中国东海和南海海域可培养烃类降解细菌的筛选及功能

Screening and characterization of culturable hydrocarbon-degrading strains from the South and East China Seas

摘要:

【背景】海洋环境中蕴藏着丰富的微生物资源，其种类繁多而且功能多样，在驱动物质循环及能量流动等方面起着重要的作用。目前，海洋中烷烃化合物降解菌的分离筛选和降解功能研究已有文献报道；但是对海洋中尤其是我国东海和南海海域，具有降解芳香烃类化合物功能的菌株分离筛选及其多样性研究鲜有报道。【目的】分离筛选我国东海和南海海域具有烃类降解能力的可培养菌株，并对其降解功能和多样性进行初步研究。【方法】分别从东海和南海海底沉积物样品中筛选菌株，选择不同的烃类化合物为菌株筛选的唯一碳源，采用梯度稀释和平板划线法分离纯化得到单菌落，并利用相应烃类为唯一碳源进行生长验证获得该化合物降解菌。【结果】以肉桂酸、碱木素、十六烷等12种烃类化合物为唯一碳源，从样品中共分离到63株具有烃类化合物降解能力的菌株，分别属于3个门4个纲8个目10个属，主要为红球菌属(Rhodococcus)、不动杆菌属(Acinetobacter)、弧菌属(Vibrio)、盐单胞菌属(Halomonas)、假单胞菌属(Pseudomonas)。两大海域优势降解菌差别较大，其中东海沉积物降解菌株主要为不动杆菌属(Acinetobacter)，而南海沉积物降解菌株主要为红球菌属(Rhodococcus)。【结论】我国东海和南海海域蕴藏着丰富的烃类化合物降解菌株资源，两大海域优势降解菌种类存在明显差异，这将为我国未来可能的海洋环境石油污染的微生物治理储备菌种资源。

Abstract:

[Background] Abundant microbial resources exist in the sea with various species and functions, playing important roles in driving substance circulation and energy flow. Screening and studying the diversity of marine strains capable of degrading hydrocarbons can be important for this purpose, especially in the South and East China Seas where this resource is still underexplored. [Objective] We screened culturable strains with hydrocarbon degradation ability, and studied their diversity and function to degrade hydrocarbons. [Methods] The sediment samples were collected from the South and East China Seas. Different hydrocarbons were used as the sole carbon source to isolate bacterial strains by serial dilution and plate streaking procedures. Then the growth of the isolated strains was investigated using corresponding hydrocarbon compounds as the sole source of carbon and energy. [Results] From the samples used, 63 strains with the ability to degrade hydrocarbon compounds were isolated, belonging to 3 phyla, 4 classes, 8 orders, and 10 genera. They are mainly Rhodococcus, Acinetobacter, Vibrio, Halomonas, Pseudomonas. The degrading strains from sediments in the East China Sea were mainly Acinetobacter, whereas those from the South China Sea were mainly Rhodococcus, exhibiting differences in major genera of degrading strains between the two areas. [Conclusion] Hydrocarbon-degrading strains from the South and East China Seas have the potential bioremediation of petroleum-polluted marine environments.