Purification and characterization of mouse liver glyoxalase II

Glyoxalase II (S2-hydroxyacylglutatione hydrolase, EC 3.1.2.6) was purified from Swiss mouse liver to homogeneity by a rapid, two-step affinity chromatographic scheme. Homogeneity was established by multiple electrophoretic determinations. The purified enzyme exhibited a specific activity of 920 I.U./mg protein and has a molecular weight of approx. 29 500 as estimated by SDS polyacrylamide gel electrophoresis. The enzyme is a basic protein with a pI of approx. 8.1. Mouse liver glyoxalase II is competitively inhibited by the substrate of glyoxalase I (the hemimercaptal of methylglyoxal and glutathione); the Ki is 0.3 mM. The Km for S-D-lactoylglutathione is 0.27 mM, and the enzyme has a turnover number of approx. 27 000 mumol substrate per min per mumol enzyme.