Structural elements involved in ATP hydrolysis inhibition and ATP synthesis of tuberculosis and non-tuberculous mycobacterial F-ATP synthase decipher new targets for inhibitors

Abstract

The F1FO-ATP synthase is required for the viability of tuberculosis- (TB) and non- tuberculous mycobacteria (NTM) and has been validated as a drug-target. Here, we present the cryo-EM structures of the Mycobacterium smegmatis F1-ATPase and the F1FO-ATP synthase with different nucleotide occupation within the catalytic sites and visualize critical elements for latent ATP hydrolysis and efficient ATP synthesis. Mutational studies reveal that the extended C-terminal domain (αCTD) of subunit α is the main element for the self-inhibition mechanism of ATP hydrolysis for TB and NTM bacteria. Rotational studies indicate that the transition between the inhibition state by the ɑCTD and the active state is a rapid process. We 40 demonstrate that the unique mycobacterial γ-loop and subunit δ are critical elements required for ATP formation. The data underline that these mycobacterium specific elements of α, γ and δ are attractive targets, providing a platform for the discovery of species-specific inhibitors.