The transition state in the folding-unfolding reaction of four species of three-disulfide variant of hen lysozyme: the role of each disulfide bridge.


Abstract

The effects of lacking a specific disulfide bridge on the transition state in folding were examined in order to explore the folding-unfolding mechanism of lysozyme. Four species of three-disulfide variant of hen lysozyme (3SS-lysozyme) were prepared by replacing two Cys residues with Ala or Ser: C6S/C127A, C30A/C115A, C64A/C80A and C76A/C94A. The recombinant hen lysozyme was studied as the standard reference containing four authentic disulfide bridges and the extra N-terminal Met: the recombinant hen lysozyme containing the extra N-terminal. Folding rates were measured by monitoring the change in fluorescence intensity associated with tri-N-acetyl-d-glucosamine binding to the active site of refolded lysozyme. It was confirmed that the folding rate of the recombinant hen lysozyme containing the extra N-terminal was the same as that of wild-type lysozyme, and that the folding rate was little affected by the presence of tri-N-acetyl-d-glucosamine (triNAG). The folding rate of C64A/C80A was found to be the fastest and almost the same as that of the recombinant hen lysozyme containing the extra N-terminal, and that of C30A/C115A the second, and that of C6S/C127A the third. The folding rate of C76A/C94A was particularly slow. On the other hand, the unfolding rates which were measured in the presence of triNAG showed the dependence on the concentration of triNAG. The intrinsic unfolding rate in the absence of triNAG was determined by extrapolation. Also in the unfolding rate, C76A/C94A was markedly slower than the others. It was found from the analysis of binding constants of triNAG to C64A/C80A during the unfolding process that the active site of C64A/C80A partly unfolds already prior to the unfolding transition. On the basis of these kinetic data, we suggest that C64A/C80A folding transition can occur with leaving the loop region around SS3 (C64-C80) flexible, while cross-linking by SS4 (C76-C94) is important for the promotion of folding, because it is an indispensable constraint on the way towards the folding transition state. Study holds ProTherm entries: 8255, 8256, 8257, 8258, 8259, 8260, 8261, 8262, 8263, 8264, 8265, 8266, 8267, 8268 Extra Details: protein folding; lysozyme variants; disulfide bridge; transition state;,protein engineering

Submission Details

ID: BC5Eefn4

Submitter: Connie Wang

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

Version: 1

Publication Details
Yokota A;Izutani K;Takai M;Kubo Y;Noda Y;Koumoto Y;Tachibana H;Segawa S,J. Mol. Biol. (2000) The transition state in the folding-unfolding reaction of four species of three-disulfide variant of hen lysozyme: the role of each disulfide bridge. PMID:10653703
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
2IHL 1993-06-29T00:00:00+0000 1.4 LYSOZYME (E.C.3.2.1.17) (JAPANESE QUAIL)
1FBI 1995-01-19T00:00:00+0000 3.0 CRYSTAL STRUCTURE OF A CROSS-REACTION COMPLEX BETWEEN FAB F9.13.7 AND GUINEA-FOWL LYSOZYME
1GHL 1993-05-04T00:00:00+0000 2.1 THE THREE-DIMENSIONAL STRUCTURE OF PHEASANT AND GUINEA-FOWL EGG LYSOZYMES
1HHL 1993-05-04T00:00:00+0000 1.9 THE THREE-DIMENSIONAL STRUCTURE OF PHEASANT AND GUINEA-FOWL EGG LYSOZYMES
1JHL 1993-05-04T00:00:00+0000 2.4 THREE-DIMENSIONAL STRUCTURE OF A HETEROCLITIC ANTIGEN-ANTIBODY CROSS-REACTION COMPLEX
1BQL 1995-02-03T00:00:00+0000 2.6 STRUCTURE OF AN ANTI-HEL FAB FRAGMENT COMPLEXED WITH BOBWHITE QUAIL LYSOZYME
1DKJ 1996-01-10T00:00:00+0000 2.0 BOBWHITE QUAIL LYSOZYME
1DKK 1996-01-10T00:00:00+0000 1.9 BOBWHITE QUAIL LYSOZYME WITH NITRATE
135L 1993-06-10T00:00:00+0000 1.3 X-RAY STRUCTURE OF MONOCLINIC TURKEY EGG LYSOZYME AT 1.3 ANGSTROMS RESOLUTION
1DZB 2000-02-23T00:00:00+0000 2.0 Crystal structure of phage library-derived single-chain Fv fragment 1F9 in complex with turkey egg-white lysozyme

Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
92.3 Lysozyme C P49663 LYSC_PHAVE
93.0 Lysozyme C P81711 LYSC_SYRSO
93.2 Lysozyme C P00702 LYSC_PHACO
94.6 Lysozyme C P24533 LYSC_SYRRE
93.0 Lysozyme C P24364 LYSC_LOPLE
92.2 Lysozyme C P00704 LYSC_NUMME
95.2 Lysozyme C P00703 LYSC_MELGA
95.3 Lysozyme C Q7LZT2 LYSC_TRATE
95.3 Lysozyme C P22910 LYSC_CHRAM
96.1 Lysozyme C P19849 LYSC_PAVCR
95.3 Lysozyme C P00701 LYSC_COTJA
96.1 Lysozyme C Q7LZI3 LYSC_TRASA
96.9 Lysozyme C Q7LZP9 LYSC_LOPIM
96.9 Lysozyme C Q7LZQ0 LYSC_CATWA
96.9 Lysozyme C P00699 LYSC_CALCC
96.9 Lysozyme C P00700 LYSC_COLVI
100.0 Lysozyme C P00698 LYSC_CHICK