Interaction between ΓC87 and ΓR242 residues participates in energy coupling between catalysis and proton translocation in escherichia coli ATP synthase

Date
2019
Authors
Li, Yunxiang
Ma, Xinyou
Weber, Joachim
Journal Title
Journal ISSN
Volume Title
Publisher
Elsevier
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, so that the amine group in the side chain of γC87K will not hydrogen-bond with βE381. As a conclusion, the intra-subunit interaction between positions γC87 and γR242 modulates the energy transmission in ATP synthase. This study should provide more information of residue interactions at the rotor and stator interface in order to further elucidate the energetic mechanism of ATP synthase.

Description
Article originally published in Biochimica Et Biophysica Acta (BBA) - Bioenergetics, 1860(8), 679–687. English. Published online 2019. https://doi.org/10.1016/j.bbabio.2019.06.016
Keywords
ATP synthase, Energy transmission, Molecular dynamics, Mutational study, Residue interaction
Citation
This is the post-print version of an article that is available at https://doi.org/10.1016/j.bbabio.2019.06.016. Recommended citation: Li, Y., Ma, X., & Weber, J. (2019). Interaction between ΓC87 and ΓR242 residues participates in energy coupling between catalysis and proton translocation in escherichia coli ATP synthase. Biochimica Et Biophysica Acta (BBA) - Bioenergetics, 1860(8), 679–687. This item has been deposited in accordance with publisher copyright and licensing terms and with the author’s permission.