气候变化领域集成服务门户(CCPortal): Conjugative plasmid-encoded toxin–antitoxin system PrpT/PrpA directly controls plasmid copy number

CCPortal

DOI	10.1073/pnas.2011577118
	Conjugative plasmid-encoded toxin–antitoxin system PrpT/PrpA directly controls plasmid copy number
	Ni S.; Li B.; Tang K.; Yao J.; Wood T.K.; Wang P.; Wang X.
发表日期	2021
ISSN	00278424
卷号	118 期号:4
英文摘要	Toxin–antitoxin (TA) loci were initially identified on conjugative plasmids, and one function of plasmid-encoded TA systems is to stabilize plasmids or increase plasmid competition via postsegregational killing. Here, we discovered that the type II TA system, Pseudoalteromonas rubra plasmid toxin–antitoxin PrpT/PrpA, on a low-copy-number conjugative plasmid, directly controls plasmid replication. Toxin PrpT resembles ParE of plasmid RK2 while antitoxin PrpA (PF03693) shares no similarity with previously characterized antitoxins. Surprisingly, deleting this prpA-prpT operon from the plasmid does not result in plasmid segregational loss, but greatly increases plasmid copy number. Mechanistically, the antitoxin PrpA functions as a negative regulator of plasmid replication, by binding to the iterons in the plasmid origin that inhibits the binding of the replication initiator to the iterons. We also demonstrated that PrpA is produced at a higher level than PrpT to prevent the plasmid from overreplicating, while partial or complete degradation of labile PrpA derepresses plasmid replication. Importantly, the PrpT/PrpA TA system is conserved and is widespread on many conjugative plasmids. Altogether, we discovered a function of a plasmid-encoded TA system that provides new insights into the physiological significance of TA systems. © 2021 National Academy of Sciences. All rights reserved.
英文关键词	Origin of replication; ParE; Plasmid copy number; Plasmid replication; Toxin–antitoxin
语种	英语
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/180872
作者单位	Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, Innovation Academy of South China Sea Ecology and Environmental Engineering, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Nansha District, Guangzhou, 511458, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Nansha District, Guangzhou, 511458, China; Key Laboratory of Comprehensive Utilization of Advantage Plants Resources in Hunan South, College of Chemistry and Bioengineering, Hunan University of Science and Engineering, 425199 Yongzhou, Hunan, China; Department of Chemical Engineering, Pennsylvania State University, University Park, PA 16802-4400, United States; University of Chinese Academy of Sciences, Beijing, 100049, China
推荐引用方式 GB/T 7714	Ni S.,Li B.,Tang K.,等. Conjugative plasmid-encoded toxin–antitoxin system PrpT/PrpA directly controls plasmid copy number[J],2021,118(4).
APA	Ni S..,Li B..,Tang K..,Yao J..,Wood T.K..,...&Wang X..(2021).Conjugative plasmid-encoded toxin–antitoxin system PrpT/PrpA directly controls plasmid copy number.Proceedings of the National Academy of Sciences of the United States of America,118(4).
MLA	Ni S.,et al."Conjugative plasmid-encoded toxin–antitoxin system PrpT/PrpA directly controls plasmid copy number".Proceedings of the National Academy of Sciences of the United States of America 118.4(2021).