Potential of tellurite resistance in heterotrophic bacteria from mining environments

Pedro Farias; Romeu Francisco; Paula V Morais

doi:10.1016/j.isci.2022.104566

Potential of tellurite resistance in heterotrophic bacteria from mining environments

iScience. 2022 Jun 9;25(7):104566. doi: 10.1016/j.isci.2022.104566. eCollection 2022 Jul 15.

Authors

Pedro Farias¹, Romeu Francisco¹, Paula V Morais¹

Affiliation

¹ University of Coimbra, Centre for Mechanical Engineering, Materials and Processes, Department of Life Sciences, 3000-456 Coimbra, Portugal.

Abstract

Untreated mining wastes and improper disposal of high-tech devices generate an environmental increase of bioavailable metalloids, exerting stress on autochthonous microbial populations. Tellurium is a metalloid, an element with raising economic importance; nevertheless, its interaction with living organisms is not yet fully understood. Here we characterized aerobic heterotrophic bacteria, isolated from high metal-content mining residues, able to resist/reduce tellurite into tellurium structures and to determine the presence of confirmed tellurite resistance genetic determinants in resistant strains. We identified over 50 tellurite-resistant strains, among 144 isolates, eight strains reduced tellurite to tellurium at different rates, with the concomitant production of tellurium deposits. Most tellurite resistance genes were found in strains from Bacillales, with the prevalence of genes of the ter operon. This work demonstrated that bacterial isolates, from environments with a persistent selective pressure, are potential candidates for uncovering strategies for tellurite resistance and/or production of valuable Te-containing materials.

Keywords: Bacteriology; Biogeoscience; Microbiology.