The genes zntA and zntR encoding a P-type ATPase and its activator confer zinc and cadmium resistance in Chromobacterium violaceum
Year: 2026
Type: article
Abstract: The transition metal zinc is an essential trace element for life but becomes toxic at high concentrations. In the opportunistic pathogen Chromobacterium violaceum , zinc acquisition is crucial for virulence, yet how this bacterium copes with zinc toxicity remains unknown. In this work, we demonstrate that C. violaceum senses and responds to excess zinc by activating the zntA gene, which encodes a P 1B-2 -type ATPase, via the transcriptional regulator ZntR. Phenotypic analyses by growth curves, disk diffusion, and CFU assays revealed that both Δ zntA or Δ zntR mutant strains exhibited increased sensitivity to zinc and cadmium. The Δ zntA mutant showed increased zinc and cadmium accumulation, suggesting that ZntA functions as an efflux pump. The expression of zntA increased in the presence of zinc and cadmium in the wild-type strain, but not in the Δ zntR mutant strain, indicating that ZntR activates zntA under conditions of zinc or cadmium excess. The role of ZntA in vivo was analyzed using the social amoeba Dictyostelium discoideum as a host cell. Plaque assays indicated that the C. violaceum Δ zntA mutant strain was more susceptible than the C. violaceum wild-type strain to clearance by D. discoideum knockout strains with altered intracellular zinc allocation. Overall, our data reveal that the genes zntA and zntR encoding a P 1B-2 -type ATPase and its transcriptional activator are key determinants of zinc and cadmium resistance in C. violaceum , ensuring bacterial survival under zinc-stress conditions encountered in the environment and the host.
Source: BioMetals
Institutions: Universidade de São Paulo, University of Geneva
Language: English
Subfield: Genetics
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $4,090
Funders: National Science Foundation, Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, Fundação de Amparo à Pesquisa do Estado de São Paulo, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Conselho Nacional de Desenvolvimento Científico e Tecnológico, Universidade de São Paulo, Fundação de Apoio ao Ensino, Pesquisa e Assistência do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo
Awards: G22113365, Der touristische Arbeitsmarkt: Angebot, Nachfrage und Steuerungsmöglichkeiten, G5644312937, Molecular mechanisms of the Xanthomonas citri resistance to Dictyostelium discoideum predation and the role of the Type VI Secretion System, G6438247056, G692793031, Bacterial transcription factors involved in metal homeostasis, oxidative stress and virulence: investigating how Chromobacterium violaceum switches from the environment to the host, G7673248907
OpenAlex ID: W7162122153