Interaction between γC87 and γR242 residues participates in energy coupling between catalysis and proton translocation in Escherichia coli ATP synthase.

ABSTRACT: Functioning as a nanomotor, ATP synthase plays a vital role in the cellular energy metabolism. Interactions at the rotor and stator interface are critical to the energy transmission in ATP synthase. From mutational studies, we found that the γC87K mutation impairs energy coupling between proton translocation and nucleotide synthesis/hydrolysis. An additional glutamine mutation at γR242 (γR242Q) can restore efficient energy coupling to the γC87K mutant. Arrhenius plots and molecular dynamics simulations suggest that an extra hydrogen bond could form between the side chains of γC87K and βTPE381 in the γC87K mutant, thus impeding the free rotation of the rotor complex. In the enzyme with γC87K/γR242Q double mutations, the polar moiety of γR242Q side chain can form a hydrogen bond with γC87K,

SUBMITTER: Li Y 

PROVIDER: S-EPMC6668360 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature