Near UV-Visible electronic absorption originating from charged amino acids in a monomeric protein.

ABSTRACT: Electronic absorption spectra of proteins are primarily characterized over the ultraviolet region (185-320 nm) of the electromagnetic spectrum. While recent studies on peptide aggregates have revealed absorption beyond 350 nm, monomeric proteins lacking aromatic amino acids, disulphide bonds, and active site prosthetic groups are expected to remain optically silent beyond 250 nm. Here, in a joint theoretical and experimental investigation, we report the distinctive UV-Vis absorption spectrum between 250 nm [ε = 7338 M^-1 cm^-1] and 800 nm [ε = 501 M^-1 cm^-1] in a synthetic 67 residue protein (α₃C), in monomeric form, devoid of aromatic amino acids. Systematic control studies with high concentration non-aromatic amino acid so

SUBMITTER: Prasad S 

PROVIDER: S-EPMC5609530 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature