Structural highlights
Function[3MG2_ECOLI] Hydrolysis of the deoxyribose N-glycosidic bond to excise 3-methyladenine, 3-methylguanine, 7-methylguanine, O2-methylthymine, and O2-methylcytosine from the damaged DNA polymer formed by alkylation lesions. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedBase-excision DNA repair proteins that target alkylation damage act on a variety of seemingly dissimilar adducts, yet fail to recognize other closely related lesions. The 1.8 A crystal structure of the monofunctional DNA glycosylase AlkA (E. coli 3-methyladenine-DNA glycosylase II) reveals a large hydrophobic cleft unusually rich in aromatic residues. An Asp residue projecting into this cleft is essential for catalysis, and it governs binding specificity for mechanism-based inhibitors. We propose that AlkA recognizes electron-deficient methylated bases through pi-donor/acceptor interactions involving the electron-rich aromatic cleft. Remarkably, AlkA is similar in fold and active site location to the bifunctional glycosylase/lyase endonuclease III, suggesting the two may employ fundamentally related mechanisms for base excision. Structural basis for the excision repair of alkylation-damaged DNA.,Labahn J, Scharer OD, Long A, Ezaz-Nikpay K, Verdine GL, Ellenberger TE Cell. 1996 Jul 26;86(2):321-9. PMID:8706136[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences | ||||||||||||||||||||||
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