Role of a P-type ATPase in metal efflux in Chromobacterium violaceum

• Grant number: 22/05740-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2022
• End date: December 31, 2024
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: José Freire da Silva Neto
• Grantee: Carolina Panosso Schuindt
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated research grant: 21/06894-0 - Bacterial transcription factors involved in metal homeostasis, oxidative stress and virulence: investigating how Chromobacterium violaceum switches from the environment to the host, AP.JP2
• Associated scholarship(s): 23/12144-9 - Role of Chromobacterium violaceum ZntA in defense against zinc intoxication imposed by Dictyostelium discoideum, BE.EP.IC

Abstract

Transition metals are essential micronutrients that act as cofactors of many proteins, but intracellular metal excess causes damage. In bacteria, metal homeostasis involves the coordinated action of transporters for metal uptake or metal efflux according to the metal availability. In this work, we propose to characterize the gene CV1154 that encodes a putative P1B4-type ATPase in Chromobacterium violaceum, an environmental opportunistic pathogen. We will investigate whether CV1154 functions as an efflux pump specific for iron or could be involved in the efflux of other metals such as zinc and copper. We will generate a mutant strain without the gene CV1154 by allelic exchange. This strain will be characterized for phenotypes of intracellular iron accumulation and susceptibility to iron intoxication and oxidative stress. The iron content of the mutant will be measured. Virulence tests will be performed in Galleria mellonella and/or mice. The expression of CV1154 will be evaluated in the presence of iron, other metals, and oxidants. The data obtained in this study will reveal whether the gene CV1154 acts as an iron efflux pump that contributes to the survival of C. violaceum under iron excess, including in the host.