earticle

영어

The 31P NMR spectroscopy of native Escherichia coli F1-ATPAse (EF1) showed 31P resonance from free AMP, indicating adenylate kinase-like activity of F1-ATPase. However, 31P resonance from free AMP did not appear in the presence of the methanol which is known to stabilize F1-ATPase. The presence of methanol could have affected on the interaction with nucleotides bound to EF1 and inhibited adenylate kinase-like activity of EF1. Monitoring of very slow adenylate-kinase like activity is only possible from 31P NMR spectroscopy. 31P resonances of EF1 bound nucleotides were more clearly resolved in the absence of methanol than those of in the presence of methanol, which demonstrates the interaction of methanol with nucleotides binding sites of EF1. The separated resonances in the region of β phosphate of ADP in the absence of methanol might suggest structural asymmetry amongst nucleotide binding sites of EF1 in the various conditions. 31P NMR proved to be a valuable tool for investigating phosphorous related enzymes.