4ij0

<StructureSection load='4ij0' size='340' side='right' caption='[[4ij0]], [[Resolution|resolution]] 1.54&Aring;' scene=''>

<table><tr><td colspan='2'>[[4ij0]] is a 2 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4IJ0 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4IJ0 FirstGlance]. <br>

</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=HT:2-(4-HYDROXYPHENYL)-5-(4-METHYL-1-PIPERAZINYL)-2,5-BI-BENZIMIDAZOLE'>HT</scene>, <scene name='pdbligand=SR:STRONTIUM+ION'>SR</scene></td></tr>

<tr id='NonStdRes'><td class="sblockLbl"><b>[[Non-Standard_Residue|NonStd Res:]]</b></td><td class="sblockDat"><scene name='pdbligand=C6G:6-(CARBOXYMETHOXY)-9-(2-DEOXY-5-O-PHOSPHONO-BETA-D-ERYTHRO-PENTOFURANOSYL)-9H-PURIN-2-AMINE'>C6G</scene></td></tr>

<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[4itd|4itd]]</td></tr>

<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4ij0 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4ij0 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4ij0 RCSB], [http://www.ebi.ac.uk/pdbsum/4ij0 PDBsum]</span></td></tr>

<div style="background-color:#fffaf0;">

== Publication Abstract from PubMed ==

N-nitrosation of glycine and its derivatives generates potent alkylating agents that can lead to the formation of O6-carboxymethylguanine (O6-CMG) in DNA. O6-CMG has been identified in DNA derived from human colon tissue, and its occurrence has been linked to diets high in red and processed meats. By analogy to O6-methylguanine, O6-CMG is expected to be highly mutagenic, inducing G to A mutations during DNA replication that can increase the risk of gastrointestinal and other cancers. Two crystal structures of DNA dodecamers d(CGCG[O6-CMG]ATTCGCG) and d(CGC[O6-CMG]AATTCGCG) in complex with Hoechst33258 reveal that each can form a self-complementary duplex to retain the B-form conformation. Electron density maps clearly show that O6-CMG forms a Watson-Crick-type pair with thymine similar to the canonical A:T pair, and it forms a reversed wobble pair with cytosine. In situ structural modeling suggests that a DNA polymerase can accept the Watson-Crick-type pair of O6-CMG with thymine, but might also accept the reversed wobble pair of O6-CMG with cytosine. Thus, O6-CMG would permit the mis-incorporation of dTTP during DNA replication. Alternatively, the triphosphate that would be formed by carboxymethylation of the nucleotide triphosphate pool d[O6-CMG]TP might compete with dATP incorporation opposite thymine in a DNA template.

Structures of DNA duplexes containing O6-carboxymethylguanine, a lesion associated with gastrointestinal cancer, reveal a mechanism for inducing pyrimidine transition mutations.,Zhang F, Tsunoda M, Suzuki K, Kikuchi Y, Wilkinson O, Millington CL, Margison GP, Williams DM, Czarina Morishita E, Takenaka A Nucleic Acids Res. 2013 Apr 10. PMID:23580550<ref>PMID:23580550</ref>

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

</div>

== References ==

<references/>

[[Category: Millington, C L]]

[[Category: Morishita, E C]]

[[Category: Suzuki, K]]

[[Category: Takenaka, A]]

[[Category: Tsunoda, M]]

[[Category: Wilkinson, O]]

[[Category: Williams, D M]]

[[Category: Zhang, F]]

[[Category: O6-carboxymethylguanine]]