Protein titration curve

Tanford, C., Kirkwood, J. G. Theory of protein titration curves. I. General equations for impenetrable spheres. J. Am. Chem. Soc. 79 (1957) 5333-5339. 6. Garrett, A. J. M., Poladian, L. Refined derivation, exact solutions, and singular limits of the Poisson-Boltzmann equation. Ann. Phys. 188 (1988) 386-435. Sharp, K. A., Honig, B. Electrostatic interactions in macromolecules. Theory and applications. Ann. Rev. Biophys. Chem. 19 (1990) 301-332. 

Tanford, C., Roxby, R. Interpretation of protein titration curves Application to lysozyme. Biochem. 11 (1972) 2192-2198. 

Tanford, C, Theory of Protein Titration Curves. 11. Calculations for Simple Models at Low Ionic Strength, Journal of the American Chemical Society 79, 5340, 1957. 

Tanford, C Roxy, Interpretation of Protein Titration Curves Application to Lysozyme, Biochemistry 11, 2192, 1972. 

Tanford C, Kirkwood JG (1957) Theory of protein titration curves. I. general equations for impenetrable spheres. J Am Chem Soc 79 5333—5339. 

In addition to the methods described above, the dependence of a protein titration curve on the salt concentration can also be exploited by making use of the ion step method. The essential aspect of this approach is, as with the previously de-... 

The relation between structure and acidity of organic compounds has been the subject of much study. Those aspects which are of interest in connection with protein titration curves have been reviewed in definitive manner by Edsall and Wyman (1958) and by Edsall (1943), and the reader is referred to these reviews for a discussion of the theoretical and empirical principles which are involved. For the present purpose it is sufficient to extract the data which will lead to the expected pK values of the titratable groups of proteins, and this has been done in Table I. 

The assumption that protein molecules do not have unique interactions absent in smaller molecules is of course naive. It is in fact untrue. Special interactions occur and upset the expectations with which this section has been concerned. It is the occurrence of such deviations from the expected result which lend interest and importance to the study of protein titration curves. 

Large sections of protein titration curves are often equally time-independent and reversible, as, for instance, the acid part of the titration curve of (3-lactoglobulin shown in Fig. 2. Any such section of the titration curve will again represent thermodynamic equilibrium and it may be subjected to thermodynamic analysis, as outlined in Sections VI and VII. 

A summary of information on the reversibility of protein titration curves,... 

The fact that a protein titration curve is reversible over a given range... 

Table V shows that the vast majority of the titratable groups of the smaller protein molecules have pK nt values which are quite close to the values predicted from the pK s of model compounds. This feature of protein titration curves has been well known for a long time, and is accepted as normal. It is however really an astonishing result, for it implies that most of the titratable groups of the smaller protein molecules are in as intimate contact with the solvent as similar groups on smaller molecules, and that they are able to accept or release hydrogen ions in this location without requiring any modification of the protein conformation in the vicinity of the titratable group. Since most of the proteins examined have been globular proteins, tightly folded so as to exclude solvent from most of the interior portions, the titratable groups must be nearly always at the surface.

The first detailed analysis of a protein titration curve, according to the semiempirical treatment used for most of the titration curves reviewed in this paper, also involves ovalbumin (Cannan el al., 1941). The first discovery of phenolic groups inaccessible to titration was again made with this protein (Crammer and Neuberger, 1943). 

In most protein titration curves, including the two examples already given, only two discrete steps are readily discernible, and it is difficult to pick out even from these the numbers and dissociation constants of sets of... 

K. Linderstrom-Lang, Compt. Rend. Trav. Lab. Carlsberg, 15, 1 (1924). The Ionization of Proteins. C. Tanford and J. G. Kirkwood, /. Am. Chem. Soc., 79, 5333 (1957). Theory of Protein Titration Curves. I. General Equations for Impenetrable Spheres. 

Interpretation of Protein Titration Curves. Application to Lysozyme. S. J. Shire,... 

This database allows for the upload, download and analysis of protein titration curves thus providing access to the primary experimental data produced by protein titration experiments. 

Since pairwise electrostatic interaction energies can be calculated from protein structures using Poisson-Boltzmann Equation (PBE) solvers [71,72], we can attempt to forge a unique link between protein structure and protein titration curves... 

Goming years will see fhe consfrucfion of more sophisticated methods for analyzing protein titration curves as outlined in the previous section, but there will... 

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