Acidiphilium属菌DX-A的分离鉴定及其浸矿功能

Isolation and identification of Acidiphilium strain DX-A and function of its bioleaching

从江西德兴铜矿酸性矿坑水中分离得到1株嗜酸细菌（命名为DX-A）,该菌株为革兰氏阴性菌,短杆状,菌体宽×长为（0.45-0.55）μm×（1.1-2.1）μm,最适生长pH为3.5,最适生长温度为30℃。该菌能利用FeCl3及多种硫化矿和葡萄糖等多种有机物进行生长,但是不能利用FeSO4进行生长,因而该菌为兼性异养型细菌。构建该菌的系统发育树,研究表明：菌株DX-A与Acidiphilium sp.PK46（AY765995）位于系统发育树的同一分支中,相似度为99%;菌株DX-A分别浸出黄铁矿和铁闪锌矿28 d后,含菌摇瓶中Fe2＋与Zn2＋的质量浓度分别可达到2.36g/L和2.47 g/L,而对照组中Fe2＋与Zn2＋的质量浓度分别为0.60 g/L和0.39 g/L;菌株DX-A和A.ferrooxidansATCC23270混菌分别浸出黄铁矿和铁闪锌矿比A.ferrooxidans ATCC23270单菌浸出效果分别高2.7%和10.3%,表明该菌能够浸出黄铁矿和铁闪锌矿并能促进自养菌的浸矿,为进一步研究异养菌促进自养菌浸矿提供了依据。

An Acidiphilium strain named DX-A was isolated from acid mine drainage of Dexing mine,Jiangxi Province,China.Strain DX-A is rod-shaped in（0.45 0.55） μm×（1.1 2.1） μm and Gram negative.The optimum temperature and pH for cultivation of DX-A are 30 ℃ and 3.5.FeCl3,and other kinds of sulfide ores and organics（such as glucose）,except FeSO4,can be utilized to help strain DX-A grow.Strain DX-A has the closest relativity to the Acidiphilium sp.PK46（AY765995）,with 99% sequence similarity based on the phylogenetic tree,which was constructed according to the published 16S rDNA gene sequences of the relative bacteria species.After cultivating strain DX-A in the flask respectively containing pyrite and marmatite for 28 d,the mass concentrations of the Fe2＋and Zn2＋ reach to 2.36 g/L and 2.47 g/L,respectively,while those of the controls are only 0.60 g/L and 0.39 g/L.After strain DX-A and A.ferrooxidans ATCC23270 together leached pyrite as well as marmatite,the mass concentrations of Fe2＋and Zn2＋are 2.7% and 10.3% respectively higher than only A.ferrooxidans ATCC23270 did.The results show that the strain can leach pyrite and marmatite and promote the leaching ability of autotrophic bacteria.All of these provide some evidences for further study on the promotion effects of bioleaching,which are caused by heterotrophic bacteria.