北极近岸海域DMSP代谢细菌及相关基因的多样性及其生态地位分析

项目名称： 北极近岸海域DMSP代谢细菌及相关基因的多样性及其生态地位分析

项目编号： No.41476171

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 海洋科学

项目作者： 曾胤新

作者单位： 中国极地研究中心

项目金额： 88万元

中文摘要： DMSP是由海洋浮游植物及大型海藻产生、作为胞内渗透压调节剂的含硫化合物。它是全球硫、碳循环的重要参与者。海洋中的DMSP可被细菌通过脱甲基与裂解这两条主要的代谢途径利用，从而决定硫元素是以含硫蛋白的形式进入微生物食物网、还是以DMS的形式被释放并进入大气。大气中的DMS对于海洋乃至全球气候具有潜在的重要影响。有关细菌介导DMSP代谢的研究近年来已经成为海洋生态学研究领域的热点之一，但在极地低温海域中的相关工作却很少被报道。采用分离培养技术与分子生物学技术相结合的方法，通过对北极王湾海水中DMSP代谢细菌及相关功能基因多样性的研究，结合浮游细菌群落组成、环境参数、功能基因表达、以及南极近岸海域的相关结果等信息，不但可以增进我们对于浮游细菌参与极地低温海洋生态系统硫循环的认识，而且在了解极地海洋细菌的生物地理分布、极地海洋浮游细菌群落对全球气候变化的响应与反馈等方面具有重要的参考意义。

中文关键词： 浮游细菌；二甲基巯基丙酸内盐；多样性；生态功能；北极

英文摘要： As an organic sulfur compound for use as an osmolyte, the compatible solute dimethylsulfoniopropionate (DMSP) is produced worldwide, mainly by marine phytoplankton and macroalgae. This compound is a major participant in the global sulfur and carbon cycles. When released into seawater, DMSP is rapidly metabolized by marine bacteria via two major pathways. These two competing pathways may play a role in determining the balance between the incorporation of sulfur into the marine microbial food web (the demethylation pathway) and the release of sulfur in the form of the climate-influencing gas dimethyl sulfide (DMS; the cleavage pathway). DMS represents a major source of biogenic sulfur to the atmosphere and has the potential to exert major cooling effects on climate. Although in recent years insights into bacterial DMSP metabolism have provided an improved understanding of biogeochemical cycling of sulfur in marine ecosystems, knowledges about bacteria and their genes involved in DMSP metabolism in cold marine ecosystem in polar regions are still limited to us. By a combination of culture-dependent and independent approaches, studies will be performed to investigate the diversity of planktonic bacteria and their genes involved in DMSP metabolism in Arctic Kongsfjorden, combined with informations of bacterioplankton community composition, environment properties, expression of bacterial DMSP degradation genes and even comparison between Arctic and Antarctic coastal samples. Those results will be helpful to improve our knowledge about the ecological role of DMSP-metabolizing bacteria in Arctic cold marine environment, biogeographic distribution of bacteria between Arctic and Antarctic seawaters, and the response and feedback of bacterioplankton community in polar marine environments to global climate change.

英文关键词： Bacterioplankton;DMSP;Diversity;Ecological function;Arctic