Inactivation of Glutamie-Aspartic Transaminase by Irradiation.

Abstract

Glutamic-aspartic transaminase is inactivated by sunlight and by ultraviolet light. Destruction of enzymatic activity by these agents parallels the destruction of vitamin B6, a derivative of which is present as the prosthetic group of the enzyme. The irradiated enzyme is not reactivated by addition of pyridoxine, pyridoxal, pyridox-amine or boiled tissue extracts. Irradiation with X-rays leaves the enzyme intact.