4nig
From Proteopedia
Crystal structure of AlkB D135I/E136H mutant protein with cofactors bound to dsDNA containing m6A/A
Structural highlights
FunctionALKB_ECOLI Dioxygenase that repairs alkylated DNA and RNA containing 3-methylcytosine or 1-methyladenine by oxidative demethylation. Has highest activity towards 3-methylcytosine. Has lower activity towards alkylated DNA containing ethenoadenine, and no detectable activity towards 1-methylguanine or 3-methylthymine. Accepts double-stranded and single-stranded substrates. Requires molecular oxygen, alpha-ketoglutarate and iron. Provides extensive resistance to alkylating agents such as MMS and DMS (SN2 agents), but not to MMNG and MNU (SN1 agents).[1] [2] [3] [4] [5] [6] Publication Abstract from PubMedThe AlkB family demethylases AlkB, FTO, and ALKBH5 recognize differentially methylated RNA/DNA substrates, which results in their distinct biological roles. Here we identify key active-site residues that contribute to their substrate specificity. Swapping such active-site residues between the demethylases leads to partially switched demethylation activities. Combined evidence from X-ray structures and enzyme kinetics suggests a role of the active-site residues in substrate recognition. Such a divergent active-site sequence may aid the design of selective inhibitors that can discriminate these homologue RNA/DNA demethylases. Switching Demethylation Activities between AlkB Family RNA/DNA Demethylases through Exchange of Active-Site Residues.,Zhu C, Yi C Angew Chem Int Ed Engl. 2014 Apr 1;53(14):3659-62. doi: 10.1002/anie.201310050., Epub 2014 Mar 5. PMID:24596302[7] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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