1yao: Difference between revisions
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|PDB= 1yao |SIZE=350|CAPTION= <scene name='initialview01'>1yao</scene>, resolution 1.8Å | |PDB= 1yao |SIZE=350|CAPTION= <scene name='initialview01'>1yao</scene>, resolution 1.8Å | ||
|SITE= | |SITE= | ||
|LIGAND= <scene name='pdbligand=NA:SODIUM ION'>NA</scene> | |LIGAND= <scene name='pdbligand=NA:SODIUM+ION'>NA</scene> | ||
|ACTIVITY= [http://en.wikipedia.org/wiki/Lysozyme Lysozyme], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.17 3.2.1.17] | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Lysozyme Lysozyme], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.17 3.2.1.17] </span> | ||
|GENE= HUMAN LYSOZYME WITH ILE 56 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens]) | |GENE= HUMAN LYSOZYME WITH ILE 56 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens]) | ||
|DOMAIN= | |||
|RELATEDENTRY= | |||
|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1yao FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1yao OCA], [http://www.ebi.ac.uk/pdbsum/1yao PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1yao RCSB]</span> | |||
}} | }} | ||
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==Overview== | ==Overview== | ||
In order to understand the contribution of hydrophobic residues to the conformational stability of human lysozyme, five Ile mutants (Ile --> Val) in the interior of the protein were constructed. The thermodynamic parameters characterizing the denaturation of these mutant proteins were determined by scanning calorimetry, and the three-dimensional structure of each mutant protein was solved at high resolution by X-ray crystallography. The thermodynamic analyses at 64.9 degrees C and at pH 2.7 revealed the following. (1) The stabilities of all the mutant proteins were decreased as compared with that of the wild-type protein. (2) The changes in the calorimetric enthalpies were larger than those in the Gibbs energies, and were compensated by entropy changes. (3) The destabilization mechanism of the mutant proteins differs, depending on the location of the mutation sites. X-ray analyses showed that the overall structures of all the mutant human lysozymes examined were identical to that of the wild-type protein, and only small structural rearrangements were observed locally around some of the mutation sites. The most striking change among the mutant proteins was found in the mutant protein, 159V, which contains a new water molecule in the cavity created by the mutation. The thermodynamic stabilities of the mutant proteins are discussed in light of the high-resolution X-ray structures of the wild-type and five mutant human lysozymes examined. | In order to understand the contribution of hydrophobic residues to the conformational stability of human lysozyme, five Ile mutants (Ile --> Val) in the interior of the protein were constructed. The thermodynamic parameters characterizing the denaturation of these mutant proteins were determined by scanning calorimetry, and the three-dimensional structure of each mutant protein was solved at high resolution by X-ray crystallography. The thermodynamic analyses at 64.9 degrees C and at pH 2.7 revealed the following. (1) The stabilities of all the mutant proteins were decreased as compared with that of the wild-type protein. (2) The changes in the calorimetric enthalpies were larger than those in the Gibbs energies, and were compensated by entropy changes. (3) The destabilization mechanism of the mutant proteins differs, depending on the location of the mutation sites. X-ray analyses showed that the overall structures of all the mutant human lysozymes examined were identical to that of the wild-type protein, and only small structural rearrangements were observed locally around some of the mutation sites. The most striking change among the mutant proteins was found in the mutant protein, 159V, which contains a new water molecule in the cavity created by the mutation. The thermodynamic stabilities of the mutant proteins are discussed in light of the high-resolution X-ray structures of the wild-type and five mutant human lysozymes examined. | ||
==About this Structure== | ==About this Structure== | ||
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[[Category: Yamagata, Y.]] | [[Category: Yamagata, Y.]] | ||
[[Category: Yutani, K.]] | [[Category: Yutani, K.]] | ||
[[Category: hydrolase]] | [[Category: hydrolase]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Mar 31 01:00:56 2008'' | ||