Similar but different: characterization of dddD gene mediated dimethylsulfoniopropionatemetabolism among Coral-Associated Endozoicomonas

Abstract

Endozoicomonas, the predominant bacterium associated with corals, is believed to play crucial roles in maintaining coral health. Its role in dimethylsulfoniopropionate (DMSP) degradation has been a subject of discussion for over a decade. A previous study found Endozoicomonas degraded DMSP through dddD pathway. This process releases dimethyl sulfide (DMS), which is vital for corals coping with thermal stress. However, little is known about the related gene regulation and metabolic abilities of DMSP metabolism in Endozoicomonadaceae. In this study, we observed a distinct DMSP metabolic trend in two phylogenetically close dddD -harboring Endozoicomonas species confirming genetically by the comparative transcriptomic profiling and visualizing the change of DMSP stable isotopes in bacterial cell using NanoSIMS. Furthermore, we found that DMSP cleavage enzymes are ubiquitous in coral Endozoicomonas with a preference for possessing DddD lyase. We speculate harboring DMSP degrading genes enables Endozoicomonas to successfully colonize various coral species across the globe. Teaser: Coral-associated Endozoicomonas are widespread DMSP degraders monopolized by the dddD gene, employing various degradation mechanisms.