This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Wu, H. Articles by Ohtake, H. Search for Related Content PubMed PubMed Citation Articles by Wu, H. Articles by Ohtake, H. Pubmed/NCBI databases Gene GEO Profiles Protein Compound via MeSH Substance via MeSH

 Previous Article  |  Next Article 

Journal of Bacteriology, June 2000, p. 3400-3404, Vol. 182, No. 12
0021-9193/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.

Identification and Characterization of Two Chemotactic Transducers for Inorganic Phosphate in Pseudomonas aeruginosa

Hong Wu, Junichi Kato, Akio Kuroda, Tsukasa Ikeda, Noboru Takiguchi, and Hisao Ohtake^*

Department of Fermentation Technology, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8527, Japan

Received 18 January 2000/Accepted 23 March 2000

Two chemotactic transducers for inorganic phosphate (P_i), designated CtpH and CtpL, have been identified in Pseudomonas aeruginosa. The corresponding genes (ctpH and ctpL) were inactivated by inserting kanamycin and tetracycline resistance gene cassettes into the wild-type genes in the P. aeruginosa PAO1 genome. Computer-assisted capillary assays showed that the ctpH single mutant failed to exhibit P_i taxis when the concentration of P_i in the capillary was higher than 5 mM. Conversely, the ctpL single mutant could not respond to P_i at the concentration of 0.01 mM. The ctpH ctpL double mutant was defective in P_i taxis at any concentration ranging from 0.01 to 10 mM. To investigate regulation of P_i taxis, the ctpH and ctpL genes were also disrupted individually in the P. aeruginosa phoU and phoB single mutants. The ctpH phoU and ctpH phoB double mutants were defective in P_i taxis, regardless of whether the cells were starved for P_i. The ctpL phoU double mutant was constitutive for P_i taxis, whereas the ctpL phoB double mutant was induced by P_i limitation for P_i taxis. The region upstream of ctpL, but not ctpH, contained a putative pho box sequence. Expression of ctpL::lacZ was induced by P_i limitation in PAO1, while it was constitutive in the phoU mutant. In contrast, the phoB mutant showed only background levels of ctpL::lacZ expression. These results showed that ctpL is involved in the pho regulon genes in P. aeruginosa. The ctpH phoU mutant, which failed to exhibit P_i taxis, was constitutive for ctpL::lacZ expression, suggesting that the P_i detection by CtpL requires PhoU. Like PAO1, the phoB and phoU single mutants were constitutive for expression of ctpH::lacZ. Thus, the evidence that the ctpL phoU mutant, but not the ctpL phoB mutant and PAO1, was constitutive for P_i taxis raised the possibility that PhoU exerts a negative control on P_i detection by CtpH at the posttranscriptional level.

---

^* Corresponding author. Mailing address: Department of Fermentation Technology, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8527, Japan. Phone: 81-824-24-7756. Fax: 81-824-22-3758. E-mail: hohtake{at}ipc.hiroshima-u.ac.jp.

---

Journal of Bacteriology, June 2000, p. 3400-3404, Vol. 182, No. 12
0021-9193/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.

This article has been cited by other articles:

• Singh, A. K., Pindi, P. K., Dube, S., Sundareswaran, V. R., Shivaji, S. (2009). Importance of trmE for Growth of the Psychrophile Pseudomonas syringae at Low Temperatures. Appl. Environ. Microbiol. 75: 4419-4426 [Abstract] [Full Text]  
• Liu, X., Wood, P. L., Parales, J. V., Parales, R. E. (2009). Chemotaxis to Pyrimidines and Identification of a Cytosine Chemoreceptor in Pseudomonas putida. J. Bacteriol. 191: 2909-2916 [Abstract] [Full Text]  
• Alvarez-Ortega, C., Harwood, C. S. (2007). Identification of a Malate Chemoreceptor in Pseudomonas aeruginosa by Screening for Chemotaxis Defects in an Energy Taxis-Deficient Mutant. Appl. Environ. Microbiol. 73: 7793-7795 [Abstract] [Full Text]  
• Kim, H.-E., Shitashiro, M., Kuroda, A., Takiguchi, N., Ohtake, H., Kato, J. (2006). Identification and Characterization of the Chemotactic Transducer in Pseudomonas aeruginosa PAO1 for Positive Chemotaxis to Trichloroethylene.. J. Bacteriol. 188: 6700-6702 [Abstract] [Full Text]  
• Yuan, Z.-C., Zaheer, R., Morton, R., Finan, T. M. (2006). Genome prediction of PhoB regulated promoters in Sinorhizobium meliloti and twelve proteobacteria.. Nucleic Acids Res 34: 2686-2697 [Abstract] [Full Text]  
• Hong, C. S., Kuroda, A., Takiguchi, N., Ohtake, H., Kato, J. (2005). Expression of Pseudomonas aeruginosa aer-2, One of Two Aerotaxis Transducer Genes, Is Controlled by RpoS. J. Bacteriol. 187: 1533-1535 [Abstract] [Full Text]  
• Zhulin, I. B., Nikolskaya, A. N., Galperin, M. Y. (2003). Common Extracellular Sensory Domains in Transmembrane Receptors for Diverse Signal Transduction Pathways in Bacteria and Archaea. J. Bacteriol. 185: 285-294 [Abstract] [Full Text]  
• Ferrandez, A., Hawkins, A. C., Summerfield, D. T., Harwood, C. S. (2002). Cluster II che Genes from Pseudomonas aeruginosa Are Required for an Optimal Chemotactic Response. J. Bacteriol. 184: 4374-4383 [Abstract] [Full Text]  
• McCarter, L. L. (2001). Polar Flagellar Motility of the Vibrionaceae. Microbiol. Mol. Biol. Rev. 65: 445-462 [Abstract] [Full Text]  
• Croft, L., Beatson, S. A., Whitchurch, C. B., Huang, B., Blakeley, R. L., Mattick, J. S. (2000). An interactive web-based Pseudomonas aeruginosa genome database: discovery of new genes, pathways and structures. Microbiology 146: 2351-2364 [Abstract] [Full Text]