Abstract
Cell extracts from the ciliate Tetrahymena thermophila catalyzed the S-adenosylmethionine-dependent methylation of sulfide. The product of the reaction, methanethiol, was detected by a radiometric assay and by a gas-chromatographic assay coupled to a sulfur-selective chemiluminescence detector. Extracts also catalyzed the methylation of selenide, and the product was shown by gas chromatography-mass spectrometry to be methaneselenol. The sulfide and selenide methyltransferase activities copurified with the aromatic thiol methyltransferase previously characterized from this organism (A.-M. Drotar and R. Fall, Pestic. Biochem. Physiol. 25:396-406, 1986), but heat inactivation experiments suggested the involvement of distinct sulfide and selenide methyltransferases. Short-term toxicity tests were carried out for sulfide, selenide, and their methylated derivatives; the monomethylated forms were somewhat more toxic than the nonmethylated or dimethylated compounds. Cell suspensions of T. thermophila exposed to sulfide, methanethiol, or their selenium analogs emitted methylated derivatives into the headspace. These results suggest that this freshwater protozoan is capable of the stepwise methylation of sulfide and selenide, leading to the release of volatile methylated sulfur or selenium gases.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Drotar A. M., Fall R. Microbial methylation of benzenethiols and release of methylthiobenzenes. Experientia. 1985 Jun 15;41(6):762–764. doi: 10.1007/BF02012585. [DOI] [PubMed] [Google Scholar]
- Drotar A., Burton G. A., Jr, Tavernier J. E., Fall R. Widespread occurrence of bacterial thiol methyltransferases and the biogenic emission of methylated sulfur gases. Appl Environ Microbiol. 1987 Jul;53(7):1626–1631. doi: 10.1128/aem.53.7.1626-1631.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Esaki N., Tanaka H., Uemura S., Suzuki T., Soda K. Catalytic action of L-methionine gamma-lyase on selenomethionine and selenols. Biochemistry. 1979 Feb 6;18(3):407–410. doi: 10.1021/bi00570a003. [DOI] [PubMed] [Google Scholar]
- Ganther H. E., Kraus R. J. Identification of hydrogen selenide and other volatile selenols by derivatization with 1-fluoro-2,4-dinitrobenzene. Anal Biochem. 1984 May 1;138(2):396–403. doi: 10.1016/0003-2697(84)90828-5. [DOI] [PubMed] [Google Scholar]
- Kadota H., Ishida Y. Production of volatile sulfur compounds by microorganisms. Annu Rev Microbiol. 1972;26:127–138. doi: 10.1146/annurev.mi.26.100172.001015. [DOI] [PubMed] [Google Scholar]
- Nashef A. S., Osuga D. T., Feeney R. E. Determination of hydrogen sulfide with 5,5'-dithiobis-(2-nitrobenzoic acid), N-ethylmaleimide, and parachloromercuribenzoate. Anal Biochem. 1977 May 1;79(1-2):394–405. doi: 10.1016/0003-2697(77)90413-4. [DOI] [PubMed] [Google Scholar]
- Segal W., Starkey R. L. Microbial decomposition of methionine and identity of the resulting sulfur products. J Bacteriol. 1969 Jun;98(3):908–913. doi: 10.1128/jb.98.3.908-913.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Weisiger R. A., Pinkus L. M., Jakoby W. B. Thiol S-methyltransferase: suggested role in detoxication of intestinal hydrogen sulfide. Biochem Pharmacol. 1980 Oct 15;29(20):2885–2887. doi: 10.1016/0006-2952(80)90029-5. [DOI] [PubMed] [Google Scholar]
- Zinder S. H., Doemel W. N., Brock T. D. Production of volatile sulfur compounds during the decomposition of algal mats. Appl Environ Microbiol. 1977 Dec;34(6):859–860. doi: 10.1128/aem.34.6.859-860.1977. [DOI] [PMC free article] [PubMed] [Google Scholar]