title: Influence of ptsP gene on pyocyanin production in Pseudomonas aeruginosa.
abstract: A pyocyanin overproducer with insertional inactivation of ptsP gene was isolated from a mini-Mu insertion library in Pseudomonas aeruginosa PA68. The mutation was complemented by a functional ptsP gene in trans. The pyocyanin-overproducing phenotype was also found in a ptsP mutant constructed by gene replacement in the P. aeruginosa PAO1 strain. Reporter plasmids with P(qscR)-lacZ, P(lasI)-lacZ and P(rhlI)-lacZ were constructed and the beta-galactosidase activity in the ptsP mutant/wild-type background was measured. The results showed that lack of Enzyme I(Ntr) (EI(Ntr), encoded by ptsP) decreased transcription from the P(qscR) promoter and increased the activity of the P(lasI) and P(rhlI) promoters. Normally, QscR represses the quorum-sensing LasR-LasI and RhlR-RhlI systems involved in pyocyanin regulation. Our results showed that the ptsP gene has an important role in the regulation of pyocyanin production and that two quorum-sensing systems and their repressor QscR are involved in this regulation.
authors.affiliation: Tianjin Key Laboratory of Microbiology, College of Life Sciences, Nankai University, Tianjin 300071, PR China.
authors.forename: Haijin
authors.initials: H
authors.lastname: Xu
authors.forename: Weili
authors.initials: W
authors.lastname: Lin
authors.forename: Huiming
authors.initials: H
authors.lastname: Xia
authors.forename: Shuwa
authors.initials: S
authors.lastname: Xu
authors.forename: Yingli
authors.initials: Y
authors.lastname: Li
authors.forename: Hongming
authors.initials: H
authors.lastname: Yao
authors.forename: Fang
authors.initials: F
authors.lastname: Bai
authors.forename: Xiuming
authors.initials: X
authors.lastname: Zhang
authors.forename: Yanling
authors.initials: Y
authors.lastname: Bai
authors.forename: Per
authors.initials: P
authors.lastname: Saris
authors.forename: Mingqiang
authors.initials: M
authors.lastname: Qiao
mesh_terms: D001483:Base Sequence; D004269:DNA, Bacterial / Q000235:genetics; D015870:Gene Expression; D005798:Genes, Bacterial; D017930:Genes, Reporter; D005816:Genetic Complementation Test; D007700:Kinetics; D007763:Lac Operon; D016254:Mutagenesis, Insertional; D010641:Phenotype; D011401:Promoter Regions, Genetic; D011550:Pseudomonas aeruginosa / Q000235:genetics* / Q000378:metabolism*; D011710:Pyocyanine / Q000096:biosynthesis*
chemical_list: D004269:DNA, Bacterial; D011710:Pyocyanine