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1pnn

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Revision as of 20:02, 30 March 2008 by OCA (Talk | contribs)

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Image:1pnn.gif

, resolution 2.5Å

Ligands:

, , , ,

Resources:

FirstGlance, OCA, PDBsum, RCSB

Coordinates:

save as pdb, mmCIF, xml

PEPTIDE NUCLEIC ACID (PNA) COMPLEXED WITH DNA

Overview

The crystal structure of a nucleic acid triplex reveals a helix, designated P-form, that differs from previously reported nucleic acid structures. The triplex consists of one polypurine DNA strand complexed to a polypyrimidine hairpin peptide nucleic acid (PNA) and was successfully designed to promote Watson-Crick and Hoogsteen base pairing. The P-form helix is underwound, with a base tilt similar to B-form DNA. The bases are displaced from the helix axis even more than in A-form DNA. Hydrogen bonds between the DNA backbone and the Hoogsteen PNA backbone explain the observation that polypyrimidine PNA sequences form highly stable 2:1 PNA-DNA complexes. This structure expands the number of known stable helical forms that nucleic acids can adopt.

About this Structure

1PNN is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.

Reference

A nucleic acid triple helix formed by a peptide nucleic acid-DNA complex., Betts L, Josey JA, Veal JM, Jordan SR, Science. 1995 Dec 15;270(5243):1838-41. PMID:8525381

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