3qk4

</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=3qk4 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3qk4 OCA], [https://pdbe.org/3qk4 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3qk4 RCSB], [https://www.ebi.ac.uk/pdbsum/3qk4 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3qk4 ProSAT]</span></td></tr>

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== Publication Abstract from PubMed ==

We report the 2.6A resolution crystal structure of the tetra-decamer d(CGCGGGTACCCGCG) in the tetragonal space group P4(3). This sequence contains the KpnI restriction site GGTACC in the centre which is flanked by alternating 'CG' sequences, and has a 'TA' step at the centre. These are features could favour the left-handed Z type helix. Despite this, overall the molecule has the A form. This is the first tetra-decamer crystallized in the A-DNA conformation, i.e. more than one full turn of the A helix. The crystallographic asymmetric unit consists of one tetra-decamer duplex. The helical twist and slide, as well as the base pair-base pair stacking interactions show alternations at the alternating pyrimidine-purine and purine-pyrimidine base steps. This variation is reminiscent of the dinucleotide repeat in left-handed Z-DNA helices. The crystal packing is unlike other A-DNA crystal structures, with each helix having a large number of contacts of many different types with symmetry-related neighbours.

The structure of a full turn of an A-DNA duplex d(CGCGGGTACCCGCG)(2).,Venkadesh S, Mandal PK, Gautham N Biochem Biophys Res Commun. 2011 Apr 8;407(2):307-12. Epub 2011 Mar 21. PMID:21397589<ref>PMID:21397589</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>

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== References ==

<references/>

[[Category: Gautham, N]]

[[Category: Mandal, P K]]

[[Category: Venkadesh, S]]

[[Category: Dna]]