Role of side-chains in the cooperative beta-hairpin folding of the short C-terminal fragment derived from streptococcal protein G.


Abstract

A short C-terminal fragment of immunoglobulin-binding domain of streptococcal protein G is known to form nativelike beta-hairpin at physiological conditions. To understand the cooperative folding of the short peptide, eight Ala-substituted mutants of the fragment were investigated with respect to their structural stabilities by analyzing temperature dependence of NMR signals. On comparison of the obtained thermodynamic parameters, we found that the nonpolar residues Tyr45 and Phe52 and the polar residues Asp46 and Thr49 are crucial for the beta-hairpin folding. The results suggest a strong interaction between the nonpolar side chains that participates in a putative hydrophobic cluster and that the polar side chains form a fairly rigid conformation around the loop (46-51). We also investigated the complex formation of the mutants with N-terminal fragment at the variety of temperature to get their thermal unfolding profiles and found that the mutations on the residues Asp46 and Thr49 largely destabilized the complexes, while substitution of Asp47 slightly stabilized the complex. From these results, we deduced that both the hydrophobic cluster formation and the rigidity of the loop (46-51) cooperatively stabilize the beta-hairpin structure of the fragment. These interactions which form a stable beta-hairpin may be the initial structural scaffold which is important in the early folding events of the whole domain. Study holds ProTherm entries: 8092, 8093, 8094, 8095, 8096, 8097, 8098, 8099, 8100, 8101, 8102 Extra Details: beta-hairpin; cooperative folding; hydrophobic cluster; rigid,conformation

Submission Details

ID: wCiJXjiS

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:35 p.m.

Version: 1

Publication Details
Kobayashi N;Honda S;Yoshii H;Munekata E,Biochemistry (2000) Role of side-chains in the cooperative beta-hairpin folding of the short C-terminal fragment derived from streptococcal protein G. PMID:10828973
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
1EM7 2000-03-16T00:00:00+0000 2.0 HELIX VARIANT OF THE B1 DOMAIN FROM STREPTOCOCCAL PROTEIN G
1GB1 1991-05-15T00:00:00+0000 0 A NOVEL, HIGHLY STABLE FOLD OF THE IMMUNOGLOBULIN BINDING DOMAIN OF STREPTOCOCCAL PROTEIN G
1IGC 1994-08-05T00:00:00+0000 2.6 IGG1 FAB FRAGMENT (MOPC21) COMPLEX WITH DOMAIN III OF PROTEIN G FROM STREPTOCOCCUS
1IGD 1994-08-05T00:00:00+0000 1.1 THE THIRD IGG-BINDING DOMAIN FROM STREPTOCOCCAL PROTEIN G: AN ANALYSIS BY X-RAY CRYSTALLOGRAPHY OF THE STRUCTURE ALONE AND IN A COMPLEX WITH FAB
1LE3 2002-04-09T00:00:00+0000 0 NMR Structure of Tryptophan Zipper 4: A Stable Beta-Hairpin Peptide Based on the C-terminal Hairpin of the B1 Domain of Protein G
1MPE 2002-09-12T00:00:00+0000 0 Ensemble of 20 structures of the tetrameric mutant of the B1 domain of streptococcal protein G
1MVK 2002-09-25T00:00:00+0000 2.5 X-ray structure of the tetrameric mutant of the B1 domain of streptococcal protein G
1PGA 1993-11-23T00:00:00+0000 2.07 TWO CRYSTAL STRUCTURES OF THE B1 IMMUNOGLOBULIN-BINDING DOMAIN OF STREPTOCOCCAL PROTEIN G AND COMPARISON WITH NMR
1PGB 1993-11-23T00:00:00+0000 1.92 TWO CRYSTAL STRUCTURES OF THE B1 IMMUNOGLOBULIN-BINDING DOMAIN OF STREPTOCCOCAL PROTEIN G AND COMPARISON WITH NMR
1PGX 1992-04-03T00:00:00+0000 1.66 THE 1.66 ANGSTROMS X-RAY STRUCTURE OF THE B2 IMMUNOGLOBULIN-BINDING DOMAIN OF STREPTOCOCCAL PROTEIN G AND COMPARISON TO THE NMR STRUCTURE OF THE B1 DOMAIN

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
100.0 Immunoglobulin G-binding protein G P06654 SPG1_STRSG
100.0 Immunoglobulin G-binding protein G P19909 SPG2_STRSG