Thioester hydrolysis promoted by a mononuclear zinc complex.

The mononuclear zinc complex (bpta)Zn(2).0.5H(2)O promotes the hydrolysis of the thioester PhCH(OH)C(O)SCD(3) when dissolved in CH(3)CN:H(2)O (50:50 buffered at pH 9.0). This reaction results in the formation of a mixture of CD(3)SH and a zinc thiolate complex, the latter of which can be protonated to generate additional CD(3)SH. Kinetic studies revealed an overall second-order reaction with an activation energy that is similar to that found for aqueous OH(-) promoted thioester hydrolysis. These studies represent the first investigation of chemistry relevant to that occurring in the monozinc-containing form of human glyoxalase II.