遗传 ›› 2005, Vol. 27 ›› Issue (5): 787-791.

• 研究报告 • 上一篇    下一篇

嗜酸氧化亚铁硫杆菌亚铁氧化酶基因分子多态性研究

杨宇;彭宏;孙斌;王杰伟;胡岳华   

  1. 中南大学资源加工与生物工程学院,长沙 410083
  • 收稿日期:2004-11-22 修回日期:2005-02-17 出版日期:2005-10-10 发布日期:2005-10-10
  • 通讯作者: 胡岳华

Molecular Diversity of the Gene Encoding Fe(II)-oxidizing Enzyme in Acidithiobacillus ferrooxidans

YANG Yu, PENG Hong , SUN Bin ,WANG Jie-Wei , HU Yue-Hua   

  1. School of Resources Processing and Bioengineering , Central South University, Changsha 410083, China
  • Received:2004-11-22 Revised:2005-02-17 Online:2005-10-10 Published:2005-10-10

摘要: 嗜酸氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans, A.f)属于化能自养、革兰氏阴性细菌,好氧嗜酸,以氧化亚铁离子或还原态硫化物(S0&S2-)获得能量生长。在其Fe2+氧化系统中,亚铁氧化酶起重要作用。对不同硫化矿区分离得到的5株A.f进行生长动力学和对亚铁氧化活性的对比研究,结果显示不同菌株之间存在表型差异。提取A.f菌株的基因组DNA,设计引物,对亚铁氧化酶基因进行PCR扩增,同时对扩增产物直接进行测序,并同GenBank的参考序列进行比对分析,发现序列相似性在99%~97%之间,分析编码区域发现在第187~195位可能存在一个高变异区:在第187~189位,菌株YTW编码的氨基酸Thr→Pro;而在第193~195位,菌株TK是Met→Asn; 菌株BY则是Met→Ile。另外在位点第219位,所有菌株都是T→C,但编码的氨基酸未发生变化,属于同义密码子。对于编码区上游序列,比对后没有差异;而对于编码区下游序列,经比对发现存在一些差异位点。

关键词: 亚铁氧化酶基因, 嗜酸氧化亚铁硫杆菌, 分子多态性

Abstract: Acidithiobacillus ferrooxidans (A.f) is a Gram-negative chemolithotrophic bacterium able to oxidize ferrous iron, elemental sulfur and inorganic sulfur compounds. Fe(II)-oxidizing enzyme plays key role in Fe(II)-oxidizing system. Different A.f strains, which were isolated and purified from various ecological niches, show obviously phenotypic diversity after comparison rates of growth and oxidation of Fe2+ . The Fe(II)-oxidizing enzyme gene(iro) for five strains was identified by PCR reactions uitilising primers and genomic DNA, then sequenced and multialignment. The results show there is a putative high variable region in CDS between the 187th and 195th bp and the sequence similarities are from 97% to 99%. For strain YTW, P187~189 Thr→Pro; For P193~195, Met→Asn for strain TK; Met→Ile for strain BY ; For P219 , all strains T→C. For upstream of CDS , sequences of all strains are identical to the Genebank sequence (E03451), but downstream of CDS, the sequences exist some variable sites too.

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