Essential role of extracytoplasmic proteins in the resistance of Gluconacetobacter diazotrophicus to cadmium.

Research in microbiology 2022 May-Jun

filter terms:

Cadmium (Cd) is a heavy metal used as raw material for several fertilizers and pesticides. The increase of Cd concentration in soils has been observed in cultivated areas, affecting animals, plants, and microorganisms. Gluconacetobacter diazotrophicus is a plant growth-promoting bacterium able to survive under adverse environmental conditions. Here, we investigated key mechanisms involved with the resistance of G. diazotrophicus to Cd. Proteomic analyses revealed that the main pathways regulated in response to Cd are nutrient uptake, multidrug efflux pumps, response to oxidative stress, and protein quality control system. Extracytoplasmic proteins related to multidrug efflux pumps were up-accumulated, while several proteins related to nutrients uptake were down-accumulated. The relevance of these pathways for bacterial resistance to Cd was investigated by reverse genetic analysis using mutants defective for nutrient uptake (tdbr, ompW, and oprB), multidrug efflux (czcC), response to oxidative stress (ggt), and protein quality control system (clpX). Our data demonstrated the essential role of the tdbr and czcC genes for resistance to Cd in G. diazotrophicus. These results contribute to a better understanding of the resistance mechanisms to Cd in G. diazotrophicus, shedding light on responses associated with extracytoplasmic compartments. Copyright © 2022 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Citation

Júlia Rosa Moreira, Mariana Ramos Leandro, Luciano de Souza Vespoli, Leandro Fernandes Andrade, Vivian Ribeiro Pimentel, Fabiano Silva Soares, Suzane Ariádina de Souza, Aline Chaves Intorne, Vanildo Silveira, Gonçalo Apolinário de Souza Filho. Essential role of extracytoplasmic proteins in the resistance of Gluconacetobacter diazotrophicus to cadmium. Research in microbiology. 2022 May-Jun;173(4-5):103922