The nucleotide binding site of F1‐ATPase which carries out uni‐site catalysis is one of the alternating active sites of the enzyme

FEBS Letters

Milgrom, Ya.M.¹  Murataliev, M.B.¹  Kozlov, I.A.¹  Vulfson, E.N.¹ 

[1] A.N. Belozersky Laboratory of Molecular Biology and Bioorganic Chemistry, Moscow State University, Moscow 119899, USSR

关键词: F1-ATPase;    Uni-site catalysis;    Photoactive nucleotide analog;    NAB-AD(T)P;    3'(2')-O-(2-nitro-4-azidobenzoyl) adenosine-5'-di(tri)phosphate;    NAB-GD(T)P;    3'(2')-O-(2-nitro-4-azidobenzoyl)guanosine-5'-di(tri)phosphate;    Mops;    4-morpholinepropanesulfonic acid;   

DOI  :  10.1016/0014-5793(85)81041-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

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·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.

【 授权许可】

Unknown