南大西洋深海热液区可培养硫氧化微生物多样性及其硫氧化特性

Diversity of culturable sulfur-oxidizing bacteria in deep-sea hydrothermal vent environments of the South Atlantic

摘要:

【目的】探索南大西洋热液环境中的硫氧化细菌多样性并研究其硫氧化特性。【方法】通过富集培养和分离纯化获得硫氧化细菌,利用变性梯度凝胶电泳(DGGE)分析富集菌群组成结构,采用离子色谱法对获得的硫氧化细菌硫氧化特性进行检测。【结果】从南大西洋深海环境样品中共分离到48株菌,分属于alpha-Proteobacteria(28株, 58.3%)、Actinobacteria(11株, 22.9%)和gama-Proteobacteria(9株,18.8%)共3个门,其中Thalassospira、Martelella和Microbacterium为优势属。DGGE结果表明深海热液环境样品中微生物多样性丰富且不同站位存在差异。硫氧化特性研究结果表明,约60%的分离菌株具有硫氧化能力,可以氧化S₂O₃^2-生成SO₄^2-。获得一株硫氧化能力较强的潜在新种L6M1-5,在实验条件下可高效氧化S₂O₃^2-,最大氧化速率可达0.56 mmol/(L·h)。【结论】南大西洋深海热液环境中可培养硫氧化细菌多样性丰富,为研究热液环境中的硫循环过程提供了实验材料和理论参考;同时高效硫氧化菌的获得,为工业化含硫废水的处理提供了良好的菌种资源。

Abstract:

[Objective] To investigate the diversity of culturable sulfur-oxidizing bacteria in hydrothermal vent environments of the South Atlantic, and analyze their characteristics of sulfur oxidation.[Methods] We enriched and isolated sulfur-oxidizing bacteria from hydrothermal vent samples collected from the South Atlantic. The microbial diversity in enrichment cultures was analyzed using the Denatural Gradient Gel Electrophoresis method. Sulfur-oxidizing characteristics of the isolates was further studied by using ion chromatography.[Results] A total of 48 isolates were obtained from the deep-sea hydrothermal vent samples, which belonged to 23 genera and mainly grouped into alphaProteobacteria(58.3%), Actinobacteria(22.9%) and gama-Proteobacteria(18.8%). Among them, the genus Thalassospira, Martelella and Microbacterium were dominant. About 60% of the isolates exibited sulfur-oxidizing ability and strain L6M1-5 had a higher sulfur oxidation rate by comparison analysis.[Conclusion] The diversity of sulfur-oxidizing bacteria in hydrothermal environments of the South Atlantic was reported for the first time based on culture-dependent methods. The result will help understand the biogechemical process of sulfur compounds in the deep-sea hydrothermal environments.