Lysozyme hydrogen exchange

Fig. 22. Hydration dependence of amide hydrogen exchange in lysozyme powder at pH 5. Individual samples of pH 5 fully labeled (with H O) lysozyme were equilibrated at 25°C for 24 hr at various water contents obtained by isopiestic equilibration ( ) or by the addition and mixing of solvent (A). The samples were then dissolved to a concentration of 20 mg/ml and 100-/U.1 aliquots were analyzed by gel filtration. The arrow indicates the 24-hr solution H . end point. H, represents the number of hydrogens remaining unexchanged. From Schinkel el al. (1985).

Fig. 23. Dependence on log water activity of log ratio of powder to solution amide hydrogen exchange rate for lysozyme. Log rate ratio data for pH 2 (bottom) to pH 10 (top) are given as a function of log(/ /Po). The slopes of the lines give the order of the protein exchange reaction with respect to water. The slopes from least-squares linear regression are the following pH 2, 2.57 pH 3, 2.90 pH 5, 3.14 pH 7, 3.14 and pH 10, 2.53. Displacement along the log rate ratio axis is arbitrary. Numbers indicate some of the H m values for which rate ratios were determined. From Schinkel et at. (1985).

Fig. 30. Comparison of ESR and enzyme activity changes with hydration. Effect of hydration on lysozyme dynamic properties. (Curve f) Log rate of peptide hydrogen exchange. (Curve g) , Enzyme activity (log uo) O, rotational relaxation time (log t ) of the ESR probe TEMPONE. From Rupley et al. (1983).

Hilser, V. J. Freire, E. (1996b). Structure based calculation of the equilibrium folding pathway of proteins. Correlation with hydrogen exchange protection factors. J. Mol. Biol In Press. Hilser, V. J. Freire, E. (1996c). Structure-Based Statistical Thermodynamic Analysis of T4 Lysozyme Mutants Structural Mapping of Cooperative Interactions. Biophysical Chem.. ... 

Radford, S. E., Buck, M., Topping, K. D., Dobson, C. M. Evans, P. A. (1992a). Hydrogen exchange in native and denatured states of hen egg-white lysozyme. Proteins 14, 237-248. Radford, S. E., Dobson, C. M. Evans, P. A. (1992b). The Folding of Hen Lysozyme Involves Partially Structured Intermediates and Multiple Pathways. Nature 358, 302-307. 

Vogtt, K., Winter, R. Pressure-assisted cold denaturation of hen egg white lysozyme the influence of cosolvents probed by hydrogen exchange NMR, Braz. J. Med. Biol. Res. 38 (2005) 1185—1193. 

Stevens et al. (1964) have studied the effect of radiation on the enzymatic activity and hydrogen-exchange characteristics of lysozyme. Upon irradiation lysozyme lost its enzymatic activity at half the rate of loss of hard-to-exchange amide hydrogens, indicating that only half the native conformation of lysozyme is essential for activity. 

Bieri, O., Kiefhaber, T. (2001) Origin of apparent fast and non-exponential kinetics of lysozyme folding measured in pulsed hydrogen exchange experiments. Journal of Molecular Biology, 310 (4), 919-935. 

Scfainkel, J.E., Downer, N.W., Rupley, J.A. (1985) Hydrogen exchange of lysozyme powders. Hydration dependence of internal motions. Biochemistry, 24 (2), 352—366. 

Figure 33 Plot of the molecular mass versus temperature for the unfolding of hen egg white lysozyme (HEWL) (A) and horse heart myoglobin (HMYO) (B) at different temperatures utilizing the hydrogen exchange approach. In this...

Precise data on the kinetics of hydrogen-exchange for lysozyme have been obtained at pH 6.8 in the presence or absence of 2-acetamido-2-deoxy-D-glucose, which acts as an inhibitor. ... 

Internal dynamics of biomolecules is practically frozen without water. Upon increasing hydration level, it develops in a stepwise fashion [508]. At h K 0.15 g/g, internal protein motion, monitored by hydrogen exchange, achieves its solution rate [509]. Full internal dynamics of lysozyme is restored at /t 0.38 g/g [510]. Mossbauer spectroscopy studies evidence restoration of the internal dynamics of lysozyme... 

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