An analysis of the folding of the 94 residue tenth fibronectin type III (fnIII) domain of human fibronectin (FNfn10) is presented. Use of guanidine isothiocyanate as a denaturant allows us to obtain equilibrium and kinetic data across a broad range of denaturant concentrations that are unavailable in guanidine hydrochloride. Equilibrium unfolding experiments show that FNfn10 is significantly more stable than has been reported previously. Comparison of equilibrium and kinetic parameters reveals the presence of an intermediate that accumulates at low denaturant concentrations. This is the first demonstration of three-state folding kinetics for a fnIII domain. We have previously shown that a homologous domain from human tenascin (TNfn3) folds by a two-state mechanism, but this does not necessarily indicate that the two proteins fold by different folding pathways. Study holds ProTherm entries: 8084, 8085, 8086 Extra Details: FNfn10; tenth fnIII domain of fibronectin
Submitter: Connie Wang
Submission Date: April 24, 2018, 8:35 p.m.
|Number of data points||9|
|Proteins||Ribonuclease ; Fibronectin ; Tenascin ; Tenascin ; Ribonuclease ; Fibronectin|
|Assays/Quantities/Protocols||Experimental Assay: Cm pH:6.3 ; Experimental Assay: m pH:6.3 ; Experimental Assay: dG_H2O pH:6.3 ; Experimental Assay: Cm pH:5.0 ; Experimental Assay: m pH:5.0 ; Experimental Assay: dG_H2O pH:5.0|
|Libraries||Mutations for sequence RLDAPSQIEVKDVTDTTALITWFKPLAEIDGIELTYGIKDVPGDRTTIDLTEDENQYSIGNLKPDTEYEVSLISRRGDMSSNPAKETFTT ; Mutations for sequence VSDVPRDLEVVAATPTSLLISWDAPAVTVRYYRITYGETGGNSPVQEFTVPGSKSTATISGLKPGVDYTITVYAVTGRGDSPASSKPISINYRT ; Mutations for sequence AQVINTFDGVADYLQTYHKLPDNYITKSEAQALGWVASKGNLADVAPGKSIGGDIFSNREGKLPGKSGRTWREADINYTSGFRNSDRILYSSDWLIYKTTDHYQTFTKIR|