Phenazine antibiotic biosynthesis in Pseudomonas aureofaciens 30-84 is regulated by PhzR in response to cell density.

摘要: We have identified a gene that acts in trans to activate the expression of phenazine biosynthetic genes biological control organism Pseudomonas aureofaciens 30-84. This gene, phzR (phenazine regulator), is located upstream and divergently transcribed from genes. Thus, locus consists at least two operons. A functional required for production. The nucleotide sequence revealed an open reading frame 723 nucleotides encoding protein ca. 27 kDa. predicted amino acid PhzR has homology with other bacterial positive transcriptional activators, including LasR aeruginosa, LuxR Vibrio fischerii, TraR Agrobacterium tumefaciens. addition cell-free supernatants late-exponential-phase cultures strain 30-84 resulted genomic phzB:lacZ reporter lower cell density than normal, indicating possible presence autoinducer. These results indicate member two-component sensor-regulator family known or carboxy-terminal DNA-binding domains which regulates response environmental signals.