When DMS is released into the atmosphere, DMS oxidation products help form clouds which reflect sunlight away from the Earth, effectively cooling the planet. This natural process is essential for regulating the Earth's climate and is also hugely important for the global sulfur cycle, representing the main route by which sulfur from the oceans is returned to land.
UEA and OUC established the Sino-UK Joint Research Centre to promote cutting-edge research and teaching in marine and ocean science. UEA's Dr. Andrew Curson was a key member of the team that identified the novel enzymes responsible for the synthesis of DMSP in diverse bacteria, photosynthetic cyanobacteria and algae. Dr. Curson said, "The identity of these enzymes allowed our team to identify Pelagophyceae as potentially abundant and important DMSP producers."
Co-lead author Professor Xiao-Hua Zhang, of OUC's College of Marine Life Science, added, "By identifying the enzymes involved in DMSP production, scientists can better understand and predict the behavior of these ecosystem-disruptive, brown-tide-forming algae and their impact on global climate change. This study has also raised questions about other unidentified versions of the enzymes needed to make DMSP, or entirely different pathways for making it that are currently unknown."
The researchers say further study of Pelagophyceae algae in their natural environment is needed, as well as more detailed studies on other marine organisms. Better measurements of environmental DMSP levels, production and breakdown rates, and the abundance of the enzymes involved in making DMSP are also critical to further advance the field.
The research was a collaboration between UEA and OUC, with contributions from Qingdao Agricultural University, the University of Porto, Shandong University and the Laoshan Laboratory in Qingdao, China.
Source: Phys.Org
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RESEARCH PAPER—Alternative dimethylsulfoniopropionate biosynthesis enzymes in diverse and abundant microorganisms
Authors
Jinyan Wang, Andrew R. J. Curson, Shun Zhou, Ornella Carrión, Ji Liu, Ana R. Vieira, Keanu S. Walsham, Serena Monaco, Chun-Yang Li, Qing-Yu Dong, Yu Wang, Peter Paolo L. Rivera, Xiao-Di Wang, Min Zhang, Libby Hanwell, Matthew Wallace, Xiao-Yu Zhu, Pedro N. Leão, David J. Lea-Smith, Yu-Zhong Zhang, Xiao-Hua Zhang & Jonathan D. Todd
11 June 2024
Abstract
Dimethylsulfoniopropionate (DMSP) is an abundant marine organosulfur compound with roles in stress protection, chemotaxis, nutrient and sulfur cycling and climate regulation. Here we report the discovery of a bifunctional DMSP biosynthesis enzyme, DsyGD, in the transamination pathway of the rhizobacterium Gynuella sunshinyii and some filamentous cyanobacteria not previously known to produce DMSP. DsyGD produces DMSP through its N-terminal DsyG methylthiohydroxybutyrate S-methyltransferase and C-terminal DsyD dimethylsulfoniohydroxybutyrate decarboxylase domains. Phylogenetically distinct DsyG-like proteins, termed DSYE, with methylthiohydroxybutyrate S-methyltransferase activity were found in diverse and environmentally abundant algae, comprising a mix of low, high and previously unknown DMSP producers. Algae containing DSYE, particularly bloom-forming Pelagophyceae species, were globally more abundant DMSP producers than those with previously described DMSP synthesis genes. This work greatly increases the number and diversity of predicted DMSP-producing organisms and highlights the importance of Pelagophyceae and other DSYE-containing algae in global DMSP production and sulfur cycling.
Overview of key DMSP biosynthesis enzymes and pathways and their environmental importance.Source: Nature Microbiology