ATP binding and hydrolysis steps of the uni-site catalysis by the mitochondrial F-1-ATPase are affected by inorganic phosphate

作者：Milgrom Yakov M^*

来源：Biochimica et Biophysica Acta-Bioenergetics, 2010, 1797(10): 1768-1774.

DOI：10.1016/j.bbabio.2010.07.010

• ATP synthase
• Uni-site catalysis
• Bi-site catalysis
• Multi-site catalysis
• Phosphate

The effect of inorganic phosphate (P-i) on uni-site ATP binding and hydrolysis by the nucleotide-depleted F-1-ATPase from beef heart mitochondria (ndMF(1)) has been investigated. It is shown for the first time that P-i decreases the apparent rate constant of uni-site ATP binding by ndMF(1) 3-fold with the K-d of 0.38 +/- 0.14 mM. During uni-site ATP hydrolysis, P-i also shifts equilibrium between bound ATP and ADP + P-i in the direction of ATP synthesis with the K-d of 0.17 +/- 0.03 mM. However, 10 mM P-i does not significantly affect ATP binding during multi-site catalysis.

• 出版日期2010-10