PMID:17588829
| Citation |
Srinath, T, Bharti, SK and Varshney, U (2007) Substrate specificities and functional characterization of a thermo-tolerant uracil DNA glycosylase (UdgB) from Mycobacterium tuberculosis. DNA Repair (Amst.) 6:1517-28 |
|---|---|
| Abstract |
Uracil DNA glycosylases (UDGs) excise uracil from DNA and initiate the base (uracil) excision repair pathway. Ung, a highly conserved protein, is the only UDG characterized so far in mycobacteria. Here, we show that Rv1259 from Mycobacterium tuberculosis codes for a double-stranded DNA (dsDNA) specific UDG (MtuUdgB). MtuUdgB is thermo-tolerant, contains Fe-S cluster and, in addition to uracil, it excises ethenocytosine and hypoxanthine from dsDNA. MtuUdgB is product inhibited by AP-site containing dsDNA but not by uracil. While MtuUdgB excises uracil present as a single-nucleotide bulge in dsDNA, it is insensitive to inhibition by dsDNA containing AP-site in the bulge. Interestingly, in the presence of cellular factors, the uracil excision activity of MtuUdgB is enhanced, and when introduced into E. coli (ung(-)), it rescues its mutator phenotype and prevents C to T mutations in DNA. Novel features of the mechanism of action of MtuUdgB and the physiological significance of the family 5 UDG in mycobacteria have been discussed. |
| Links |
PubMed Online version:10.1016/j.dnarep.2007.05.001 |
| Keywords |
Amino Acid Sequence; Base Sequence; Cloning, Molecular; DNA Primers; Electrophoretic Mobility Shift Assay; Enzyme Stability; Hot Temperature; Molecular Sequence Data; Mutation; Mycobacterium tuberculosis/enzymology; Sequence Homology, Amino Acid; Substrate Specificity; Uracil-DNA Glycosidase/chemistry; Uracil-DNA Glycosidase/genetics; Uracil-DNA Glycosidase/isolation & purification; Uracil-DNA Glycosidase/metabolism |
| edit table |
Significance
You can help EcoliWiki by summarizing why this paper is useful
Useful Materials and Methods
You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.
Annotations
<annotationlinks/>
EcoliWiki Links
Add links to pages that link here (e.g. gene, product, method pages)
References
See Help:References for how to manage references in EcoliWiki.