Arginine side chain interactions and the role of arginine as a gating charge carrier in voltage sensitive ion channels.

ABSTRACT: Gating charges in voltage-sensing domains (VSD) of voltage-sensitive ion channels and enzymes are carried on arginine side chains rather than lysine. This arginine preference may result from the unique hydration properties of the side chain guanidinium group which facilitates its movement through a hydrophobic plug that seals the center of the VSD, as suggested by molecular dynamics simulations. To test for side chain interactions implicit in this model we inspected interactions of the side chains of arginine and lysine with each of the 19 non-glycine amino acids in proteins in the protein data bank. The arginine guanidinium interacts with non-polar aromatic and aliphatic side chains above and below the guanidinium plane while hydrogen bonding with polar side chains is restricted to in-pla

SUBMITTER: Armstrong CT 

PROVIDER: S-EPMC4761985 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature