Unexpected Gating Behaviour of an Engineered Potassium Channel Kir

Autor: Charline Fagnen, Ludovic Bannwarth, Dania Zuniga, Iman Oubella, Rita De Zorzi, Eric Forest, Rosa Scala, Samuel Guilbault, Saïd Bendahhou, David Perahia, Catherine Vénien-Bryan
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: Frontiers in Molecular Biosciences, Vol 8 (2021)
Druh dokumentu: article
ISSN: 2296-889X
DOI: 10.3389/fmolb.2021.691901
Popis: In this study, we investigated the dynamics and functional characteristics of the KirBac3.1 S129R, a mutated bacterial potassium channel for which the inner pore-lining helix (TM2) was engineered so that the bundle crossing is trapped in an open conformation. The structure of this channel has been previously determined at high atomic resolution. We explored the dynamical characteristics of this open state channel using an in silico method MDeNM that combines molecular dynamics simulations and normal modes. We captured the global and local motions at the mutation level and compared these data with HDX-MS experiments. MDeNM provided also an estimation of the probability of the different opening states that are in agreement with our electrophysiological experiments. In the S129R mutant, the Arg129 mutation releases the two constriction points in the channel that existed in the wild type but interestingly creates another restriction point.
Databáze: Directory of Open Access Journals