Salvaging the Thermodynamic Destabilization of Interface Histidine in Transmembrane β-Barrels.

ABSTRACT: The ability of histidine to participate in a wide range of stabilizing polar interactions preferentially populates this residue in functionally important sites of proteins. Histidine possesses an amphiphilic and electrostatic nature that is essential for amino acids residing at membrane interfaces. However, the frequency of occurrence of histidine at membrane interfaces, particularly transmembrane β-barrels, is lower than those of other aromatic residues. Here, we carry out comprehensive energetic measurements using equilibrium folding of the outer membrane enzyme PagP to address the contribution of a C-terminal interface histidine to barrel stability. We show that placing histidine at the C-terminus universally destabilizes PagP by 4.0-8.0 kcal mol^-1 irrespective of the neighbo

SUBMITTER: Iyer BR 

PROVIDER: S-EPMC6284319 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature