Structure of F 1 -ATPase from the obligate anaerobe Fusobacterium nucleatum

Abstract

The crystal structure of the F 1 -catalytic domain of the adenosine triphosphate (ATP) synthase has been determined from the pathogenic anaerobic bacterium Fusobacterium nucleatum . The enzyme can hydrolyse ATP but is partially inhibited. The structure is similar to those of the F 1 -ATPases from Caldalkalibacillus thermarum , which is more strongly inhibited in ATP hydrolysis, and in Mycobacterium smegmatis , which has a very low ATP hydrolytic activity. The β E -subunits in all three enzymes are in the conventional ‘open’ state, and in the case of C. thermarum and M. smegmatis , they are occupied by an ADP and phosphate (or sulfate), but in F. nucleatum , the occupancy by ADP appears to be partial. It is likely that the hydrolytic activity of the F. nucleatum enzyme is regulated by the concentration of ADP, as in mitochondria.