The denaturation temperatures and enthalpies of bovine pancreatic RNAase A in the presence of different amounts of D-glucose or its oligomers have been determined from DSC measurements and compared with literature results for other globular proteins in the presence of oligosaccharides or polyhydroxylated compounds. Both parameters increase almost proportionally for RNAase A at increasing sugar concentration (the denaturation appearing as a reversible, one-step process) and the evaluated Gibbs energy-temperature plots show an expansion of the stability range and an increase in relative stability. Isothermal measurements were also obtained by dilution-flow calorimetry to determine the virial coefficients of the excess enthalpies for aqueous solutions of some model peptides (N-acetylamides of simple amino acids) in the presence of l M D-glucose. These results provide an insight into the role of sugars in preventing peptide-peptide interactions.
Conformational stability of proteins and peptide-peptide interactions in the presence of carbohydrates / G., BARONE G; DEL VECCHIO, POMPEA GIUSEPPINA GRAZIA; Giancola, Concetta; G., Notaro. - In: THERMOCHIMICA ACTA. - ISSN 0040-6031. - STAMPA. - 199:(1992), pp. 189-196. [10.1016/0040-6031(92)80262-U]
Conformational stability of proteins and peptide-peptide interactions in the presence of carbohydrates.
DEL VECCHIO, POMPEA GIUSEPPINA GRAZIA;GIANCOLA, CONCETTA;
1992
Abstract
The denaturation temperatures and enthalpies of bovine pancreatic RNAase A in the presence of different amounts of D-glucose or its oligomers have been determined from DSC measurements and compared with literature results for other globular proteins in the presence of oligosaccharides or polyhydroxylated compounds. Both parameters increase almost proportionally for RNAase A at increasing sugar concentration (the denaturation appearing as a reversible, one-step process) and the evaluated Gibbs energy-temperature plots show an expansion of the stability range and an increase in relative stability. Isothermal measurements were also obtained by dilution-flow calorimetry to determine the virial coefficients of the excess enthalpies for aqueous solutions of some model peptides (N-acetylamides of simple amino acids) in the presence of l M D-glucose. These results provide an insight into the role of sugars in preventing peptide-peptide interactions.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
