The interaction between D- and L-enantiomers of polylysine and potassium pectate was studied by means of CD, microcalorimetry, and osmometry. Upon binding with pectate, only poly(L-lysine) undergoes a coil to α-helix transition, while poly(D-lysine) remains in the disordered state. This suggest that the energetics of the interaction is influenced by stereochemical constraints besides electrostatic forces. Experimental findings from microcalorimetry suggest that a contribution to the overall enthalpy of binding comes from the polysaccharidic moiety. Stoichiometry of the macromolecular complexes studied by osmometry gives a polylysine : pectate ratio of 3 : 1, in agreement with the respective degree of polymerization of the two polyelectrolytes
Paradossi, G., Chiessi, E., Malovikova, A. (1999). Study of the Interactions of D- and L- Polylysine Enantiomers with Pectate in Aqueous Solutions. BIOPOLYMERS, 50, 201-209 [10.1002/(SICI)1097-0282(199908)50:2<201::AID-BIP9>3.0.CO;2-Y].
Study of the Interactions of D- and L- Polylysine Enantiomers with Pectate in Aqueous Solutions
PARADOSSI, GAIO;CHIESSI, ESTER;
1999-01-01
Abstract
The interaction between D- and L-enantiomers of polylysine and potassium pectate was studied by means of CD, microcalorimetry, and osmometry. Upon binding with pectate, only poly(L-lysine) undergoes a coil to α-helix transition, while poly(D-lysine) remains in the disordered state. This suggest that the energetics of the interaction is influenced by stereochemical constraints besides electrostatic forces. Experimental findings from microcalorimetry suggest that a contribution to the overall enthalpy of binding comes from the polysaccharidic moiety. Stoichiometry of the macromolecular complexes studied by osmometry gives a polylysine : pectate ratio of 3 : 1, in agreement with the respective degree of polymerization of the two polyelectrolytesI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
