A mechanism for bacterial transformation of dimethylsulfide to dimethylsulfoxide: a missing link in the marine organic sulfur cycle

作者：Lidbury, Ian; Krober, Eileen; Zhang, Zhidong; Zhu, Yijun; Murrell, J. Colin; Chen, Yin^*; Schafer, Hendrik^*

来源：Environmental Microbiology, 2016, 18(8): 2754-2766.

DOI：10.1111/1462-2920.13354

• TRIMETHYLAMINE-N-OXIDE
• FLAVIN-CONTAINING MONOOXYGENASE
• COMMUNITY STRUCTURE
• ANTISENSE RNA
• SARGASSO SEA
• OCEANIC PHYTOPLANKTON
• COMPARATIVE GENOMICS
• MOLECULAR ANALYSIS
• ROSEOBACTER-CLADE
• GENE-EXPRESSION

The volatile organosulfur compound, dimethylsulfide (DMS), plays an important role in climate regulation and global sulfur biogeochemical cycles. Microbial oxidation of DMS to dimethylsulfoxide (DMSO) represents a major sink of DMS in surface seawater, yet the underlying molecular mechanisms and key microbial taxa involved are not known. Here, we reveal that Ruegeria pomeroyi, a model marine heterotrophic bacterium, can oxidize DMS to DMSO using trimethylamine monooxygenase (Tmm). Purified Tmm oxidizes DMS to DMSO at a 1:1 ratio. Mutagenesis of the tmm gene in R. pomeroyi completely abolished DMS oxidation and subsequent DMSO formation. Expression of Tmm and DMS oxidation in R. pomeroyi is methylamine-dependent and regulated at the post-transcriptional level. Considering that Tmm is present in approximately 20% of bacterial cells inhabiting marine surface waters, particularly the marine Roseobacter clade and the SAR11 clade, our observations contribute to a mechanistic understanding of biological DMSO production in surface seawater.

• 出版日期2016-8
• 单位新疆农业科学院