Farias Pedro, Francisco Romeu, Morais Paula V
University of Coimbra, Centre for Mechanical Engineering, Materials and Processes, Department of Life Sciences, 3000-456 Coimbra, Portugal.
iScience. 2022 Jun 9;25(7):104566. doi: 10.1016/j.isci.2022.104566. eCollection 2022 Jul 15.
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 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.
未经处理的采矿废料和高科技设备的不当处置导致环境中生物可利用类金属增加，对本地微生物种群造成压力。碲是一种类金属，一种经济重要性不断提高的元素；然而，其与生物体的相互作用尚未完全了解。在这里，我们对从高金属含量的采矿残渣中分离出的好氧异养细菌进行了表征，这些细菌能够将亚碲酸盐抵抗/还原为碲结构，并确定抗性菌株中已确认的亚碲酸盐抗性遗传决定因素的存在。我们在144株分离物中鉴定出50多株抗亚碲酸盐菌株，其中8株以不同速率将亚碲酸盐还原为碲，并伴有碲沉积物的产生。大多数亚碲酸盐抗性基因存在于芽孢杆菌纲的菌株中，以 操纵子的基因最为普遍。这项工作表明，来自具有持续选择压力环境的细菌分离物是揭示亚碲酸盐抗性策略和/或生产有价值的含碲材料的潜在候选者。
