Open AccessMetabolism of tetrathionate in Thiobacillus acidophilus
Author(s) -
Meulenberg Rogier,
Scheer Erik J.,
Pronk Jack T.,
Hazeu Wim,
Bos Piet,
Gijs Kuenen J.
Publication year - 1993
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.1574-6968.1993.tb06443.x
Subject(s) - tetrathionate , chemistry , ammonium , incubation , enzyme , enzyme assay , thiosulfate , biochemistry , sulfur , thiobacillus , chromatography , nuclear chemistry , organic chemistry
Cell‐free extracts of Thiobacillus acidophilus catalysed the stoichiometric conversion of tetrathionate to thiosulphate, sulphur and two protons. The pH optimum of the enzyme activity was 3.0 and its temperature optimum 40°C. The enzyme was unstable at 30 and 40°C, at which its activity decreased to zero within 100 and 20 h, respectively. Enzyme activity was not affected by incubation for 1 week on ice or by freezing and thawing of the extract. The K m for tetrathionate was 0.3 mM. Enzyme activity was stimulated by ammonium sulphate up to a concentration of 1M. The results indicate that trithionate hydrolase cannot account for the observed conversion of tetrathionate.