Biochemistry denaturing proteins

Reflect and Apply A biochemistry student characterizes the process of cooking meat as an exercise in denaturing proteins. Comment on the validity of this remark. 

Schwalbe H, Fiebig KM, Buck M, Jones JA, Grimshaw SB, Spencer A, Glaser SJ, Smith LJ, Dobson CM (1997) Stmctural and dynamical properties of a denatured protein. Heteronuclear 3D NMR experiments and theoretical simulations of lysozyme in 8 M urea. Biochemistry 36 8977-8991... 

Figure 25.28 Pressure can denature proteins, ribonuclease A in this case. Source J Zhang, X Peng, A Jones and J Jones, Biochemistry 34, 8631-8641 (1995).

Ward, W. W., and Bokman, S. H. (1982). Reversible denaturation of Aequorea green-fluorescent protein physical separation and characterization of the renatured protein. Biochemistry 21 4535-4540. 

Heering, H.A., Bulsink, Y.B.M., Hagen, W.R., and Meyer, T.E. 1995. Reversible superreduction of the cubane [4Fe-4S](3+ 2+ 1+) in the high-potential iron-sulfur protein under non-denaturing conditions EPR spectroscopic and electrochemical studies. European Journal of Biochemistry 232 811-817. 

Lepock, J.R., K.P. Ritchie, M.C. Kolios, A.M. Rodahl, K.A. Heinz, and J. Kruuv. 1992. Influence of transition rates and scan rate on kinetic simulations of differential scanning calorimetry profiles of reversible and irreversible protein denaturation. Biochemistry 31 12706-12712. 

Anderson, D.K., BecktefW.J. and Dahlquist, F.W. (1990) pH-Induced Denaturation of Proteins A single Salt Bridge Contributes 3-5Kcal/mol to the Free Energy of Folding of T4 Lysozyme. Biochemistry, 29,2403-2408. 

There has been considerable effort on the prediction of secondary and tertiary structures of protein from the amino acid sequence using computeraided minimal potential energy calculations8). The question as to how a primary amino acid sequence begins to produce secondary and super-secondary structures and fold into its equilibrium tertiary structure and functional domains is a very active field of structural biochemistry. A related problem is the mechanism by which a protein unfolds or denatures 20) which is of fundamental interest in the protein adsorption process. 

Wang, A., and D.W. Bolen (1997). A naturally occurring protective system in urea-rich cells Mechanism of osmolyte protection of proteins against urea denaturation. Biochemistry 36 9101-9108. 

H. Qian, S. L. Mayo, and A. Morton. Protein hydrogen exchange in denaturant quantitative analysis a two-process model. Biochemistry, 33 8167-8171, 1994. 

In this report, these concepts are applied to real proteins to collagen, an important structural material in tendons, bones, teeth, and skin, and to gelatin, the denatured product of collagen that is so important industrially. These materials are complex because of their 18 different, component amino acid side chains in addition, they present experimental difficulties because of their water solubility— they cannot be washed (e.g., with an aqueous detergent) to assure surface cleanliness. Furthermore, they are often of unknown purity. They do have the common polyamide backbone, and it is possible to transform the molecular configuration. The data are indicative of the potential utility of contact angle measurements of important, natural materials. No claim is made for adequate attention to the complex biochemistry of these materials. 

Kim, K.-S. Woodward, C. (1993). Protein internal flexibility and global stability Effect of urea on hydrogen exchange rates of bovine pancreatic trypsin inhibitor. Biochemistry 32,9609-9613. Kuwajima, K., Nitta, K., Yoneyama, M. Sugai, S. (1976). Three-state denaturation of o-lactalbumin by guanidine hydrochloride. J. Mol. Biol. 106, 359-373. 

Brandts, J. F., Halverson, H. R., and Brennan, M. Consideration of the possibility that the slow step in protein denaturation reactions is due to cis-trans isomerism of proline residues. Biochemistry 14, 4953-4963 (1975). 

Timasheff, S. N. 1992. Water as ligand preferential binding and exclusion of denaturants in protein unfolding. Biochemistry. 31 ... 

Sidekari, V. Gilbert, H.F. Mechanism of the antichaperone activity of protein disulphide isomerase facilitated assembly of large, insoluble aggregates of denatured lysozyme and PDF Biochemistry 2000, 39, 1180-1188. 

Harding MM, Williams DH, and Woolfson DN. Characterization of a Partially Denatured State of a Protein by Two-dimensional NMR Reduction of the Hydrophobic Interactions in Ubiquitin. Biochemistry 1991 30 3120— 3128. 

Narhi LO, Philo JS, Li T, Zhang M, Samal B, and Arakawa T. Induction of a-helix in the (3-sheet Protein Tumor Necrosis Factor-a Thermal and Trifluo-roethanol Induced Denaturation at Neutral pH., Biochemistry 1996 35 11447-11453. 

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