Environmental Microbiology, Institute of Biosciences, TU Bergakademie Freiberg, Leipziger Str. 29, 09599 Freiberg, Germany.
Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures GmbH Dept. Bioinformatics, IT and Databases, Inhoffenstraße 7B, 38124 Braunschweig, Germany.
Res Microbiol. 2024 Jan-Feb;175(1-2):104150. doi: 10.1016/j.resmic.2023.104150. Epub 2023 Nov 4.
Many acidophilic iron-oxidizing bacteria used in the mining industry for the bioleaching of sulfidic minerals are intolerant to high chloride concentrations, resulting in problems where chloride occurs in the deposit at high concentrations or only seawater is available. In search for strains tolerating such conditions a tetrathionate- and iron-oxidizing bacterium was isolated from a tailings-contaminated beach sample at Portman Bay, Cartagena-La Union mining district, Spain, in the presence of 20 g l (0.34 M) sodium chloride. The isolate was able to form spores, did not grow in the absence of NaCl, and oxidized ferrous iron in the presence of up to 1.5 M (∼87 g l) NaCl. Genome sequencing based on a combination of Illumina and PacBio reads revealed two contigs, a circular bacterial chromosome of 5.2 Mbp and a plasmid of 90 kbp, respectively. The chromosome comprised seven different 16S rRNA genes. Submission of the chromosome to the Type (Strain) Genome Server (TYGS) without preselection of similar sequences revealed exclusively type strains of the genus Alicyclobacillus. In the TYGS analyses the respective most similar species were dependent on whether the final tree was derived from just 16S rRNA, from the genomes, or from the proteomes. Thus, TYGS analysis clearly showed that isolate SO9 represents a novel species of the genus Alicyclobacillus. In the presence of artificial seawater with almost 0.6 M chloride, the addition of Alicyclobacillus sp. SO9 improved copper dissolution from chalcopyrite (CuFeS) compared to abiotic leaching without bacteria. The new isolate SO9, therefore, has potential for bioleaching at elevated chloride concentrations.
许多用于硫化物矿物生物浸出的嗜酸氧化铁细菌无法耐受高浓度的氯化物，导致在矿床中氯化物浓度较高或只有海水可用的情况下出现问题。为了寻找耐受这种条件的菌株，从西班牙卡塔赫纳-拉联合矿区波特曼湾受尾矿污染的海滩样本中分离到一株硫代四酸盐和氧化铁细菌，该样本中存在 20 g/L（0.34 M）的氯化钠。该分离株能够形成孢子，在没有 NaCl 的情况下无法生长，并且在高达 1.5 M（约 87 g/L）的 NaCl 存在下能够氧化亚铁。基于 Illumina 和 PacBio 读数的组合进行的基因组测序揭示了两个连续体，分别是 5.2 Mbp 的圆形细菌染色体和 90 kbp 的质粒。染色体包含七个不同的 16S rRNA 基因。将染色体提交给 Type（Strain）基因组服务器（TYGS），而不预先选择类似序列，结果仅显示 Alicyclobacillus 属的模式菌株。在 TYGS 分析中，最相似的相应物种取决于最终树是仅基于 16S rRNA、基因组还是蛋白质组得出的。因此，TYGS 分析清楚地表明，分离株 SO9 代表 Alicyclobacillus 属的一个新种。在含有近 0.6 M 氯化物的人工海水中，与无细菌的生物浸出相比，添加 Alicyclobacillus sp. SO9 可提高从黄铜矿（CuFeS）中溶解铜。因此，新的分离株 SO9 具有在高氯化物浓度下进行生物浸出的潜力。
