Dynamic mechanisms driving conformational conversions of the β and ε subunits involved in rotational catalysis of F1-ATPase

F-type atpase is a ubiquitous molecular motor. investigations on thermophilic f1-atpase and its subunits,β and ε,by nmr were reviewed. using specific isotope labeling,pka of the putative catalytic carboxylate in β was estimated. segmental isotope-labeling enabled us to monitor most residues of β,revealing that the conformational conversion from open to closed form of β on nucleotide binding found in atpase was an intrinsic property of β and could work as a driving force of the rotational catalysis. a stepwise conformational change was driven by switching of the hydrogen bond networks involving walker a and b motifs. segmentally labeled atpase provided a well resolved nmr spectra,revealing while the open form of β was identical for β monomer and atpase,its closed form could be different. atp-binding was also a critical factor in the conformational conversion of ε,an atp hydrolysis inhibitor. its structural elucidation was described. © 2017 the japan academy.