Determining the Zur regulon in Chromobacterium violaceum

• Grant number: 22/12782-2
• Support Opportunities: Scholarships in Brazil - Master
• Start date: October 01, 2022
• End date: September 30, 2024
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: José Freire da Silva Neto
• Grantee: Sergio Pereira Lima Neto
• 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

Abstract

The transition metal zinc is an essential micronutrient for all organisms due to its structural and catalytic function in several proteins. However, excess zinc causes intoxication by the mismetallation of proteins. The Zinc Uptake Regulator (Zur) controls at transcriptional level the zinc homeostasis in several bacteria. The discovery of the repertoire of Zur-regulated genes provides novel insights into zinc homeostasis. We determined previously that in the environmental pathogen Chromobacterium violaceum Zur represses an operon encoding the zinc importer ZnuABC, which is required for C. violaceum virulence. However, the entire repertoire of Zur-regulated genes of C. violaceum remains to be defined. In this work, we intend to define the C. violaceum Zur regulon by global transcriptome analysis to identify novel mechanisms of zinc homeostasis in this opportunistic pathogen. The Zur-regulated genes will be identified by RNA sequencing (RNA-seq) on C. violaceum wild-type and a zur mutant strain. Beta-galactosidase assays will be used to validate the RNA-seq data. The genes directly regulated by Zur will be defined by performing EMSA assays. Selected genes of the Zur regulon will be characterized, including for their role in C. violaceum virulence. A broader understanding of how C. violaceum manages zinc can provide us with strategies for dealing with opportunistic pathogens.