CONFORMATIONAL TRANSMISSION IN ATP SYNTHASE DURING CATALYSIS - SEARCHFOR LARGE STRUCTURAL-CHANGES

Escherichia coli ATP synthase has eight subunits and functions through transmission of conformational changes between subunits. Defective mu tation at beta Gly-149 was suppressed by the second mutations at the o uter surface of the beta subunit, indicating that the defect by the fi rst mutation was suppressed by the second mutation through long range conformation transmission. Extensive mutant/pseudorevertant studies re vealed that beta/alpha and beta/gamma subunits interactions are import ant for the energy coupling between catalysis and H+ translocation. In addition, long range interaction between amino and carboxyl terminal regions of the gamma subunit has a critical role(s) for energy couplin g. These results suggest that the dynamic conformation change and its transmission are essential for ATP synthase.