Polyphosphate accumulation and the role of phoU in Pseudomonas aeruginosa

• Grant number: 11/07775-2
• Support Opportunities: Regular Research Grants
• Start date: July 01, 2011
• End date: December 31, 2013
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: Beny Spira
• Grantee: Beny Spira
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Phosphorous is a vital element present in all living beings. It is not readily available in nature and it is generally found in the form of orthophosphate (Pi). Bacteria carry several genes related to the uptake and assimilation of Pi. Escherichia coli, Pseudomonas aeroginosa and other Proteobacteria possess at least two different systems for Pi uptake. The main one- Pst, displays high affinity for Pi and is encoded by the pst operon, which contains five genes. The four proximal genes of pst encode the proteins related to Pi transport, and the last gene of the operon-phoU, encodes a protein whose precise function is unknown. Studies with phoU mutants have shown that this gene plays a role in the repression of the PHO regulon, polyphosphate accumulation and intrinsic resistance to antibiotics and environmental stresses. Polyphosphate (PPi) is a polymer made of dozens or hundreds of Pi molecules connected by high-energy chemical bonds. PPi is present in all cells and has several functions, such as Pi and energy storage, resistance to environmental stresses and chelation of heavy metals. In the present study, several aspects of P. aeruginosa pst expression and regulation will be investigated. We will focus on the transcription pattern of the pst operon, and the relationship of phoU with PPi accumulation, stress and antibiotic resistance. Another proposal of this project is to enhance Pi uptake and PPi accumulation in P. aeruginosa by means of genetic engineering and by directed-evolution. This part of the project aims at developing a solution to the problem of eutrophication and at hte same time to devise an alternative to the mineral extraction of phosphate by recycling of Pi-contaminated waters. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

THOMAZ, LUCIANA; DE ALMEIDA, LUIZ GUSTAVO; SILVA, FLAVIA R. O.; CORTEZ, MAURO; TABORDA, CARLOS P.; SPIRA, BENY. In vivo Activity of Silver Nanoparticles Against Pseudomonas aeruginosa Infection in Galleria mellonella. FRONTIERS IN MICROBIOLOGY, v. 11, NOV 9 2020. (12/24105-3, 15/06547-7, 16/08730-6, 11/07775-2, 14/09143-1)