Structural basis for the difference in thermodynamic properties between the two cysteine proteinase inhibitors human stefins A and B.


Abstract

Homology modelling has been used to model stefin A based on the X-ray structure of stefin B. Several models have been produced by interactive modelling or positioning of the side chains by Monte Carlo procedure with simulated annealing. The quality of models was evaluated by calculation of the free energy of hydration, 3D-1D potential or buried area of surface accessibility. Stefin A is a thermostable protein, exhibiting a two-state denaturation, while stefin B denatures at a 40 degrees C lower temperature and forms a stable molten globule intermediate under mild denaturing conditions. From the tertiary structures, thermodynamic functions were predicted, conforming closely to the experimental calorimetric results. Polar and apolar buried areas of surface accessibility were obtained by structural deconvolution of the thermograms. It is suggested that the basic difference between the stefins is the domination of hydrophobic interaction in the stabilization of stefin B, which is due to its non-specific nature leading to the formation of a molten globule intermediate. Modelling of stefin A predicts increased numbers of hydrogen bonds which stabilize it and increase the cooperativity of its denaturation. Study holds ProTherm entries: 10933, 10934 Extra Details: cysteine proteinase inhibitor; homology modelling;,molten globule; structural thermodynamics; thermostability

Submission Details

ID: jNybB7eD3

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:41 p.m.

Version: 1

Publication Details
Jerala R;Zerovnik E;Lohner K;Turk V,Protein Eng. (1994) Structural basis for the difference in thermodynamic properties between the two cysteine proteinase inhibitors human stefins A and B. PMID:7809037
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
1STF 1993-04-21T00:00:00+0000 2.37 THE REFINED 2.4 ANGSTROMS X-RAY CRYSTAL STRUCTURE OF RECOMBINANT HUMAN STEFIN B IN COMPLEX WITH THE CYSTEINE PROTEINASE PAPAIN: A NOVEL TYPE OF PROTEINASE INHIBITOR INTERACTION
2OCT 2006-12-21T00:00:00+0000 1.4 Stefin B (Cystatin B) tetramer
4N6V 2013-10-14T00:00:00+0000 1.8 Partial rotational order disorder structure of human stefin B
1CYU 1995-08-24T00:00:00+0000 0 SOLUTION NMR STRUCTURE OF RECOMBINANT HUMAN CYSTATIN A UNDER THE CONDITION OF PH 3.8 AND 310K
1CYV 1995-08-24T00:00:00+0000 0 SOLUTION NMR STRUCTURE OF RECOMBINANT HUMAN CYSTATIN A UNDER THE CONDITION OF PH 3.8 AND 310K
1DVC 1996-02-26T00:00:00+0000 0 SOLUTION NMR STRUCTURE OF HUMAN STEFIN A AT PH 5.5 AND 308K, NMR, MINIMIZED AVERAGE STRUCTURE
1DVD 1996-02-26T00:00:00+0000 0 SOLUTION NMR STRUCTURE OF HUMAN STEFIN A AT PH 5.5 AND 308K, NMR, 17 STRUCTURES
1GD3 2000-09-08T00:00:00+0000 0 refined solution structure of human cystatin A
1GD4 2000-09-08T00:00:00+0000 0 SOLUTION STRUCTURE OF P25S CYSTATIN A
1N9J 2002-11-25T00:00:00+0000 0 Solution Structure of the 3D domain swapped dimer of Stefin A

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
100.0 Cystatin-A P01040 CYTA_HUMAN
98.6 E Papain P00784 PAPA1_CARPA
94.9 Cystatin-B Q862Z5 CYTB_MACFU
99.0 Cystatin-B Q8I030 CYTB_PANTR
100.0 Cystatin-B P60576 CYTB_PONPY
100.0 Cystatin-B P60575 CYTB_PANPA
100.0 Cystatin-B P04080 CYTB_HUMAN
100.0 Cystatin-B Q76LA0 CYTB_GORGO