Conversion of two-state to multi-state folding kinetics on fusion of two protein foldons.


Chymotrypsin inhibitor 2 (CI2) is the archetypal single-foldon protein that folds in simple two-state kinetics without the accumulation of a folding intermediate. To model the effects of fusion of single foldons to give a multi-foldon protein, we engineered a "double-CI2" protein, in which another CI2 polypeptide was inserted into the loop region of the parent CI2. CD and HSQC spectra demonstrated that while the double-CI2 protein adopted two kinds of native conformations, CI2-like structure was almost preserved in both the domains of double-CI2. In the folding kinetic studies, double-CI2 exhibited a remarkable rollover of the observed folding rates at low denaturant concentrations, indicating that double-CI2 accumulated a kinetic folding intermediate. The different folding mechanisms between WT-CI2 and double-CI2 support the present view that protein size or number of domains is an important determinant for formation of folding intermediates. Study holds ProTherm entries: 8431 Extra Details: CI2; foldon; folding intermediate; protein design

Submission Details

ID: NrriCgAz

Submitter: Connie Wang

Submission Date: April 24, 2018, 8:36 p.m.

Version: 1

Publication Details
Inaba K;Kobayashi N;Fersht AR,J. Mol. Biol. (2000) Conversion of two-state to multi-state folding kinetics on fusion of two protein foldons. PMID:10964571
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 UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
100.0 Subtilisin-chymotrypsin inhibitor-2A P01053 ICI2_HORVU
92.6 Subtilisin-chymotrypsin inhibitor-2A P08626 ICI3_HORVU