The involvement of the omega -NH2 terminal group of L-lysine and L-ornithine in the complexation of Cu(II) was investigated by means of potentiometry, calorimetry, UV-Vis and ESR. The thermodynamic parameters (DeltaG(0), DeltaH(0) and DeltaS(0)) obtained by combining the potentiometric and calorimetric data show that the two ligands complex copper(II) in a different manner, indicating that the omega -NH2 terminal group is involved in ornithine complexes only. UV-Vis and ESR spectra further support the involvement of ornithine omega -NH2 and provide details on the complexation geometries of the complexes of the two amino acids. (C) 2000 Elsevier Science B.V. All rights reserved.
Copper(II) complexes with L-lysine and L-ornithine: is the side-chain involved in the coordination? A thermodynamic and spectroscopic study
CONTINO, Annalinda;MACCARRONE, Giuseppe;
2000-01-01
Abstract
The involvement of the omega -NH2 terminal group of L-lysine and L-ornithine in the complexation of Cu(II) was investigated by means of potentiometry, calorimetry, UV-Vis and ESR. The thermodynamic parameters (DeltaG(0), DeltaH(0) and DeltaS(0)) obtained by combining the potentiometric and calorimetric data show that the two ligands complex copper(II) in a different manner, indicating that the omega -NH2 terminal group is involved in ornithine complexes only. UV-Vis and ESR spectra further support the involvement of ornithine omega -NH2 and provide details on the complexation geometries of the complexes of the two amino acids. (C) 2000 Elsevier Science B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.