ANAEROBIC DEGRADATION OF DIMETHYLSULFONIOPROPIONATE TO 3-S-METHYLMERCAPTOPROPIONATE BY A MARINE DESULFOBACTERIUM STRAIN

Dimethylsulfoniopropionate, an osmolyte of marine algae, is thought to be the major precursor of dimethyl sulfide, which plays a dominant ro le in biogenic sulfur emission. The marine sulfate-reducing bacterium Desulfobacterium strain PM4 was found to degrade dimethylsulfoniopropi onate to 3-S-methylmercaptopropionate. The oxidation of one of the met hyl groups of dimethylsulfoniopropionate was coupled to the reduction of sulfate; this process is similar to the degradation of betaine to d imethylglycine which was described earlier for the same strain. Desulf obacterium PM4 is the first example of an anaerobic marine bacterium t hat is able to demethylate dimethylsulfoniopropionate.