Proton Conductivity of Hydrated Lysozyme Powders, Considered Within the Framework of Percolation Theory

  • G. Careri
  • John A. Rupley


How does water at the surface of proteins enter into or modulate biochemical processes, particularly enzyme catalysis? This and other major questions about protein hydration remain open. We have approached such problems through study of the effect of change in water content on the thermodynamic and dynamic properties of protein powders. The advantage of this system is that the water activity (the hydration level) can be varied from zero (dry protein) to unity (dilute aqueous solution of protein). Thus the changes in chemistry and physics induced by hydration can be examined sequentially by comparison of samples of increasing level of hydration. Unravelling the complexity of hydration then becomes somewhat easier.


Percolation Threshold Proton Conductivity Percolation Theory Percolation Model Hydration Level 


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Copyright information

© Plenum Press, New York 1986

Authors and Affiliations

  • G. Careri
    • 1
  • John A. Rupley
    • 2
  1. 1.Dipartimento di FisicaUniversita di Roma IRomaItaly
  2. 2.University Department of BiochemistryUniversity of ArizonaTucsonUSA

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