THE STUDY ON THE MECHANISMS OF RADICAL FORMATION IN THE REACTION BETWEEN HA AND CYSTEINE IN THE PRESENCE
竹红菌甲素与半胱氨酸作用的ESR研究

The mechanisms of radical generation in the rection both HA and cysteine were investigated with ESR and chemical techniques in this paper. The evidences showed that HA acted as a mediator in the redox Cycling, i.e. electrons were transported from sulfhydrylcompounds to HA, and in turn, relayed to oxygen forming superoxide anion radical in dark. This process can be enhanced by illumination. We found Synevgic action were existed between reaction in dark and in light which strongly suggested that excited HA reacting with cysteine would be faster than that of HA in ground state. Besides cysteine, mercaptoethanol and reduced glutathione were also capable of denoting their electrons to oxygen mediated by HA, but it was failure in the case of cystine and methionine, which indicated that sulfhydryl groups were improtant in the reaction rather than sulfuric atoms.