Characterization of three novel dimethyl disulfide degrading bacteria and their potential degradation pathways

Dimethyl disulfide (DMDS) is an odor compound characterized by the lowest olfactory threshold and high toxicity. It is indispensable to explore the bacteria with high resistance and degradation efficiency to DMDS. Acinetobacter lwoffii, Pseudomonas mendocina, and Myroides odoratus were isolated from kitchen waste. After 6 days of individual treatment, the removal rates were 34.22 %, 40.95 %, and 41.94 % respectively. The DMDS metabolic pathways based on metagenomic assays were discovered to be incomplete due to the insufficient annotation of some key genes in the current database. Following 3 days of treatment with bacterial consortia at ratios of 5:1 for A. lwoffii C2/ M. odoratus C7 and 1:1:1 for the three strains achieved 100 % DMDS removal. Additionally, the consortia reduced hydrogen sulfide (H2S) and dimethyl sulfide (DMS). This discovery broadens the spectrum of bacteria exhibiting high tolerance and efficient degradation of DMDS, with significant implications for DMDS removal and odor treatment.