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PubMed · 9619506

Distamycin-stabilized antiparallel-parallel combination (APC) DNA.

A K Shchyolkina·L E Minchenkova·E E Minyat·Y B Khomyakova·V I Ivanov·R Klement·T M Jovin
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Abstract

The formation of Antiparallel-Parallel-Combination (APC) DNA, a liner duplex with a segment of parallel-stranded (ps) helix flanked by conventional B-DNA, was tested with a number of synthetic oligonucleotides. The groove-binding ligand distamycin A (DstA) was used to stabilize the ps segment comprising five A x T base pairs. Two drug molecules bound per APC, one in each of the two equivalent grooves characteristic of ps-DNA. APC-DNA, reference molecules and their complexes with DstA were analysed by several methods: circular dichroism and absorption spectroscopy, thermal denaturation, chemical modification, and molecular modeling. The dye binding stoichiometry differed significantly due to inherent structural differences in the groove geometries of ps-DNA (trans base pairs, similar grooves) and conventional antiparallel-stranded (aps) B-DNA (cis base pairs, distinct major and minor grooves). The data support the existence of APC folding in solution.

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Circular DichroismDNADistamycinsHeatingModels, MolecularNucleic Acid ConformationNucleic Acid DenaturationNucleic Acid HeteroduplexesOligodeoxyribonucleotidesJournal ArticleResearch Support, Non-U.S. Gov't

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A K Shchyolkina, L E Minchenkova, E E Minyat, Y B Khomyakova, V I Ivanov, R Klement, T M Jovin. 1998. Distamycin-stabilized antiparallel-parallel combination (APC) DNA.. https://doi.org/10.1080/07391102.1998.10508205

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