Structural and Regulatory Genes Required to Make the Gas Dimethyl Sulfide in Bacteria | Semantic Scholar (2024)

The global distribution pattern of DMSP and DMS, the known genes for biosynthesis and cleavage ofDMSP, and the physiological and ecological functions of these important organosulfur molecules are described, which will improve understanding of the mechanisms of DM SP and D MS production and their roles in the environment.

AcoD, an ATP-dependent DMSP lyase that belongs to the acyl-CoA synthetase superfamily, is widely distributed in many bacterial lineages, revealing this new pathway plays important roles in global DMSP/DMS cycles.

The crystal structure of DddQ, a DMSP lyase, was solved, and detailed biochemical and structural analyses were performed, providing important insight into the mechanism involved in the conversion of DMSP into DMS, which should lead to a better understanding of this globally important biogeochemical reaction.

Genomic and functional genomic methods applied to both model organisms and natural communities have rapidly advanced understanding of bacterial dimethylsulfoniopropionate (DMSP) degradation in the ocean, but gene transcription analyses of natural bacterioplankton communities are making headway in unraveling the intricacies of bacterial DMSP processing in the Ocean.

Gene probes to the DMSP demethylation gene dmdA and theDMSP lyase gene dddP demonstrated that these DMSP-degrading genes are abundant and widely distributed in ECS seawaters, further confirming the link between this abundant bacterial class and the environmental DMSP cycling.

Experimental evidence is covered supporting the hypothesis that, as DMSP became more readily available in the marine environment, marine bacteria adapted enzymes already encoded in their genomes to utilize this new compound.

Comparative kinetic assays revealed differences in the conversion of DMSP and its analogues in terms of selectivity and overall velocity, giving additional insights into the molecular mechanisms ofDMSP lyases and into their putatively different biological functions.

This work has identified DMSP and acetyl-coenzyme A to be DddD's native substrates and Asp602 as the active site residue mediating the CoA-transferase prior to lyase activity and shed light on the biochemical utilization of DMSP in the marine environment.

DddX is a novel ATP-dependent DMSP lyase that belongs to the acyl-CoA synthetase superfamily and is distinct from the eight other knownDMSP lyases, and may play an overlooked role in DMSP/DMS cycles.

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Through the discovery of a glycine cleavage T-family protein with DMSP methyltransferase activity, marine bacterioplankton in the Roseobacter and SAR11 taxa were identified as primary mediators of DMSP demethylation to methylmercaptopropate.

Bacterial population analysis based on culturability has its limitations, bacteria from the α and γ subclasses of the Proteobacteria were the dominant DMS producers isolated from salt marsh sediments and estuaries, with the γ subclass representing 80% of the isolates.

This article is more comprehensive, as it includes some of the earlier literature in describing the sources of DMSP, its release and linkage to the marine (primarily microbial) food web and subsequent degradation via cleavage to DMS and acrylic acid or demethylation and demethiolation to methanethiol.

The results illustrate the significant potential for microbial conversion of dissolved DMSP to DMS in coastal seawater and the sensitivity to inhibitors with respect to growth and DMSP-lyase activity varied from strain to strain.

The diverse metabolism of DMSP by the dinoflagellate-associated Roseobacter spp.

The genome sequence of Silicibacter pomeroyi, a member of the marine Roseobacter clade, is described, indicating that this organism relies upon a lithoheterotrophic strategy that uses inorganic compounds to supplement heterotrophy.

A putative model is presented that best fits the experimental data regarding the pathway of DMSP and acrylate metabolism in the α-proteobacterium, strain LFR.

It is demonstrated that copepods can detect and react to plumes of DMS and suggest that this biogenic trace gas can influence the structure and function of pelagic foodwebs.

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