Journal Articles (before-1995)

Permanent URI for this collectionhttp://localhost:4000/handle/123456789/16938

Browse

Search Results

Now showing 1 - 2 of 2
  • Item
    Enthalpy of interaction between some cationic polypeptides and n-alkyl sulphates in aqueous solution
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1978, 74 (09-12), 1978) Paz-Andrade, Maria I.; Jones, Malcolm N.; Skinner, Henry A.
    The enthalpies of interaction of a homologous series of n-alkyl sulphates with poly(L-lysine)-hydrobromide, poly(L-arginine)hydrochloride and poly(L-histidine)hydrochloride have been measured at 25°C. A linear relationship between the enthalpy of interaction and carbon chain length has been found for alkyl chain lengths above C8. The data support a model based on a stoichiometric interaction between the anionic head group of the n-alkyl sulphates and the cationic side chains of the polypeptides. The results are discussed in relation to the interaction between surfactants and proteins, and lead to the view that a major contribution to the enthalpy of interaction arises from the surfactant–cationic residue interactions, but that there remains an additional contribution from surfactant–apolar aminoacid residue interactions.
  • Item
    Enthalpy of Interaction between some Globular Proteins and Sodium n-Dodecyl Sulphate in Aqueous Solution
    (Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1974, 70 (07), 1974) Tipping, Edward; Jones, Malcolm N.; Skinner, Henry A.
    The enthalpy of binding of sodium n-dodecyl sulphate (SDS) to scrum albumin, ovalbumin and ribonuclease A has been measured by microcalorimetry over the temperature range 18.5 to 32.0 C. The amount of SDS bound to the proteins has been measured over a wide range of SDS concentration by equilibrium dialysis. Changes in protein conformation have been monitored by viscometry. The results are consistent with a mechanism in which SDS binds initially to ionic sites on the protein molecules and initiates chain unfolding. At high binding levels the interaction is predominantly of a hydrophobic nature.