Effects of Mg2 + on the phoU mutant Pseudomonas aeruginosa

• Grant number: 15/24942-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2016
• End date: July 31, 2018
• Field of knowledge: Biological Sciences - Microbiology - Biology and Physiology of Microorganisms
• Principal Investigator: Beny Spira
• Grantee: Nicole Gonçalves Picinin
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Bacteria take up phosphate (Pi) from the medium through two transport systems, the main one is the Pst system. The Pst system is encoded by a five-genes operon, the first four genes, pstS, pstC, pstA and pstB encode proteins that are actively involved in Pi transport. The function of the fifth and most distal gene, phoU, has not yet been elucidated. Inorganic polyphosphate (PolyP) is a linear polymer in which various Pi monomers are linked together by phosphoanydride bonds. It is known that PolyP chelates magnesium, which might result in the intracellular depletion of this element, having a negative impact on protein synthesis. It has been shown in our laboratory that the phoU mutant of Pseudomonas aeruginosa grows slower and to lower yields, but accumulates up to three times more PolyP then the wild type strain. In addition; the phoU mutant is more sensitive to environmental stresses and antibiotics. In this project the relation between magnesium availability and the pleiotropic effects of the phoU mutation will be evaluated.