Some Properties of the DCMU-Binding Site in Chloroplasts

نویسندگان

  • Wolfgang Tischer
  • Heinrich Strotmann
چکیده

Binding of the triazinone derivative metribuzin to thylakoid membranes was studied in depend­ ence of tem perature and trypsin pre-treatm ent of the chloroplasts. The tem perature curve of the binding constant suggests that the lipid phase of the membrane contributes to inhibitor binding. Trypsin pre-treatm ent of the membranes removes the receptor sites for the inhibitor, while the trypsin effect on the affinity of the receptor to the inhibitor is marginal. Concomitantly trypsin treatm ent releases the inhibitory effect of metribuzin on the electron transport from DPC to DCPIP.

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تاریخ انتشار 2013