Anions induce conformational changes and influence the activity and photoaffinity-labelling by 8-azido-ATP of isolated cytochrome c oxidase.
نویسندگان
چکیده
The biphasic effect of anions on the activity of isolated bovine heart cytochrome c oxidase is paralleled by changes in the visible oxidized spectra, indicating the different conformational changes in the enzyme induced by bromide, chloride, sulphate, phosphate, ADP and ATP. Photoaffinity-labelling of most subunits of the isolated enzyme by low concentrations of 8-azido-[gamma-32P]ATP is strongly increased by ATP, ADP and unlabelled 8-azido-ATP in an unspecific manner. With the reconstituted enzyme less subunits are labelled and this labelling is only little affected by nucleotides. The data suggest a highly dynamic structure for isolated bovine heart cytochrome c oxidase.
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ورودعنوان ژورنال:
- The Biochemical journal
دوره 254 3 شماره
صفحات -
تاریخ انتشار 1988