A comprehensive Analysis of the Computed Tautomer Fractions of the Imidazole Ring of Histidines in Loligo vulgaris

VOROBJEV Y.N.; SCHERAGA H.A.; VILA, J.A.

JOURNAL OF BIOMOLECULAR STRUCTURE & DYNAMICS

ADENINE PRESS

Año: 2017

0739-1102

Arecently introduced electrostatic-based method to determine the pKa values ofionizable residues and fractions of ionized and tautomeric forms of histidine(His) and acid residues in proteins, at a given fixed pH, is applied here tothe analysis of a His-rich protein, namely Loligovulgaris (pdb id 1E1A), a314-residue all-b protein. The average tautomeric fractionsfor the imidazole ring of each of the six histidines in the sequence werecomputed by using an approach that includes, but is not limited to, moleculardynamic simulations coupled with calculations of the ionization states for all94 ionizable residues of protein 1E1A in water at pH 6.5 and 300 K.