SynopsisStatistical copolymers (LysZ,Alav), were synthesized by copolymerization of A:carboxyanhydrides of >amino acids. The conformation of copolymers in aqueous solutions was investigated using circular dichroism (Cl)). Calculations based on the CI) data showed that polymers (Lys=,Alav), can exhibit a random conformation, an 01helix, and a p-structure in various ratios. CD spectra of complexes of copolymers with DNA prepared by gradual dialysis from a high ionic strength to 0.15 N NaCl can be correlated with the copolymer conformation in medium and high ionic strength. For copolymers forming an a-helix and p-structure, these spectra show resemblance with similar spectra of complexes of t,hose histones that are able to exhibit ordered conformations.