Chloroplast sulfhydryl groups and the light activation of fructose-1,6-bisphosphatase.

نویسندگان

  • R E Slovacek
  • S Vaughn
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.

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عنوان ژورنال:
  • Plant physiology

دوره 70 4  شماره 

صفحات  -

تاریخ انتشار 1982