Lipid-Dependent Titration of Glutamic Acid at a Bilayer Membrane Interface.

ABSTRACT: The ionization properties of protein side chains in lipid-bilayer membranes will differ from the canonical values of side chains exposed to an aqueous solution. While the propensities of positively charged side chains of His, Lys, and Arg to release a proton in lipid membranes have been rather well characterized, the propensity for a negatively charged Glu side chain to receive a proton and achieve the neutral state in a bilayer membrane has been less well characterized. Indeed, the ionization of the glutamic acid side chain has been predicted to depend on its depth of burial in a lipid membrane but has been difficult to verify experimentally. To address the issue, we incorporated an interfacial Glu residue at position 4 of a distinct 23-residue transmembrane helix and used ²H N

SUBMITTER: McKay MJ 

PROVIDER: S-EPMC8015139 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature