Journal Articles (before-1995)
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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.Item Microcalorimetric studies: Enthalpies of formation of Cr(PF3)6 and Ni(PF3)4(Journal of the Chemical Society : Faraday Transaction - I. The Chemical Society, London. 1974, 70 (09), 1974) S. Brown, D. Lalage; Connor, Joseph A.; Skinner, Henry A.Measurements of the heats of iodination of hexakis(trifluorophosphine)chromium(0) and of tetrakis(trifluorophosphine)nickel(0) were carried out by high temperature microcalorimetry. Standard enthalpies of formation were derived: ΔH°f(Ni(PF3)4, liq)=–961.9 ± 3 kcal mol–1(–4025 ± 12 kJ mol–1), ΔH°f(Cr(PF3)6, c)=–1446.4 ± 4 kcal mol–1(–6052 ± 17 kJ mol–1). The mean bond dissociation energies, D(Ni—PF3) and D(Cr—PF3) were evaluated as 35.2 ± 0.8 and 25.5 ± 1 kcal mol–1 respectively; these values compare very closely with the values D(Ni—CO) and D(Cr—CO) in Ni(CO)4 and Cr(CO)6.