View source for 1pnn


==PEPTIDE NUCLEIC ACID (PNA) COMPLEXED WITH DNA==
<StructureSection load='1pnn' size='340' side='right'caption='[[1pnn]], [[Resolution|resolution]] 2.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1pnn]] is a 4 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1PNN OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1PNN FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.5&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CPN:2-AMINOETHYLGLYCINE-CARBONYLMETHYLENE-CYTOSINE'>CPN</scene>, <scene name='pdbligand=IPN:2-AMINOETHYLGLYCINE-CARBONYLMETHYLENE-5-IODOURACIL'>IPN</scene>, <scene name='pdbligand=TPN:2-AMINOETHYLGLYCINE-CARBONYLMETHYLENE-THYMINE'>TPN</scene></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=1pnn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1pnn OCA], [https://pdbe.org/1pnn PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1pnn RCSB], [https://www.ebi.ac.uk/pdbsum/1pnn PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1pnn ProSAT]</span></td></tr>
</table>
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== Publication Abstract from PubMed ==
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.

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<ref>PMID:8525381</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 1pnn" style="background-color:#fffaf0;"></div>
== References ==
<references/>
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</StructureSection>
[[Category: Large Structures]]
[[Category: Betts L]]
[[Category: Veal JM]]