Unraveling the biological role of LsfA, a 1-Cys Prx involved in the P. aeruginosa virulence

• Grant number: 20/00845-4
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: July 01, 2020
• End date: February 28, 2023
• Field of knowledge: Biological Sciences - Biochemistry - Biochemistry of Microorganisms
• Principal Investigator: Luis Eduardo Soares Netto
• Grantee: Rogério Luis Aleixo Silva
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 13/07937-8 - Redoxome - Redox Processes in Biomedicine, AP.CEPID
• Associated scholarship(s): 21/11077-0 - LsfA in inflammation: roles of an antioxidant protein in pro-inflammatory and pro-resolving lipid mediators, BE.EP.DR

Abstract

Pseudomonas aeruginosa is a ubiquitous, gamma-proteobacteria, which are the main cause of nosocomial infection among all pathogens related to Pneumonia in the Intensive Care Unit. Among the various host's defense mechanisms, we are interested in the release of reactive oxygen and nitrogen species by phagocytes. LsfA belongs to the peroxiredoxin (Prx) family and to the subgroup that contains only one catalytic cysteine (so-called 1-Cys Prx). Prxs are enzymes capable of removing peroxides (including peroxynitrite) at very high rates. As LsfA is related to the P. aeruginosa virulence, during my master's degree I carried out studies characterizing this antioxidant enzyme biochemically and structurally. Within this context, the objective of the present work is to further advance this characterization, now determining the rate constants of LsfA with organic peroxides of biological occurrence. Moreover, we intend to correlate this kinetic information with the investigation of the LsfA role in the response of P. aeruginosa to distinct oxidants. We also aim to identify the biological reductant (s) of LsfA, and if possible determine the crystallographic structure of this antioxidant enzyme complexed with its possible reductants. Having characterized LsfA in detail, we will be able to search for possible LsfA inhibitors, employing in vitro and in vivo assays. Among the analyzes of LsfA in cellular systems, we intend to verify: (a) the expression of this protein in response to different types of oxidative stress; (b) the importance of LsfA in the physiology of the bacterium; (c) possible cellular partners; (d) survival of P. aeruginosa strains with mutations in the LsfA gene in bacterial and neutrophil co-cultures. (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)

DE OLIVEIRA, MARCOS ANTONIO; TAIRUM, CARLOS A.; SOARES NETTO, LUIS EDUARDO; PIRES DE OLIVEIRA, ANA LAURA; ALEIXO-SILVA, ROGERIO LUIS; MONTANHERO CABRERA, VITORIA ISABELA; BREYER, CARLOS A.; DOS SANTOS, MELINA CARDOSO. Relevance of peroxiredoxins in pathogenic microorganisms. Applied Microbiology and Biotechnology, v. 105, n. 14-15, JUL 2021. (20/00845-4, 17/06263-4, 13/07937-8, 20/02868-1, 16/15849-0, 11/13500-6, 17/19942-7, 19/04054-4)

SILVA, ROGERIO ALEIXO; DOMINGOS, RENATO; NETTO, LUIS. Specific reduction of a 1-Cys Prx from Pseudomonas aeruginosa by ascorbate. FASEB JOURNAL, v. 35, p. 2-pg., 2021-05-01. (13/07937-8, 20/00845-4)

Academic Publications

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

SILVA, Rogério Luis Aleixo. Unraveling the biological role of LsfA, a 1-Cys Prx involved in the Pseudomonas aeruginosa virulence. 2023. Doctoral Thesis - Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB) São Paulo.