitude of mutations in each subunit that affect one or another activity of RecBCD and its control by Chi. These mutants have given deep insights into how the multiple activities of this complex enzyme are coordinated and how it acts in living cells. Similar studies could help reveal how other complex enzymes are controlled by inter-subunit interactions and conformational changes.</p>","PeriodicalId":18520,"journal":{"name":"Microbiology and Molecular Biology Reviews","volume":" ","pages":"e0004123"},"PeriodicalIF":8.0000,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10732027/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Microbiology and Molecular Biology Reviews","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1128/mmbr.00041-23","RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2023/12/4 0:00:00","PubModel":"Epub","JCR":"Q1","JCRName":"MICROBIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
SUMMARYRecBCD enzyme is a multi-functional protein that initiates the major pathway of homologous genetic recombination and DNA double-strand break repair in Escherichia coli. It is also required for high cell viability and aids proper DNA replication. This 330-kDa, three-subunit enzyme is one of the fastest, most processive helicases known and contains a potent nuclease controlled by Chi sites, hotspots of recombination, in DNA. RecBCD undergoes major changes in activity and conformation when, during DNA unwinding, it encounters Chi (5'-GCTGGTGG-3') and nicks DNA nearby. Here, we discuss the multitude of mutations in each subunit that affect one or another activity of RecBCD and its control by Chi. These mutants have given deep insights into how the multiple activities of this complex enzyme are coordinated and how it acts in living cells. Similar studies could help reveal how other complex enzymes are controlled by inter-subunit interactions and conformational changes.
期刊介绍:
Microbiology and Molecular Biology Reviews (MMBR), a journal that explores the significance and interrelationships of recent discoveries in various microbiology fields, publishes review articles that help both specialists and nonspecialists understand and apply the latest findings in their own research. MMBR covers a wide range of topics in microbiology, including microbial ecology, evolution, parasitology, biotechnology, and immunology. The journal caters to scientists with diverse interests in all areas of microbial science and encompasses viruses, bacteria, archaea, fungi, unicellular eukaryotes, and microbial parasites. MMBR primarily publishes authoritative and critical reviews that push the boundaries of knowledge, appealing to both specialists and generalists. The journal often includes descriptive figures and tables to enhance understanding. Indexed/Abstracted in various databases such as Agricola, BIOSIS Previews, CAB Abstracts, Cambridge Scientific Abstracts, Chemical Abstracts Service, Current Contents- Life Sciences, EMBASE, Food Science and Technology Abstracts, Illustrata, MEDLINE, Science Citation Index Expanded (Web of Science), Summon, and Scopus, among others.