ATP synthase: expression, purification, and function

ATP synthase is an essential enzyme found in all known forms of life, generating the majority of cellular energy via a rotary catalytic mechanism. Here, we describe the in-depth methods for expression, purification, and functional assessment of E. coli ATP synthase

Bcl-xl regulates metabolic efficiency of neurons through interaction with the mitochondrial F1FoATP synthase

Anti-apoptotic Bcl2 family proteins such as Bcl-xL protect cells from death by sequestering apoptotic molecules, but also contribute to normal neuronal function. We find in hippocampal neurons that Bcl-xL enhances the efficiency of energy metabolism. Our evidence indicates that Bcl-xLinteracts directly with the ?-subunit of the F1FO ATP synthase, decreasing an ion leak within the F1FO ATPase complex and thereby increasing net transport of H+ by F1FO during F1FO ATPase activity. By patch clamping submitochondrial vesicles enriched in F1FO ATP synthase complexes, we find that, in the presence of ATP, pharmacological or genetic inhibition of Bcl-xL activity increases the membrane leak conductance. In addition, recombinant Bcl-xL protein directly increases the level of ATPase activity of purified synthase complexes, and inhibition of endogenous Bcl-xL decreases the level of F1FO enzymatic activity. Our findings indicate that increased mitochondrial efficiency contributes to the enhanced synaptic efficacy found in Bcl-xL-expressing neurons