Does F1-ATPase have a catalytic site that preferentially binds MgADP?
During ATP synthesis, ATP synthase has to bind MgADP in the presence of an excess of MgATP. Thus, for efficient ATP synthesis it would be desirable if incoming substrate could be bound to a catalytic site with a preference for MgADP over MgATP. We tested three hypotheses predicting the existence of such a site. However, our results showed that, at least in absence of an electrochemical proton gradient, none of the three catalytic sites has a higher affinity for MgADP than for MgATP.
Mao
Hui Z
HZ
Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409, USA.
Gray
Wesley D
WD
Weber
Joachim
J
D000244:Adenosine Diphosphate / Q000737:chemistry* / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000096:biosynthesis / Q000737:chemistry; D020134:Catalytic Domain / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D008274:Magnesium / Q000737:chemistry* / Q000378:metabolism; D009154:Mutation; D011485:Protein Binding / Q000235:genetics; D006180:Proton-Translocating ATPases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D013050:Spectrometry, Fluorescence
D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D006180:Proton-Translocating ATPases; D008274:Magnesium