%0 Journal Article %A Lee, Yunho %A Yeom, Jinki %A Kim, Jisun %A Jung, Jaejoon %A Jeon, Che Ok %A Park, Woojun %T Phenotypic and physiological alterations by heterologous acylhomoserine lactone synthase expression in Pseudomonas putida %D 2010 %J Microbiology, %V 156 %N 12 %P 3762-3772 %@ 1465-2080 %R https://doi.org/10.1099/mic.0.041095-0 %K HSL, 3-oxo-C6-homoserine lactone %K AHL, N-acylhomoserine lactone %K QS, quorum sensing %K CFS, cell-free supernatants %K HGT, horizontal gene transfer %K HHL, N-hexanoyl homoserine lactone %I Microbiology Society, %X Many bacteria harbour an incomplete quorum-sensing (QS) system, whereby they possess LuxR homologues without the QS acylhomoserine lactone (AHL) synthase, which is encoded by a luxI homologue. An artificial AHL-producing plasmid was constructed using a cviI gene encoding the C6-AHL [N-hexanoyl homoserine lactone (HHL)] synthase from Chromobacterium violaceum, and was introduced successfully into both the wild-type and a ppoR (luxR homologue) mutant of Pseudomonas putida. Our data provide evidence to suggest that the PpoR–HHL complex, but neither PpoR nor HHL alone, could attenuate growth, antibiotic resistance and biofilm formation ability. In contrast, swimming motility, siderophore production and indole degradation were enhanced by PpoR–HHL. The addition of exogenous indole increased biofilm formation and reduced swimming motility. Interestingly, indole proved ineffective in the presence of PpoR–HHL, thereby suggesting that the PpoR–HHL complex masks the effects of indole. Our data were supported by transcriptome analyses, which showed that the presence of the plasmid-encoded AHL synthase altered the expression of many genes on the chromosome in strain KT2440. Our results showed that heterologous luxI expression that occurs via horizontal gene transfer can regulate a broad range of specific target genes, resulting in alterations of the phenotype and physiology of host cells. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.041095-0