title: [Attachment of trivaline changes the specificity of binding of netropsin analogs with DNA].
abstract: In the present communication, synthesis and DNA binding activities of three analogs of the antibiotic netropsin are reported. Each analog contains two N-propylpyrrolecarboxamide units linked covalently to either Dns-Gly-Val-Val-Val-Gly-Gly- (I), Val-Val-Val-Gly-Gly (II) or Gly-Gly (III). It is shown that analogs I and II can self-associate in aqueous solution and methanol as revealed from the fact that UV absorbance and circular dichroism spectra obtained for these analogs are concentration-dependent. By contrast, analogs III exists as a monomer, even at concentration levels of the order of 1.10(-3) M. Determination of the apparent sizes of intramolecular aggregates by gel-filtration shows that analog I in aqueous solution at concentration levels of the order of 1.10(-3) M forms a series of aggregates containing from 2 to 12 monomers. Analog II exhibits a lower tendency to form intermolecular aggregates as compared with that of analog I. Dimerization constants are determined for analogs I and II in aqueous solution and methanol. The binding of N-propylpyrrolecarboxamide units and peptide fragments of analog I to DNA can be independently monitored by circular dichroism and fluorescence methods. If self-associated species of analog I (or II) are present in solution, the ligand exhibits a markedly different order of base pair sequence preferencies as compared with that of analog III. The results obtained are consistent with the inference that analogs I and II in a beta-associated form recognizes base pair sequences containing two runs of 3 AT pairs separated by two GC pairs.
authors.forename: T A
authors.initials: TA
authors.lastname: Leĭnsoo
authors.forename: V A
authors.initials: VA
authors.lastname: Nikolaev
authors.forename: S L
authors.initials: SL
authors.lastname: Grokhovskiĭ
authors.forename: S A
authors.initials: SA
authors.lastname: Strel'tsov
authors.forename: A S
authors.initials: AS
authors.lastname: Zasedatelev
mesh_terms: D001483:Base Sequence; D001665:Binding Sites; D004247:DNA / Q000378:metabolism*; D006146:Guanidines / Q000378:metabolism*; D046911:Macromolecular Substances; D009429:Netropsin / Q000031:analogs & derivatives / Q000378:metabolism*; D013329:Structure-Activity Relationship; D014633:Valine
chemical_list: D006146:Guanidines; D046911:Macromolecular Substances; D009429:Netropsin; D004247:DNA; D014633:Valine
vernacular_title: Prisoedinenie trivalina izmeniaet spetsifichnost' sviazyvaniia analoga netropsina s DNK.