六价铬还原细菌Bacillus cereus S5.4的筛选鉴定及还原特性研究  

Isolation,identification and hexavalent chromium reduction studies of Bacillus cereus S5.4

作　　者：肖伟[1] 王磊[2] 张思维[1] 乔文杰[1] 付小花[1] 任大明[1] 

机构地区：[1]复旦大学遗传工程国家重点实验室,上海200433 [2]同济大学环境科学与工程学院,上海200092

出　　处：《工业微生物》2007年第6期1-6,共6页Industrial Microbiology

基　　金：国家自然科学基金项目(40571145)

摘　　要：六价铬生物毒性极大，是造成环境污染的主要重金属之一，其生物治理策略已引起了广泛关注。已经发现许多微生物具有六价铬抗性和还原性，但能工业应用的还十分有限。从宝钢电镀污泥中分离得到一系列高六价铬抗性菌株，其中一株S5．4显示出高六价铬还原性，经形态和生理生化特征及16s rDNA序列比对，鉴定为Bacillus cereus。该菌株好氧生长，在固体LB培养基上培养48h能耐受40mmol／L Cr^6＋，并对Mn^2＋、Ba^2＋和Mo^6＋也显出高抗性；在液体LB培养基中培养72h完全还原2mmol／L Cr^6＋，并能在补充培养基和六价铬的条件下连续还原。该菌株还原六价铬时，最适浓度为2mmol／L Cr^6＋，最适温度范围30～37℃，最适pH7～9。Hexavalent chromium, regarded as one of the most dangerous pollutants among heavy metals in the environment for its toxicity to living organisms, is being widely studied for its bioremediation. More and more microorganisms showing steady resistance and reduction ability of hexavalent chromium were identified, but few of them were applied to industrial fields. A series of bacteria with high resistance of hexavalent chromium were isolated from the electroplating sludge of Baosteel Corporation, Shanghai. A strain named S5.4, which showed high reduction ability of hexavalent chromium, was identified as Bacillus cereus by morphological, physiological and biochemical characteristics and its 16s rDNA sequence. Under the aerobic conditions, this strain was able to grow on LB plates with 40mmol/L Cr^6＋ after 48h, and also showed high endurance on Mn^2＋ , Ba^2＋ and Mo^6＋. At the same time, this strain was able to completely reduce 2 mmol/L Cr^6＋ in LB liquid after 72 h, and work continuously with supplement of cultural medium and hexavalent chromium. For reducing hexavalent chromium, the optimal concentration, temperature range and pH range were 2mmol/L Cr^6＋, 30-37℃ and pH 7-9, respectively.

关 键 词：BACILLUS CEREUS 六价铬抗性 六价铬还原性 微生物鉴定 

分 类 号：X505[环境科学与工程—环境工程]