Degradation of dimethyl disulfide by Pseudomonas fluorescens strain 76

Strain 76, which was able to utilize dimethyl disulfide (DMDS) as a sole sulfur source, was screened from our microbial collection. It was identified as Pseudomonas fluorescens by taxonomical characterization and 16S rDNA sequence analysis. It does not belong to the methylotrophs, because it did not grow on DMDS or other C1 compounds as sole carbon source, and DMDS degradation was not repressed in the presence of glucose, Na2SO4, or nutrient broth. Moreover, it showed high resistance to DMDS by growing in DMDS at concentrations up to 9.04 mM. Based on these findings, strain 76 metabolizes DMDS and has dual physiological roles: sulfur assimilation and degradation. Thus it has advantages as a biological scavenger of DMDS.