在碘化物氧化过程中乳过氧化物酶的不可逆失活。

Irreversible inactivation of lactoperoxidase in the course of iodide oxidation.

作者信息

Jenzer H, Bürgi U, Kohler H

出版信息

Biochem Biophys Res Commun. 1987 Jan 30;142(2):552-8. doi: 10.1016/0006-291x(87)90309-3.

Abstract

In the course of lactoperoxidase-catalysed I- oxidation, which is a model for the initial step of thyroid hormone biosynthesis, irreversible enzyme inactivation can occur if free molecular iodine (I2) or other oxidized iodine species accumulate. Evidence is presented that the breakdown of the catalytic activity is the result of the iodination of the peroxidase-apoprotein. This kind of enzyme inactivation, which can be prevented by iodine acceptors' such as thyroglobulin or high concentrations of I-, may well play a role in the regulation of the synthesis of thyroid hormones in vivo.

摘要

在乳过氧化物酶催化的碘氧化过程中（这是甲状腺激素生物合成初始步骤的一个模型），如果游离分子碘（I₂）或其他氧化态碘物种积累，可能会发生不可逆的酶失活。有证据表明，催化活性的丧失是过氧化物酶脱辅基蛋白碘化的结果。这种酶失活可被碘受体（如甲状腺球蛋白或高浓度的碘离子）阻止，很可能在体内甲状腺激素合成的调节中发挥作用。