Document Type
Article
Publication Date
2021
Keywords
Protein Folding, Two-state Model, Size Scaling, Thermodynamic Cooperativity
Digital Object Identifier (DOI)
https://doi.org/10.3390/ijms22042184
Abstract
The coil to globule transition of the polypeptide chain is the physical phenomenon behind the folding of globular proteins. Globular proteins with a single domain usually consist of about 30 to 100 amino acid residues, and this finite size extends the transition interval of the coil-globule phase transition. Based on the pedantic derivation of the two-state model, we introduce the number of amino acid residues of a polypeptide chain as a parameter in the expressions for two cooperativity measures and reveal their physical significance. We conclude that the ๐2 measure, defined as the ratio of van โt Hoff and calorimetric enthalpy is related to the degeneracy of the denatured state and describes the number of cooperative units involved in the transition; additionally, it is found that the widely discussed ๐2=1 is just the necessary condition to classify the protein as the two-state folder. We also find that ฮฉ๐ , a quantity not limited from above and growing with system size, is simply proportional to the square of the transition interval. This fact allows us to perform the classical size scaling analysis of the coil-globule phase transition. Moreover, these two measures are shown to describe different characteristics of protein folding.
Rights Information
This work is licensed under a Creative Commons Attribution 4.0 License.
Was this content written or created while at USF?
Yes
Citation / Publisher Attribution
International Journal of Molecular Sciences, v. 22, issue 4, art. 2184
Scholar Commons Citation
Badasyan, Artem; Valant, Matjaz; Grdadolnik, Joลพe; and Uversky, Vladimir N., "The Finite Size Effects and Two-state Paradigm of Protein Folding" (2021). Molecular Medicine Faculty Publications. 845.
https://digitalcommons.usf.edu/mme_facpub/845
