M Pilar Garcillán-Barcia, Radoslaw Pluta, Fabián Lorenzo-Díaz, Alicia Bravo, Manuel Espinosa
{"title":"The Facts and Family Secrets of Plasmids That Replicate via the Rolling-Circle Mechanism.","authors":"M Pilar Garcillán-Barcia, Radoslaw Pluta, Fabián Lorenzo-Díaz, Alicia Bravo, Manuel Espinosa","doi":"10.1128/MMBR.00222-20","DOIUrl":null,"url":null,"abstract":"<p><p>Plasmids are self-replicative DNA elements that are transferred between bacteria. Plasmids encode not only antibiotic resistance genes but also adaptive genes that allow their hosts to colonize new niches. Plasmid transfer is achieved by conjugation (or mobilization), phage-mediated transduction, and natural transformation. Thousands of plasmids use the rolling-circle mechanism for their propagation (RCR plasmids). They are ubiquitous, have a high copy number, exhibit a broad host range, and often can be mobilized among bacterial species. Based upon the replicon, RCR plasmids have been grouped into several families, the best known of them being pC194 and pUB110 (Rep_1 family), pMV158 and pE194 (Rep_2 family), and pT181 and pC221 (Rep_trans family). Genetic traits of RCR plasmids are analyzed concerning (i) replication mediated by a DNA-relaxing initiator protein and its interactions with the cognate DNA origin, (ii) lagging-strand origins of replication, (iii) antibiotic resistance genes, (iv) mobilization functions, (v) replication control, performed by proteins and/or antisense RNAs, and (vi) the participating host-encoded functions. The mobilization functions include a relaxase initiator of transfer (Mob), an origin of transfer, and one or two small auxiliary proteins. There is a family of relaxases, the MOB<sub>V</sub> family represented by plasmid pMV158, which has been revisited and updated. Family secrets, like a putative open reading frame of unknown function, are reported. We conclude that basic research on RCR plasmids is of importance, and our perspectives contemplate the concept of One Earth because we should incorporate bacteria into our daily life by diminishing their virulence and, at the same time, respecting their genetic diversity.</p>","PeriodicalId":18520,"journal":{"name":"Microbiology and Molecular Biology Reviews","volume":null,"pages":null},"PeriodicalIF":8.0000,"publicationDate":"2022-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8653906/pdf/mmbr.00222-20.pdf","citationCount":"6","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Microbiology and Molecular Biology Reviews","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1128/MMBR.00222-20","RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MICROBIOLOGY","Score":null,"Total":0}
引用次数: 6
Abstract
Plasmids are self-replicative DNA elements that are transferred between bacteria. Plasmids encode not only antibiotic resistance genes but also adaptive genes that allow their hosts to colonize new niches. Plasmid transfer is achieved by conjugation (or mobilization), phage-mediated transduction, and natural transformation. Thousands of plasmids use the rolling-circle mechanism for their propagation (RCR plasmids). They are ubiquitous, have a high copy number, exhibit a broad host range, and often can be mobilized among bacterial species. Based upon the replicon, RCR plasmids have been grouped into several families, the best known of them being pC194 and pUB110 (Rep_1 family), pMV158 and pE194 (Rep_2 family), and pT181 and pC221 (Rep_trans family). Genetic traits of RCR plasmids are analyzed concerning (i) replication mediated by a DNA-relaxing initiator protein and its interactions with the cognate DNA origin, (ii) lagging-strand origins of replication, (iii) antibiotic resistance genes, (iv) mobilization functions, (v) replication control, performed by proteins and/or antisense RNAs, and (vi) the participating host-encoded functions. The mobilization functions include a relaxase initiator of transfer (Mob), an origin of transfer, and one or two small auxiliary proteins. There is a family of relaxases, the MOBV family represented by plasmid pMV158, which has been revisited and updated. Family secrets, like a putative open reading frame of unknown function, are reported. We conclude that basic research on RCR plasmids is of importance, and our perspectives contemplate the concept of One Earth because we should incorporate bacteria into our daily life by diminishing their virulence and, at the same time, respecting their genetic diversity.
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.