Characterization of novel mechanisms of regulation and resistance to iron in Chromobacterium violaceum

• Grant number: 18/19058-2
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: December 01, 2019
• End date: April 30, 2023
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: José Freire da Silva Neto
• Grantee: Bianca Bontempi Batista
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated scholarship(s): 21/09170-2 - The role of a MarR family transcription factor in iron homeostasis in Chromobacterium violaceum, BE.EP.DR

Abstract

Iron is an essential micronutrient, required as cofactor in several biological reactions, but its intracellular excess can cause damage. In bacteria, iron homeostasis involves the activation of uptake systems in limitation and systems of efflux and storage in excess of this metal. In this work, we intend to identify and characterize novel regulatory mechanisms and efflux systems for iron in Chromobacterium violaceum, an environmental bacterium that occasionally causes serious infections in humans. The unbiased identification of novel transcription factors and efflux systems for iron will be performed by screening a library of transposon mutants for altered production of siderophores and for increased susceptible to iron excess, respectively. For the identified transcription factors, we will define their regulons and map their DNA binding sites by RNA-Seq and ChIP-Seq. The potential efflux systems identified will be characterized for their specificity to confer resistance and to export iron in relation to other metals. The role of these proteins in C. violaceum pathogenesis will be tested by virulence assays in mice with the mutants of the transposon library. The data obtained in this work should reveal if C. violaceum uses other metaloregulators besides Fur to regulate iron homeostasis and if there are systems that export and alleviate iron toxicity in this bacterium. (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)

RODRIGUES DE SOUZA SANTOS, RENATO ELIAS; BATISTA, BIANCA BONTEMPI; DA SILVA NETO, JOSE FREIRE. Ferric Uptake Regulator Fur Coordinates Siderophore Production and Defense against Iron Toxicity and Oxidative Stress and Contributes to Virulence in Chromobacterium violaceum. Applied and Environmental Microbiology, v. 86, n. 21, NOV 2020. (17/03342-0, 18/01388-6, 20/00259-8, 18/19058-2)

DE LIMA, VINICIUS M.; BATISTA, BIANCA B.; DA SILVA NETO, JOSE F.. The Regulatory Protein ChuP Connects Heme and Siderophore-Mediated Iron Acquisition Systems Required for Chromobacterium violaceum Virulence. FRONTIERS IN CELLULAR AND INFECTION MICROBIOLOGY, v. 12, p. 15-pg., 2022-05-11. (18/19058-2, 20/00259-8, 18/17716-2, 18/01388-6)

Academic Publications

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

BATISTA, Bianca Bontempi. Characterization of novel mechanisms of regulation and resistance to iron in Chromobacterium violaceum. 2023. Doctoral Thesis - Universidade de São Paulo (USP). Faculdade de Medicina de Ribeirão Preto (PCARP/BC) Ribeirão Preto.