The relation between polyphosphate metabolism and the pst and pit genes of P. aeruginosa

• Grant number: 12/11537-2
• Support Opportunities: Scholarships in Brazil - Master
• Start date: January 01, 2013
• End date: October 31, 2014
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: Beny Spira
• Grantee: Nicolas Federico Villamil Munevar
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Phosphorus is an essential component of living things, but is not widely available in nature. To cope with phosphorus shortage, free-living bacteria carry several genes whose function is to take up and assimilate organic and inorganic phosphate (Pi) molecules. This genes are belong to the PHO regulon, and they collectively respond to the stimulus of environmental phosphate limitation. In Escherichia coli, Pseudomonas aeruginosa and other proteobacteria, there are at least two Pi transport systems; one of them is the Pi uptake system, Pst, which has high specificity for its substrate. Pst is encoded by an operon of the same name, that contains 5 genes; the four proximal genes encode the Pst transporter, while the last gene of the operon, phoU, encodes a protein whose exact function is unknown. Studies with phoU mutants showed that this gene is related to the repression of the PHO regulon, with polyphosphate accumulation and with intrinsic resistance to antibiotics and stresses. The other Pi transporter, Pit, is expressed constitutively and does not belong to the PHO regulon. The aim of this project is to examine some hypotheses that may explain the role of PhoU by linking the control of the PHO regulon with polyphosphate metabolism in P. aeruginosa. A potential effect of Pit on polyphosphate metabolism and on the repression of PHO regulon will be also investigated. Finally, the transcription pattern of the pst operon will be analyzed, in order to determine whether it form one or two transcriptional units. All of these phenomena may have practical effects on the genetical improvement of Pi uptake and polyphosphate accumulation in P. aeruginosa. (AU)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

MUNEVAR, Nicolas Federico Villamil. Analysis of the metabolism of polyphosphate and of the pst operon in Pseudomonas aeruginosa.. 2015. Master's Dissertation - Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI) São Paulo.