1IP5

G105A HUMAN LYSOZYME

Summary for 1IP5

• Entry DOI: 10.2210/pdb1ip5/pdb
• Related: 1GDW 1IP1 1IP2 1IP3 1IP4 1IP6 1IP7
• Descriptor: LYSOZYME C, SODIUM ION (3 entities in total)
• Functional Keywords: glycosidase, bacteriolytic enzyme, hydrolase
• Biological source: Homo sapiens (human)
• Cellular location: Secreted: P61626
• Total number of polymer chains: 1
• Total formula weight: 14757.71

Authors

Takano, K.,Yamagata, Y.,Yutani, K. (deposition date: 2001-04-20, release date: 2001-11-14, Last modification date: 2024-10-16)

Primary citation

Takano, K.,Yamagata, Y.,Yutani, K.
Role of amino acid residues in left-handed helical conformation for the conformational stability of a protein.
Proteins, 45:274-280, 2001

PubMed Abstract: Our previous study of six non-Gly to Gly/Ala mutant human lysozymes in a left-handed helical region showed that only one non-Gly residue at a rigid site had unfavorable strain energy as compared with Gly at the same position (Takano et al., Proteins 2001; 44:233-243). To further examine the role of left-handed residues in the conformational stability of a protein, we constructed ten Gly to Ala mutant human lysozymes. Most Gly residues in human lysozyme are located in the left-handed helix region. The thermodynamic parameters for denaturation and crystal structures were determined by differential scanning calorimetry and X-ray analysis, respectively. The difference in denaturation Gibbs energy (DeltaDeltaG) for the ten Gly to Ala mutants ranged from + 1.9 to -7.5 kJ/mol, indicating that the effect of the mutation depends on the environment of the residue. We confirm that Gly in a left-handed region is more favorable at rigid sites than non-Gly, but there is little difference in energetic cost between Gly and non-Gly at flexible sites. The present results indicate that dihedral angles in the backbone conformation and also the flexibility at the position should be considered for analyses of protein stability, and protein structural determination, prediction, and design.

PubMed: 11599030
DOI: 10.1002/prot.1147

Experimental method

X-RAY DIFFRACTION (1.8 Å)