1WQM

CONTRIBUTION OF HYDROGEN BONDS TO THE CONFORMATIONAL STABILITY OF HUMAN LYSOZYME

Summary for 1WQM

• Entry DOI: 10.2210/pdb1wqm/pdb
• Descriptor: LYSOZYME, SODIUM ION, CHLORIDE ION, ... (4 entities in total)
• Functional Keywords: hydrolase (o-glycosyl), glycosidase, bacteriolytic enzyme, hydrolase
• Biological source: Homo sapiens (human)
• Cellular location: Secreted: P61626
• Total number of polymer chains: 1
• Total formula weight: 14798.59

Authors

Yamagata, Y.,Kubota, M.,Sumikawa, Y.,Funahashi, J.,Fujii, S.,Yutani, K. (deposition date: 1998-02-09, release date: 1998-07-01, Last modification date: 2024-04-03)

Primary citation

Yamagata, Y.,Kubota, M.,Sumikawa, Y.,Funahashi, J.,Takano, K.,Fujii, S.,Yutani, K.
Contribution of hydrogen bonds to the conformational stability of human lysozyme: calorimetry and X-ray analysis of six tyrosine --> phenylalanine mutants.
Biochemistry, 37:9355-9362, 1998

PubMed Abstract: 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.

PubMed: 9649316
DOI: 10.1021/bi980431i

Experimental method

X-RAY DIFFRACTION (1.8 Å)