Denaturation urea-induced

Bennion BJ, Daggett V (2004) Counteraction of urea-induced protein denaturation by trimethylamine N-oxide a chemical chaperone at atomic resolution. Proc Natl Acad Sci USA 101 6433... 

Wang L, Colon W (2005) Urea-induced denaturation of apolipoprotein serum amyloid A reveals marginal stability of hexamer. Protein Sci 14 1811—1817... 

The other main application of FST to open systems has involved the study of preferential interactions. This is particularly important for understanding the effects of a cosolvent on the properties of biomolecules—the urea-induced denaturation of proteins, for example. The major source for thermodynamic data on small molecule binding to proteins has been equilibrium dialysis studies (Timasheff 1998a). More recently, this has been complemented by isopiestic distillation studies (Anderson, Courtenay, and Record 2002). Both approaches provide thermodynamic descriptions of cosolvent interactions with proteins that can be used to rationalize the effects of cosolvents on protein stability obtained from isothermal-isobaric studies (Smith 2004). 

Tanaka N, Nishizawa H, Kunugi S. Structure of pressure-induced denatured state of human serum albumin a comparison with the intermediate in urea-induced denaturation. Biochim Biophys Acta 1997 1338(l) 13-20. 

Figure 37.6 Effect of flavin cofactor binding on the stability of the human electron-transfer flavoprotein (ETF) mutant variant Aspl28Asn. (A) Activity of the protein is affected by incubation at 39 °C (open circles) however, in the presence of 2.5-fold excess FAD the activity is preserved (black circles). (B) The stability of ETF Aspl28Asn to urea-induced chemical denaturation is higher when the flavin is bound to the protein (black circles) than in flavin-depleted ETF (open circles). (C) The presence of flavin cofactor affects the proteolytic susceptibility of ETF Aspl28Asn. Upon incubation with trypsin protease ETF Aspl28Asn is rapidly degraded (top panel), whereas in the presence of excess flavin, the protein is more resistance to proteolysis.

M. C. Stumpe and H. Grubmuller, PLoS Comput. Biol., 4, el000221 (2008). Polar or Apolar-The Role of Polarity for Urea-Induced Protein Denaturation. 

Limited SAXS studies suggest that urea and GuHCl produce indistinguishable denatured states. For example, the unfolded states of apomyo-globin, creatine kinase, and the pI3K SH2 domain induced by urea... 

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