Carbocation Footprinting of Soluble and Transmembrane Proteins.

ABSTRACT: Here, we introduce carbocations (R₃C⁺) as laser-initiated footprinting reagents for proteins. We screened seven candidates and selected trifluomethoxy benzyl bromide (TFBB) as an effective precursor for the electrophilic trifluomethoxy benzyl carbocation (TFB⁺) under laser (248 nm) irradiation on the fast photochemical oxidation of proteins (FPOP) platform. Initial results demonstrate that this electrophilic cation reagent affords residue coverage of nucleophilic amino acids including H, W, M, and S. Further, the addition of TFB⁺ increases the hydrophobicity of the peptides so that separation of isomeric peptide products by reversed-phase LC is improved, suggesting opportunities for subresidue footprinting. Comparison of apo- and holo-myoglobin f

SUBMITTER: Sun J 

PROVIDER: S-EPMC8900486 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature