Breakdown of dimethyl sulphide by mixed cultures and by Thiobacillus thioparus

✍ Scribed by Takahiro Kanagawa; D.P. Kelly

• Book ID: 109313249
• Publisher: John Wiley and Sons
• Year: 1986
• Tongue: English
• Weight: 514 KB
• Volume: 34
• Category: Article
• ISSN: 0378-1097
• DOI: 10.1111/j.1574-6968.1986.tb01340.x

✦ Synopsis

Dimethyl sulphide (DMS) was degraded by acclimatized activated sludge and by a mixed culture of Thiobacillus thioparus TK-1 and Pseudomonas sp. AK-2. While both these organisms persisted in stable co-culture on DMS, it was found that T. thioparus TK-1 and the derived strain TK-m grew in pure culture on DMS, and oxidized DMS with an apparent K m of 4.5 × 10 -5 M. During growth, all the DMS-sulphur was oxidized stoichiometrically to sulphate but no methanol was detected in pure cultures of TK-m. DMScarbon was probably converted to CO 2, since the fixation of ~4CO 2 was progressively diluted during growth of a culture on ~4CO2 and DMS. Growth yields were consistent with autotrophic growth, dependent on the oxidation of the methyl residues to CO 2 (probably with formaldehyde as a first intermediate) and the sulphide to sulphate. The organism thus appears to exhibit a mixture, from the one substrate, of chemolithotrophic and meth-