View source for 1yfh

[[Image:1yfh.gif|left|200px]]<br />
<applet load="1yfh" size="450" color="white" frame="true" align="right" spinBox="true" 
caption="1yfh, resolution 3.01&Aring;" />
'''wt Human O6-Alkylguanine-DNA Alkyltransferase Bound To DNA Containing an Alkylated Cytosine'''<br />

==Overview==
O6-Alklyguanine-DNA alkyltransferase (AGT) is an important DNA repair, protein that protects cells from mutagenesis and toxicity arising from, alkylating agents. We present an X-ray crystal structure of the wild-type, human protein (hAGT) bound to double-stranded DNA with a chemically, modified cytosine base. The protein binds at two different sites: one at, the modified base, and the other across a sticky-ended DNA junction. The, protein molecule that binds the modified cytosine base flips the base and, recognizes it in its active site. The one that binds ends of neighboring, DNA molecules partially flips an overhanging thymine base. This base is, not inserted into the active-site pocket of the protein. These two, different hAGT/DNA interactions observed in the structure suggest that, hAGT may not detect DNA lesions by searching for the adduct itself, but, rather for weakened and/or distorted base-pairs caused by base damage in, the duplex DNA. We propose that hAGT imposes a strain on the DNA duplex, and searches for DNA regions where the native structure is destabilized., The structure provides implications for pyrimidine recognition, improved, inhibitor design, and a possible protein/protein interaction patch on, hAGT.

==About this Structure==
1YFH is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with ZN as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Methylated-DNA--[protein]-cysteine_S-methyltransferase Methylated-DNA--[protein]-cysteine S-methyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.1.1.63 2.1.1.63] Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1YFH OCA]. 

==Reference==
The structure of the human AGT protein bound to DNA and its implications for damage detection., Duguid EM, Rice PA, He C, J Mol Biol. 2005 Jul 22;350(4):657-66. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=15964013 15964013]
[[Category: Homo sapiens]]
[[Category: Methylated-DNA--[protein]-cysteine S-methyltransferase]]
[[Category: Single protein]]
[[Category: Duguid, E.M.]]
[[Category: He, C.]]
[[Category: Rice, P.A.]]
[[Category: ZN]]
[[Category: protein-dna complex]]

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