An enzyme capable of hydrolysing tetrathionate was purified from cell-free extracts of Thiobacillus acidophilus. The purified enzyme converts tetrathionate into thiosulfate, sulfur and sulfate. In addition, pentathionate could also be converted by the same enzyme. Measurement of the enzyme activity during purification is based on the absorbance of the initial intermediates formed from tetrathionate in the ultraviolet region, which have not been identified. Enzyme activity could also be measured by the scattering of insoluble sulfur in the visible region. The purified enzyme has a pH optimum of 2.5 and a temperature optimum of 65°C. Enzyme activity is strongly stimulated by the presence of sulfate ions. The purified enzyme is a dimer with two identical subunits of 48kDa. The ultraviolet–visible absorption spectra and denaturation experiments indicate the presence of an organic cofactor.
If you can't find a tool you're looking for, please click the link at the top of the page to "Go to old article view". Alternatively, view our Knowledge Base articles for additional help. Your feedback is important to us, so please let us know if you have comments or ideas for improvement.
Isocitric dehydrogenase (EC 126.96.36.199)
alcohol dehydrogenase (EC 188.8.131.52)