Structural highlights
Function
[MUG_ECOLI] Excises ethenocytosine and uracil, which can arise by alkylation or deamination of cytosine, respectively, from the corresponding mispairs with guanine in ds-DNA. It is capable of hydrolyzing the carbon-nitrogen bond between the sugar-phosphate backbone of the DNA and the mispaired base. The complementary strand guanine functions in substrate recognition. Required for DNA damage lesion repair in stationary-phase cells.[1] [2]
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 PubMed
G:U mismatches resulting from deamination of cytosine are the most common promutagenic lesions occurring in DNA. Uracil is removed in a base-excision repair pathway by uracil DNA-glycosylase (UDG), which excises uracil from both single- and double-stranded DNA. Recently, a biochemically distinct family of DNA repair enzymes has been identified, which excises both uracil and thymine, but only from mispairs with guanine. Crystal structures of the mismatch-specific uracil DNA-glycosylase (MUG) from E. coli, and of a DNA complex, reveal a remarkable structural and functional homology to UDGs despite low sequence identity. Details of the MUG structure explain its thymine DNA-glycosylase activity and the specificity for G:U/T mispairs, which derives from direct recognition of guanine on the complementary strand.
Crystal structure of a G:T/U mismatch-specific DNA glycosylase: mismatch recognition by complementary-strand interactions.,Barrett TE, Savva R, Panayotou G, Barlow T, Brown T, Jiricny J, Pearl LH Cell. 1998 Jan 9;92(1):117-29. PMID:9489705[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Gallinari P, Jiricny J. A new class of uracil-DNA glycosylases related to human thymine-DNA glycosylase. Nature. 1996 Oct 24;383(6602):735-8. PMID:8878487 doi:http://dx.doi.org/10.1038/383735a0
- ↑ O'Neill RJ, Vorob'eva OV, Shahbakhti H, Zmuda E, Bhagwat AS, Baldwin GS. Mismatch uracil glycosylase from Escherichia coli: a general mismatch or a specific DNA glycosylase? J Biol Chem. 2003 Jun 6;278(23):20526-32. Epub 2003 Mar 31. PMID:12668677 doi:http://dx.doi.org/10.1074/jbc.M210860200
- ↑ Barrett TE, Savva R, Panayotou G, Barlow T, Brown T, Jiricny J, Pearl LH. Crystal structure of a G:T/U mismatch-specific DNA glycosylase: mismatch recognition by complementary-strand interactions. Cell. 1998 Jan 9;92(1):117-29. PMID:9489705
