The nucleotide binding site of F1-ATPase which carries out uni-site catalysis is one of the alternating active sites of the enzyme.
Nucleotide-depleted mitochondrial F1-ATPase binds 3'-(2')-O-(2-nitro-4-azidobenzoyl)-derivatives of ATP (NAB-ATP) and GTP (NAB-GTP) when these nucleotide analogues are added to the enzyme in equimolar quantities in the presence of Mg2+ (uni-site catalysis conditions). The binding of NAB-ATP is accompanied by its hydrolysis and inorganic phosphate dissociation from the enzyme; NAB-ADP remains bound to F1-ATPase. The F1-ATPase X NAB-ADP complex has no ATPase activity and its reactivation in the presence of an excess of ATP is accompanied by NAB-ADP release. The illumination of the F1-ATPase complexes with NAB-ADP or NAB-GDP leads to the covalent binding of one nucleotide analogue molecule to the enzyme and to the irreversible inactivation of F1-ATPase. It follows from the results obtained that the modification of just one of the F1-ATPase catalytic sites is sufficient to complete the inhibition of ATPase activity.
Kozlov
I A
IA
Milgrom YaM
Murataliev
M B
MB
Vulfson
E N
EN
D000255:Adenosine Triphosphate / Q000031:analogs & derivatives / Q000378:metabolism; D000818:Animals; D001665:Binding Sites; D006160:Guanosine Triphosphate / Q000031:analogs & derivatives / Q000378:metabolism; D007700:Kinetics; D008274:Magnesium / Q000378:metabolism; D008928:Mitochondria / Q000201:enzymology; D009711:Nucleotides / Q000378:metabolism*; D006180:Proton-Translocating ATPases / Q000378:metabolism*
D009711:Nucleotides; D006160:Guanosine Triphosphate; D000255:Adenosine Triphosphate; C046623:3'(2')-O-(2-nitro-4-azidobenzoyl)adenosine 5'-triphosphate; C046624:3'(2')-O-(2-nitro-4-azidobenzoyl)guanosine 5'-triphosphate; D006180:Proton-Translocating ATPases; D008274:Magnesium