Contribution of hydrophobic residues to the stability of human lysozyme: calorimetric studies and X-ray structural analysis of the five isoleucine to valine mutants.


Abstract

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. Study holds ProTherm entries: 802, 803, 804, 805, 806, 807, 13422, 13423, 13424, 13425, 13426 Extra Details: protein stability; hydrophobicity; cavity; calorimetry; human lysozyme

Submission Details

ID: hA9haHZM4

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:15 p.m.

Version: 1

Publication Details
Takano K;Ogasahara K;Kaneda H;Yamagata Y;Fujii S;Kanaya E;Kikuchi M;Oobatake M;Yutani K,J. Mol. Biol. (1995) Contribution of hydrophobic residues to the stability of human lysozyme: calorimetric studies and X-ray structural analysis of the five isoleucine to valine mutants. PMID:7473760
Additional Information

Structure view and single mutant data analysis

Study data

No weblogo for data of varying length.
Colors: D E R H K S T N Q A V I L M F Y W C G P
 

Data Distribution

Studies with similar sequences (approximate matches)

Correlation with other assays (exact sequence matches)


Relevant PDB Entries

Structure ID Release Date Resolution Structure Title
133L 1993-06-01T00:00:00+0000 1.77 ROLE OF ARG 115 IN THE CATALYTIC ACTION OF HUMAN LYSOZYME. X-RAY STRUCTURE OF HIS 115 AND GLU 115 MUTANTS
134L 1993-06-01T00:00:00+0000 1.77 ROLE OF ARG 115 IN THE CATALYTIC ACTION OF HUMAN LYSOZYME. X-RAY STRUCTURE OF HIS 115 AND GLU 115 MUTANTS
1B5U 1999-01-11T00:00:00+0000 1.8 CONTRIBUTION OF HYDROGEN BONDS TO THE CONFORMATIONAL STABILITY OF HUMAN LYSOZYME: CALORIMETRY AND X-RAY ANALYSIS OF SIX SER->ALA MUTANT
1B5V 1999-01-11T00:00:00+0000 2.17 CONTRIBUTION OF HYDROGEN BONDS TO THE CONFORMATIONAL STABILITY OF HUMAN LYSOZYME: CALORIMETRY AND X-RAY ANALYSIS OF SIX SER->ALA MUTANTS
1B5W 1999-01-11T00:00:00+0000 2.17 CONTRIBUTION OF HYDROGEN BONDS TO THE CONFORMATIONAL STABILITY OF HUMAN LYSOZYME: CALORIMETRY AND X-RAY ANALYSIS OF SIX SER->ALA MUTANTS
1B5X 1999-01-11T00:00:00+0000 2.0 Contribution of hydrogen bonds to the conformational stability of human lysozyme: calorimetry and x-ray analysis of six ser->ala mutants
1B5Y 1999-01-11T00:00:00+0000 2.2 CONTRIBUTION OF HYDROGEN BONDS TO THE CONFORMATIONAL STABILITY OF HUMAN LYSOZYME: CALORIMETRY AND X-RAY ANALYSIS OF SIX SER->ALA MUTANTS
1B5Z 1999-01-11T00:00:00+0000 2.2 CONTRIBUTION OF HYDROGEN BONDS TO THE CONFORMATIONAL STABILITY OF HUMAN LYSOZYME: CALORIMETRY AND X-RAY ANALYSIS OF SIX SER->ALA MUTANTS
1B7L 1999-01-24T00:00:00+0000 1.8 VERIFICATION OF SPMP USING MUTANT HUMAN LYSOZYMES
1B7M 1999-01-24T00:00:00+0000 2.2 VERIFICATION OF SPMP USING MUTANT HUMAN LYSOZYMES

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
96.9 Lysozyme C P79180 LYSC_HYLLA
99.2 Lysozyme C P79239 LYSC_PONPY
100.0 Lysozyme C P61628 LYSC_PANTR
100.0 Lysozyme C P61627 LYSC_PANPA
100.0 Lysozyme C P61626 LYSC_HUMAN
100.0 Lysozyme C P79179 LYSC_GORGO