title: ChpA Controls Twitching Motility and Broadly Affects Gene Expression in the Biological Control Agent Lysobacter enzymogenes.
abstract: Lysobacter enzymogenes (L. enzymogenes) is an agriculturally important Gram-negative bacterium that employs T4P (type IV pili)-driven twitching motility to exhibit its antifungal function. Yet, it is still unclear how this bacterium regulates its twitching motility. Here, by using strain OH11 as the working model organism, we showed that a hybrid two-component system ChpA acts as a positive regulator in controlling twitching motility in L. enzymogenes. ChpA is a hybrid TCS (two-component transduction system) contains 7 domains including those for auto-phosphorylation and phosphate group transfer, as well as a phosphate receiver (REC) domain. Mutation of chpA completely abolished the wild-type twitching motility, as evidenced by the absence of mobile cells at the margin of the mutant colonies. Further studies of domain-deletion and phenotypic characterization reveal that domains responsible for phosphorylation and phosphotransfer, but not the REC domain, were indispensable for ChpA in regulating twitching motility. Transcriptome analyses of the chpA knockout strain indicated that ChpA was extensively involved in controlling expression of a wide variety of genes (totaling 243). The products of these differentially expressed genes were involved in multiple physiological and biological functions in L. enzymogenes. Thus, we have not only identified a new regulator controlling twitching motility in L. enzymogenes, but also provided the first report demonstrating the broad impact of the conserved ChpA in gene regulation in Gram-negative bacteria.
authors.affiliation: College of Plant Protection (Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, No. 1 Weigang, Nanjing, 210095, Jiangsu, People's Republic of China.
authors.forename: Mimi
authors.initials: M
authors.lastname: Zhou
authors.affiliation: College of Plant Protection (Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, No. 1 Weigang, Nanjing, 210095, Jiangsu, People's Republic of China.
authors.forename: Danyu
authors.initials: D
authors.lastname: Shen
authors.affiliation: College of Plant Protection (Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, No. 1 Weigang, Nanjing, 210095, Jiangsu, People's Republic of China.
authors.forename: Gaoge
authors.initials: G
authors.lastname: Xu
authors.affiliation: Institute of Plant Protection, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, People's Republic of China.
authors.forename: Fengquan
authors.initials: F
authors.lastname: Liu
authors.affiliation: College of Plant Protection (Key Laboratory of Integrated Management of Crop Diseases and Pests), Nanjing Agricultural University, No. 1 Weigang, Nanjing, 210095, Jiangsu, People's Republic of China. glqian@njau.edu.cn.
authors.forename: Guoliang
authors.initials: G
authors.lastname: Qian
mesh_terms: D000898:Antibiosis; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D061046:Biological Control Agents; D019295:Computational Biology / Q000379:methods; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D023061:Gene Order; D053528:Lysobacter / Q000502:physiology*; D009154:Mutation; D010766:Phosphorylation; D000072417:Protein Domains / Q000235:genetics; D059467:Transcriptome
chemical_list: D001426:Bacterial Proteins; D061046:Biological Control Agents
keywords: Biological control; ChpA; Lysobacter; T4P; Twitching motility