CLONING AND CHARACTERIZATION OF A PSEUDOMONAS-AERUGINOSA GENE INVOLVED IN THE NEGATIVE REGULATION OF PHOSPHATE TAXIS

Pseudomonas aeruginosa PAO1 exhibited a positive chemotactic response to P-i. The chemotactic response was induced by P-i limitation. An alkaline phosphatase (AP) constitutive mutant showed a chemotactic response to P-i regardless of whether the cells were starved for P-i. Sequence analysis and complementation studies showed that the P. aeruginosa phoU gene was involved both in the regulation of AP expression and in the induction of P-i taxis. However, unlike AP expression, P-i taxis was not regulated by the phoB gene product.