A vibrational spectral maker for probing the hydrogen-bonding status of protonated Asp and Glu residues.

ABSTRACT: Hydrogen bonding is a fundamental element in protein structure and function. Breaking a single hydrogen bond may impair the stability of a protein. We report an infrared vibrational spectral marker for probing the hydrogen-bond number for buried, protonated Asp or Glu residues in proteins. Ab initio computational studies were performed on hydrogen-bonding interactions of a COOH group with a variety of side-chain model compounds of polar and charged amino acids in vacuum using density function theory. For hydrogen-bonding interactions with polar side-chain groups, our results show a strong correlation between the C=O stretching frequency and the hydrogen bond number of a COOH group: approximately 1759-1776 cm(-1) for zero, approximately 1733-1749 cm(-1) for one, and 1703-1710 cm(-1) for two

SUBMITTER: Nie B 

PROVIDER: S-EPMC1305378 | biostudies-literature | 2005 Apr

REPOSITORIES: biostudies-literature