Peptide-induced parallel DNA duplexes for oligopyrimidines. Stereospecificity in complexation for oligo(L-lysine) and oligo(L-ornithine)

Journal Article · Tue Aug 28 00:00:00 EDT 1990 · Biochemistry; (USA)

DOI:https://doi.org/10.1021/bi00486a009· OSTI ID:6101730

van Genderen, M H.P.; Hilbers, M P; Koole, L H; Buck, H M ^[1]

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1. Eindhoven Univ. of Technology (Netherlands)

It is shown that the cationic oligopeptides octadeca(L-lysine) (Lys{sub 18}) and octadeca(L-ornithine) (Orn{sub 18}) can induce a parallel duplex for the natural DNA oligomer dT{sub 10} with thymine-thymine base pairs. Complexation of the ammonium groups in the peptide side chains with the DNA phosphates leads to diminished electrostatic phosphate-phosphate repulsions, which allows this T-T base pair formation. From combined NOESY {sup 1}H NMR and molecular mechanics studies, it follows that the parallel duplex is right-handed, with the peptide located in the groove of the duplex. For the natural DNA oligomers dC{sub 10}, d(C{sub 6}T{sub 6}), and d(T{sub 6}C{sub 2}T{sub 2}), only Lys{sub 18} is able to induce the formation of parallel duplexes with C-C and T-T base pairs. It is shown that, for Orn{sub 18}, a complexation must occur with one of the nonbonded oxygen atoms in the phosphate groups (Q{sub R}) in such a way that unfavorable steric interactions are present with the C-C base pairs, which have a larger propellor twist angle than T-T base pairs. An analogy is presented between peptide complexation with the phosphates and the neutralization of the phosphate groups by methylation, which is known to lead to parallel duplexes with T-T base pairs (for both the S{sub P} and R{sub P} configurations) and C-C base pairs (only for the S{sub P} configuration).

• OSTI ID: 6101730
• Journal Information: Biochemistry; (USA), Journal Name: Biochemistry; (USA) Vol. 29:34; ISSN 0006-2960; ISSN BICHA
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
AMINO ACIDS
AZINES
BARYONS
CARBOXYLIC ACIDS
CHEMICAL REACTIONS
CHEMICAL SHIFT
DNA
ELEMENTARY PARTICLES
FERMIONS
HADRONS
HETEROCYCLIC COMPOUNDS
LYSINE
MAGNETIC RESONANCE
MATHEMATICAL MODELS
METHYLATION
MOLECULAR MODELS
MOLECULAR STRUCTURE
NUCLEAR MAGNETIC RESONANCE
NUCLEIC ACIDS
NUCLEONS
OLIGONUCLEOTIDES
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OVERHAUSER EFFECT
PROTONS
PYRIMIDINES
RESONANCE
STEREOCHEMISTRY