Mitochondria in L. edodes were separated and purified by stepped sucrose density gradient centrifugation. In our previous work, we have found that the activation wavelengths of the mitochondrial ATPase and ATP synthase were 680 ㎚ and 470 ㎚ within the range of 400-700 ㎚, respectively.
The activities of the above enzymes with wavelengths of 300-400 ㎚ region were investigated. The mitochondrial ATPase and ATP synthase were stimulated at 380 ㎚ and 330 ㎚, respectively, for 30 min illumination compared with dark control group. They, however, were inhibited at 330 ㎚ and 350 ㎚, respectively. The presence of FAD resulted in inhibition of the activity of the ATPase and stimulation of the activity of the ATP synthase by the activation and inhibition wavelengths. However, the activities of these enzymes were not changed by NADH for the above wavelengths. In the spectral properties, the oxidation of FADHZ into FAD occurs in the presence of the enzymes for illumination of the activation and inhibition wavelengths. Therefore, we can predict that the mitochondria) ATPase and ATP synthase may function as oxidant in the redox reaction by the light illumination and that the light-induced pigment of the mitochondrial ATP synthase should be an oxidized form of a flavoprotein.
|