[Covalent binding of 1,N(6)-ethenoadenosine diphosphate to catalytic and noncatalytic sites of chloroplast ATP-synthase].
The catalytic and noncatalytic sites of the chloroplast coupling factor (CF1) were selectively modified by incubation with the dialdehyde derivative of the fluorescent adenosine diphosphate analogue 1,N(6)-ethenoadenosine diphosphate. The modified CF1 was reconstituted with EDTA-treated chloroplast thylakoid membranes. The influence of light-induced transmembrane proton gradient and of phosphate ions on the fluorescence of 1,N(6)-ethenoadenosine diphosphate covalently bound to catalytic sites of reconstituted CF1 (ATP-synthase) was studied. Upon illumination of thylakoid membranes with saturating white light, the quenching of fluorescence of covalently bound 1,N(6)-ethenoadenosine diphosphate was observed. The quenching was reversed by the addition of inorganic phosphate to the reaction mixture in the dark. Repeated illumination induced the quenching once again: however, the addition of phosphate ions did not affect the fluorescence intensity now. When 1,N(6)-ethenoadenosine diphosphate was covalently bound to noncatalytic sites of ATP-synthase, no similar fluorescent changes were observed. The interrelation of the observed changes of 1,N(6)-ethenoadenosine diphosphate fluorescence and the mechanism of energy-dependent changes in the structure of the catalytic site of ATP-synthase is discussed.
Tatarintsev
N P
NP
Mal'ian
A N
AN
D000244:Adenosine Diphosphate / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000737:chemistry / Q000378:metabolism; D020134:Catalytic Domain / Q000187:drug effects; D025222:Chloroplast Proton-Translocating ATPases / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000378:metabolism; D005456:Fluorescent Dyes / Q000737:chemistry / Q000494:pharmacology*; D008027:Light; D018532:Pisum sativum / Q000737:chemistry / Q000201:enzymology*; D010940:Plant Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000378:metabolism; D011485:Protein Binding / Q000187:drug effects; D020524:Thylakoids / Q000737:chemistry / Q000201:enzymology*
D005456:Fluorescent Dyes; D010940:Plant Proteins; C015195:1,N(6)-ethenoadenosine diphosphate; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D025222:Chloroplast Proton-Translocating ATPases