Open AccessProperties of a soluble thiosulfate sulfur transferase (rhodanese) of the marine methanogen Methanosarcina frisia
Author(s) -
Turkowsky Anja,
Blotevogel KarlHeinz,
Fischer Ulrich
Publication year - 1991
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1991.tb04767.x
Subject(s) - thiosulfate , rhodanese , chemistry , sulfur , biochemistry , cyanide , methanosarcina barkeri , sulfite , enzyme , inorganic chemistry , organic chemistry , methanogenesis , methane
Cell‐free extracts of Methanosarcina frisia contain high thiosulfate sulfur transferase (TST) (rhodanese), slight thiosulfate reductase but no thiosulfate: acceptor oxidoreductase activity. Neither adenylylsulfate reductase nor sulfite: acceptor oxidoreductase activity could be detected. TST is an acidic protein with an M r of 25 000 and was enriched by ion‐exchange chromatography and gel filtration. The enzyme has a temperature optimum at 60°C and a pH optimum at pH 11. The K m values for thiosulfate and cyanide are 0.53 mM and 1.57 mM, respectively. Low concentrations of cysteine, glutathione, dithioerythritol, and dihydrolipoate increase the activity of the enzyme while unphysiological concentrations of these effectors cause a decrease. Sulfite and N ‐bromosuccinimide inhibit the energy activity extremely.