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Formation of Poly[d(A-T)2] Specific Z-DNA by a Cationic Porphyrin.

ABSTRACT: Typical CD spectrum of the right-handed poly[d(A-T)2] was reversed when trans-bis(N-methylpyrimidium-4-yl)diphenyl porphyrin (trans-BMPyP) was bound, suggesting that the helicity of the polynucleotide was reversed to the left-handed form. The formation of the left-handed Z-form poly[d(A-T)2] was confirmed by (31)P NMR, in which a single (31)P peak of B-form poly[d(A-T)2] was split into two peaks, which is similar to the conventional B-Z transition of poly[d(G-C)2] induced by the high ionic strength. The observed B-Z transition is unique for poly[d(A-T)2]. The other polynucleotides, including poly[d(G-C)2], poly(dG)·poly(dC) and poly(dA)·poly(dT) remained as the right-handed form in the presence of the same porphyrin. This observation suggests that the porphyrin array that was formed along the poly[d(A-T)2] provides a template to which left-handed poly[d(A-T)2] is associated with an electrostatic interaction.

SUBMITTER: Jang YJ

PROVIDER: S-EPMC4421867 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Formation of Poly[d(A-T)2] Specific Z-DNA by a Cationic Porphyrin.

Jang Yoon Jung YJ Lee Changyun C Kim Seog K SK

Scientific reports 20150506

Typical CD spectrum of the right-handed poly[d(A-T)2] was reversed when trans-bis(N-methylpyrimidium-4-yl)diphenyl porphyrin (trans-BMPyP) was bound, suggesting that the helicity of the polynucleotide was reversed to the left-handed form. The formation of the left-handed Z-form poly[d(A-T)2] was confirmed by (31)P NMR, in which a single (31)P peak of B-form poly[d(A-T)2] was split into two peaks, which is similar to the conventional B-Z transition of poly[d(G-C)2] induced by the high ionic stren ...[more]

PMID: 25943171

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