title: Positive regulation of pyoluteorin biosynthesis in Pseudomonas sp. M18 by quorum-sensing regulator VqsR.
abstract: The biocontrol rhizobacterium Pseudomonas sp. M18 can produce two kinds of antibiotics, namely pyoluteorin (Plt) and phenazine-1-carboxylic acid (PCA), and is antagonistic against a number of soilborne phytopathogens. In this study, a luxR-type quorum-sensing regulatory gene, vqsR, was identified and characterized immediately downstream of the Plt gene cluster in strain M18. A vqsR-inactivated mutant led to a significant decrease in the production of Plt and its biosynthetic gene expression. However, this was restored when introducing the vqsR gene by cloning into the plasmid pME6032 in trans. The vqsR mutation did not exert any obvious influence on the production of PCA and its biosynthetic gene expression and the production of Nacylhomoserine lactones (C4 and C8-HSLs) and their biosynthetic gene rhlI expression. Accordingly, these results introduce VqsR as a regulator of Plt production in Pseudomonas spp., and suggest that the regulatory mechanism of vqsR in strain M18 is distinct from that in P. aeruginosa. In addition, it was demonstrated that vqsR mutation did not have any obvious impact on the expression of Plt-specific ABC transporters and other secondary metabolic global regulators, including GacA, RpoS, and RsmA.
authors.affiliation: Key Laboratory of Microbial Metabolism, Ministry of Education, College of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, PR China.
authors.forename: Xianqing
authors.initials: X
authors.lastname: Huang
authors.forename: Xuehong
authors.initials: X
authors.lastname: Zhang
authors.forename: Yuquqn
authors.initials: Y
authors.lastname: Xu
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism; D000900:Anti-Bacterial Agents / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D020868:Gene Silencing; D005809:Genes, Regulator; D008969:Molecular Sequence Data; D010619:Phenazines / Q000378:metabolism; D010636:Phenols / Q000378:metabolism*; D011549:Pseudomonas / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D011758:Pyrroles / Q000378:metabolism*; D053038:Quorum Sensing; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism*
chemical_list: D018528:ATP-Binding Cassette Transporters; D000900:Anti-Bacterial Agents; D010619:Phenazines; D010636:Phenols; D011758:Pyrroles; D012097:Repressor Proteins; D015534:Trans-Activators; C095503:pyoluteorin; C064778:LuxR autoinducer binding proteins; C037165:1-phenazinecarboxylic acid