Acid mine drainage occurs due to the chemical and microbiological oxidation of sulfide minerals and can be a source of potentially toxic elements contamination of groundwater and surface water. The objective of this study was to identify microorganisms involved in sulfide oxidation in the tailings of a Bahia Gold Belt mine (Brazil). Samples of solids and water were collected at the mine tailings dam and characterized. The microorganisms were isolated after enrichment and subsequent purification. The major constituents of the tailings are Si, Fe, Al, S, and K. The sulfur content of the tailings is 0.98%. The major phases are quartz, muscovite, and clinochlore. Gravity concentrates of the tailings show several particles of pyrite, that is, the major sulfide phase. Molecular analysis identified the microorganisms isolated in the acid mine drainage process in this region. Five bacterium species were found: Acidithiobacillus spp., Acidithiobacillus ferrooxidans, Acidiphilium spp., Leptospirillum type II, and Sulfobacillus spp. No organisms of the archaea or eukaryote domains were found. The isolate was used in the bioleaching of copper sulfide ore, and the copper extraction was about 60% in 60 days for ground ore.

酸性矿山的排水是由于硫化物矿物的化学和微生物氧化而发生的，并且可能是地下水和地表水污染的潜在有毒元素的来源。这项研究的目的是确定在巴伊亚金带矿（巴西）的尾矿中涉及硫化物氧化的微生物。在矿山尾矿坝收集了固体和水的样品并进行了表征。富集并随后纯化后分离微生物。尾矿的主要成分是Si，Fe，Al，S和K。尾矿中的硫含量为0.98％。主要相为石英，白云母和斜绿石。尾矿的重力精矿显示出几个黄铁矿颗粒，即主要的硫化物相。分子分析确定了该地区酸性矿山排水过程中分离出的微生物。发现了五种细菌：嗜酸菌，氧化亚铁硫杆菌，Acidiphilium属，钩端螺旋体II型，和硫化杆菌属。没有发现古细菌或真核生物域的生物。该分离物用于硫化铜矿石的生物浸出，地面矿石的铜提取率在60天内约为60％。