title: Changes in the c.d. spectra of calf thymus DNA induced by sequential polypeptides in aqueous solutions. Part I.
abstract: Interactions of calf thymus DNA with sequential polypeptides were studied using c.d. spectroscopy in aqueous solutions. It was found that DNA structural alterations induced by sequential polypeptides (L-Arg-X-Gly)n (where X = L-Val, Leu, Ile, Nva, Nle) are modulated by the nature of the X residue. Thus, the polypeptide (L-Arg-L-Nva-Gly)n induced the 10.2B-DNA form, whereas the polypeptides (L-Arg-L-Ile-Gly)n having one methyl group less on the X residue side chain, did not provide any significant modification to the structure of DNA. The effect of ionic strength from 0.14 M NaCl (physiological value) to zero was also analysed on the basis of the observed c.d. changes and the degree of complexation in the DNA-polypeptides was estimated.
authors.affiliation: Department of Chemistry, University of Ioannina, Greece.
authors.forename: V
authors.initials: V
authors.lastname: Tsikaris
authors.forename: E
authors.initials: E
authors.lastname: Panou-Pomonis
authors.forename: C
authors.initials: C
authors.lastname: Sakarellos
authors.forename: M
authors.initials: M
authors.lastname: Sakarellos-Daitsiotis
authors.forename: M
authors.initials: M
authors.lastname: Marraud
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry*; D004563:Electrochemistry; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry*; D012996:Solutions; D013950:Thymus Gland / Q000378:metabolism
chemical_list: D010455:Peptides; D012996:Solutions; D004247:DNA