Purification and characterization of glutathione transferase of human thyroid
Del Boccio, G.; Di Ilio, C.; Casalone, E.; Pennelli, A.; Aceto, A.; Sacchetta, P.; Federici, G.
Italian Journal of Biochemistry 36(1): 8-17
1987
ISSN/ISBN: 0021-2938 PMID: 3583687 Document Number: 289879
An anionic (pI 4.6) isoenzyme of glutathione transferase was purified to homogeneity from human thyroid by affinity chromatography followed by isoelectric focusing. The content of enzyme was calculated to constitute about 0.2% of soluble proteins. The enzyme is formed by two identical subunits of 23,000 daltons approximately. The thyroid transferase did not catalyze the reduction of peroxides. Physical, catalytic and immunological analyses demonstrated extensive similarities between the thyroid transferase and the transferase from placenta, erythrocytes and breast. On the other hand, the thyroid transferase appears catalytically different from transferase 7-7, even if both cross-react with the antibodies raised against human placenta transferase.