摘要
从山东崅屿采集的黄棕壤中分离得到一株具有抗Mn(Ⅱ)和Mn(Ⅱ)氧化双重活性的芽胞杆菌,其最高Mn(Ⅱ)耐受浓度达到130mmol/L,对Mn(Ⅱ)的氧化活性为3.3μmol/(L·d)。通过个体形态与培养特征观测、生理生化反应、G+Cmol%测定和16SrDNA序列比对分析等鉴定,确定该菌株为巨大芽胞杆菌(Bacillus megaterium),命名为MB283。该菌株在添加Mn(Ⅱ)(10mmol/L)条件下比不添加Mn(Ⅱ)表现出相对较快的生长速率。采用高温培养并结合0.01%SDS处理,从MB283菌株筛选到一株发生内生质粒消除的突变株MB287,具有与野生菌株类似的锰耐受活性,且对Mn(Ⅱ)的氧化活性与野生菌株相比无明显改变,表明野生菌株MB283中与锰抗性和锰氧化相关的基因可能是定位于该菌的染色体上。
A bacilli-shaped isolate with a unique dual manganese（Ⅱ）-resistant and manganese（Ⅱ）-oxidizing activities was screened from the yellow brown soil samples that collected in Queyu,Shandong Province,China.It exhibited a maximum manganese-resistant activity by 130 mmol/L of Mn（Ⅱ）,and a maximum manganese-oxidizing activity by 3.3 μmol/（L·d）.This isolated was identified as a Bacillus megaterium strain（named as MB283） according to the morphological,physiological and biochemical characteristics,G ＋ C content as well as the 16S rDNA sequence alignment analyses.Interestingly,the cell growth of MB283 was favored by the low concentration Mn（Ⅱ）（10 mmol/L）.A plasmid-cured mutant strain named as MB287 was obtained by perseveringly incubation of the strain at 43℃ and supplementing additionally with 0.01% SDS.It was found that this mutant strain exhibited the proximate Mn（Ⅱ）-resistant and Mn（Ⅱ）-oxidizing activities compared to its wild-type strain.Thus,the results indicated that the corresponding genes of manganese resistance/oxidation in MB283 could locate in its chromosomal DNA.
出处
《微生物学通报》
CAS
CSCD
北大核心
2010年第9期1287-1292,共6页
Microbiology China
基金
国家自然科学基金项目(No40830527)
关键词
锰抗性
巨大芽胞杆菌
锰氧化
鉴定
质粒消除
Manganese resistance
Bacillus megaterium
Manganese oxidation
Identification
Plasmid curing
