Chloroplast sulfhydryl groups and the light activation of fructose-1,6-bisphosphatase.
نویسندگان
چکیده
Studies of isolated intact spinach (Spinacia oleracea L.) chloroplasts reveal that most of the available sulfhydryl groups are associated with stromal protein as opposed to a thylakoid membrane fraction under non-denaturing conditions. Increases in sulfhydryl content of approximately 50% occurred with illumination and could be correlated kinetically with a reductive activation of fructose-1,6-bisphosphatase during CO(2)-assimilation. Inhibition of linear electron flow with 3-(3,4-dichlorophenyl)-1,1-dimethylurea prevented light driven increases in both fructose-1,6-bisphosphatase activity and the relative sulfhydryl number. These results provide evidence for the operation of a reductive enzyme activating system in vivo.
منابع مشابه
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ورودعنوان ژورنال:
- Plant physiology
دوره 70 4 شماره
صفحات -
تاریخ انتشار 1982