海洋细菌对DMSP的降解及其在极地低温海域的研究进展

DMSP(二甲基巯基丙酸内盐)是地球上最丰富的有机含硫化合物之一,同时也是海洋微生物的重要营养物。浮游植物是其主要的生产者。DMSP还是海洋中DMS(二甲基硫)的重要来源和前体,而DMS的排放与全球气候变化存在密切关联。细菌在DMSP的降解及DMS的生成方面扮演着重要角色。有关DMSP生物合成、代谢及其生态影响的研究已开展了近70年,但涉及高纬度极地低温海域的相关研究却为数甚少。本文在简要介绍DMSP生物合成与代谢,以及DMSP降解途径中的关键酶基因及其产生菌的基础上,结合笔者的工作实践,对近年来在极地低温海域的相关研究进行了介绍并展开了部分讨论。随着国内对微生物驱动水圈地球元素循环的重视,有关极地海域细菌参与DMSP/DMS代谢的研究工作将极大地增进人们对于微生物在极地海洋生态系统中生态地位的认识,也对评估极地海洋微生物群落对全球气候环境变化的响应与反馈具有重要的参考意义。

Bacterial catabolism of Dimethylsulfoniopropionate (DMSP) in polar marine areas

Dimethylsulfoniopropionate (DMSP) is one of the most abundant organosulfur compounds on Earth, and a key nutrient for marine microorganisms. The main producers of DMSP are phytoplankton. DMSP is also the major precursor for gaseous dimethyl sulfide (DMS), which is important in global sulfur cycling and potentially affects weather and climate. Bacteria play an important role in the processes of DMSP degradation and DMS production. The pathways of DMSP synthesis and metabolism and the ecological impacts of DMSP have been studied for nearly 70 years. However, most of those studies have been performed at low- and mid-latitudes, and few experiments have been conducted in cold waters at high latitudes. In this review, I briefly introduce DMSP synthesis and catabolism, and then summarize recent advances in research on genes involved in DMSP degradation and the organisms that harbor those genes in polar marine areas. Studies on the bacterial metabolism of DMSP/DMS in polar marine areas will greatly improve our understanding of the role of microorganisms in the polar marine ecosystem, and the responses and feedback of marine microbial communities in the polar region to global climate change.