Thiol methylation potential in anoxic, low-pH wetland sediments and its relationship with dimethylsulfide production and organic carbon cycling
✍ Scribed by Edward G Stets; Mark E Hines; Ronald P Kiene
- Book ID
- 104307958
- Publisher
- John Wiley and Sons
- Year
- 2004
- Tongue
- English
- Weight
- 482 KB
- Volume
- 47
- Category
- Article
- ISSN
- 0168-6496
No coin nor oath required. For personal study only.
✦ Synopsis
Dimethylsulfide (CH(3)SCH(3)) is formed in anoxic freshwater sediments by biological methylation of methanethiol (CH(3)SH). We measured thiol methylation potential in low-pH, Sphagnum peat sediments from Alaska and Alabama by adding ethanethiol (CH(3)CH(2)SH) to peat slurries and quantifying the rate of ethylmethylsulfide (CH(3)CH(2)SCH(3)) formation. Thiol methylation potential ranged from 12 to 154 nM h(-1) and was significantly related to dimethylsulfide accumulation rates (P=0.0007; r(2)=0.48). Addition of methanol or syringic acid stimulated thiol methylation potential and dimethylsulfide accumulation rate, suggesting that these compounds could be methyl donors. Addition of acetate or its metabolic precursors (glucose or Sphagnum plant material) inhibited thiol methylation potential, but not carbon dioxide or methane production. Inhibition of methanogenesis with either 2-bromoethanesulfonic acid or KNO(3) consistently inhibited thiol methylation potential and dimethylsulfide accumulation. These results suggest that methanogens play a role in thiol methylation and therefore dimethylsulfide formation.