MOE Key Laboratory of Evolution and Marine Biodiversity, Frontiers Science Center for Deep Ocean Multispheres and Earth System & College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China.
Key Laboratory on Agricultural Microorganism Resources Development of Shangqiu, Shangqiu Normal University, Shangqiu 476000, China.
Mar Genomics. 2024 Aug;76:101112. doi: 10.1016/j.margen.2024.101112. Epub 2024 May 7.
Dimethylsulfoniopropionate (DMSP) is a ubiquitous organosulfur molecule in marine environments with important roles in stress tolerance, global carbon and sulfur cycling, and chemotaxis. It is the main precursor of the climate active gas dimethyl sulfide (DMS), which is the greatest natural source of bio‑sulfur transferred from ocean to atmosphere. Alteromonas sp. M12, a Gram-negative and aerobic bacterium, was isolated from the seawater samples collected from the Mariana Trench at the depth of 2500 m. Here, we report the complete genome sequence of strain M12 and its genomic characteristics to import and utilize DMSP. The genome of strain M12 contains one circular chromosome (5,012,782 bp) with the GC content of 40.88%. Alteromonas sp. M12 can grow with DMSP as a sole carbon source, and produced DMS with DMSP as a precursor. Genomic analysis showed that strain M12 contained a set of genes involved in the downstream steps of DMSP cleavage, but no known genes encoding DMSP transporters or DMSP lyases. The results indicated that this strain contained novel DMSP transport and cleavage genes in its genome which warrants further investigation. The import of DMSP into cells may be a strategy of strain M12 to adapt the hydrostatic pressure environment in the Mariana Trench, as DMSP can be used as a hydrostatic pressure protectant. This study sheds light on the catabolism of DMSP by deep-sea bacteria.
二甲基巯基丙酸酯 (DMSP) 是海洋环境中普遍存在的有机硫分子，在应激耐受、全球碳和硫循环以及趋化作用中具有重要作用。它是气候活性气体二甲基硫 (DMS) 的主要前体，是生物硫从海洋转移到大气的最大自然来源。从马里亚纳海沟 2500 米深的海水样本中分离到革兰氏阴性需氧细菌 Altermomonas sp. M12。在这里，我们报告了菌株 M12 的完整基因组序列及其基因组特征，以导入和利用 DMSP。菌株 M12 的基因组包含一个环状染色体（5,012,782 bp），GC 含量为 40.88%。Altermomonas sp. M12 可以 DMSP 作为唯一碳源生长，并以 DMSP 为前体产生 DMS。基因组分析表明，菌株 M12 含有一套参与 DMSP 裂解下游步骤的基因，但没有编码 DMSP 转运蛋白或 DMSP 裂解酶的已知基因。结果表明，该菌株的基因组中含有新型的 DMSP 转运和裂解基因，值得进一步研究。DMSP 进入细胞可能是菌株 M12 适应马里亚纳海沟静压环境的一种策略，因为 DMSP 可用作静压保护剂。本研究揭示了深海细菌对 DMSP 的分解代谢。
