CUPRIC COMPLEXES OF POLY(L-LYSINE, L-TYROSINE) - SPECTROSCOPIC DETERMINATION OF STRUCTURE IN AQUEOUS-SOLUTION

The formation and structure of two Cu(II)-(L-Lys, L-Tyr)n complexes have been investigated using potentiometric, absorption, circular dichroism (CD), and resonance Raman measurements. Two complexes have been detected. The first, which is fully defined at pH 7.8, contains four nitrogens-two from amino groups of lateral chains and two from peptide groups-and a phenolate oxygen, presumably in apical position, bound to the metal. The second complex that forms at pH 11.6-12.2 contains a cupric ion coordinated to four peptide nitrogens. © 1979.