1wqq
From Proteopedia
CONTRIBUTION OF HYDROGEN BONDS TO THE CONFORMATIONAL STABILITY OF HUMAN LYSOZYME
Overview
The contribution of hydrogen bonds to the conformational stability of human lysozyme was investigated by the combination of calorimetric and X-ray analyses of six Tyr --> Phe mutants. Unfolding Delta G and unfolding Delta H values of the Tyr --> Phe mutant proteins were changed by from +0.3 to -4.0 kJ/mol and from 0 to -16 kJ/mol, respectively, compared to those of the wild-type protein. The net contribution of a hydrogen bond at a specific site to stability (Delta Gwild/HB), considering factors affected by substitutions, was evaluated on the basis of X-ray structures of the mutant proteins. In the present study, one of six mutant proteins was suitable for evaluating the strength of the hydrogen bond. Delta Gwild/HB for the intramolecular hydrogen bond at Tyr124 was evaluated to be 7.5 kJ/mol. Results of the analysis of other mutants also suggest that hydrogen bonds of the hydroxyl group of Tyr, including the hydrogen bond with a water molecule, contribute to the stabilization of the human lysozyme.
About this Structure
1WQQ is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Contribution of hydrogen bonds to the conformational stability of human lysozyme: calorimetry and X-ray analysis of six tyrosine --> phenylalanine mutants., Yamagata Y, Kubota M, Sumikawa Y, Funahashi J, Takano K, Fujii S, Yutani K, Biochemistry. 1998 Jun 30;37(26):9355-62. PMID:9649316 Page seeded by OCA on Sat May 3 14:01:27 2008
