一株甲胺磷高效降解菌——巨大芽孢杆菌(Bacillus megaterium)的分离及其分子鉴定

湘潭南天化工厂的甲胺磷废水未经处理直接排放,对湘江及下游的湖泊造成了一定的污染,利用解磷微生物去除江河湖泊中的甲胺磷污染是一条有效的途径.本文作者从被该厂甲胺磷废水污染的湖泊中分离细菌样品,以甲胺磷为唯一碳源和能源,经过定向筛选,得到一株可高效降解甲胺磷的菌株HN001.气相色谱测定结果表明,此菌株对甲胺磷的降解率在48h和96h分别为49.24%和98.20%.对其进行了常规生理生化测试,结果表明,该菌株与巨大芽孢杆菌的表型特征非常相似.为了进一步确定HN001的分类学地位,测定了其16S rRNA基因序列,分析了相关细菌相应序列的同源性,构建了分子系统发生树,结果表明菌株HN001与巨大芽孢杆菌的亲缘关系最近.综合上述结果,菌株HN001可鉴定为巨大芽孢杆菌(Bacillus megaterium).

BACILLUS MEGATERIUM, AN EFFICIENT BIODEGRADER TO METHAMIDOPHOS: ISOLATION AND MOLECULAR IDENTIFICATION

A bacteria strain HN001 showing efficient biodegrading ability to methamidophos was isolated and purified from methamidophos-polluted sludge from a local chemical factory discharge in Hunan Province. The methamidophos-degrading rate of this strain determined in gas-chromatography reached 49.24% and 98.20% in 48h and 96h, respectively. The strain is very similar to Bacillus megaterium in most of the phenotypes in traditional physiological and biochemical aspects, as well as in molecular phylogenetic dendrogram built from 1515bp 16S rRNA gene sequence with which those of related strains were compared. Therefore, strain HN001 was identified as B. megaterium.