Falagán Carmen, Foesel Bärbel, Johnson Barrie
College of Natural Sciences, Bangor University, Deiniol Road, Bangor, LL57 2UW, UK.
Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures, Inhoffenstrasse 7B, 38124, Brunswick, Germany.
Extremophiles. 2017 May;21(3):459-469. doi: 10.1007/s00792-017-0916-4. Epub 2017 Feb 22.
Four novel strains of Acidobacteria were isolated from water samples taken from pit lakes at two abandoned metal mines in the Iberian Pyrite Belt mining district, south-west Spain. Three of the isolates belong to the genus Acidicapsa (MCF9, MCF10, and MCF14) and one of them to the genus Granulicella (MCF40). All isolates are moderately acidophilic (pH growth optimum 3.8-4.1) and mesophilic (temperature growth optima 30-32 °C). Isolates MCF10 and MCF40 grew at pH lower (<3.0) than previously reported for all other acidobacteria. All four strains are obligate heterotrophs and metabolised a wide range of sugars. While all four isolates are obligate aerobes, MCF9, MCF10, and MCF14 catalysed the reductive dissolution of the ferric iron mineral schwertmannite when incubated under micro-aerobic conditions. Isolates MCF9 and MCF14 shared 99.5% similarity of their 16 S rRNA genes, and were considered to be strains of the same species. The major quinone of strains MCF10, MCF9, and MCF40 is MK-8, and their DNA G + C contents are 60.0, 59.7, and 62.1 mol%, respectively. Based on phylogenetic and phenotypic data, three novel species, Acidicapsa ferrireducens strain MCF9 (=DSM 28997 = NCCB 100575), Acidicapsa acidiphila strain MCF10 (=DSM 29819 = NCCB 100576), and Granulicella acidiphila strain MCF40 (DSM 28996 = NCCB 100577), are proposed.
从西班牙西南部伊比利亚黄铁矿带矿区两个废弃金属矿的矿坑湖采集的水样中分离出了4株新型嗜酸菌。其中3株分离菌属于嗜酸囊菌属（MCF9、MCF10和MCF14），1株属于粒状嗜酸菌属（MCF40）。所有分离菌均为中度嗜酸菌（最适生长pH为3.8 - 4.1）和嗜温菌（最适生长温度为30 - 32℃）。分离菌MCF10和MCF40能在比之前报道的所有其他嗜酸菌更低的pH值（<3.0）下生长。所有4株菌株均为专性异养菌，能代谢多种糖类。虽然所有4株分离菌均为专性需氧菌，但在微需氧条件下培养时，MCF9、MCF10和MCF14能催化铁矿物施韦策尔矿的还原溶解。分离菌MCF9和MCF14的16S rRNA基因相似度为99.5%，被认为是同一物种的菌株。菌株MCF10、MCF9和MCF40的主要醌为MK - 8，其DNA G + C含量分别为60.0、59.7和62.1 mol%。基于系统发育和表型数据，提出了3个新物种，即嗜酸铁还原嗜酸囊菌菌株MCF9（=DSM 28997 = NCCB 100575）、嗜酸嗜酸囊菌菌株MCF10（=DSM 29819 = NCCB 100576）和嗜酸粒状嗜酸菌菌株MCF40（DSM 28996 = NCCB 100577）。
