RRC ID 53656
Author Sang PB, Srinath T, Patil AG, Woo EJ, Varshney U.
Title A unique uracil-DNA binding protein of the uracil DNA glycosylase superfamily.
Journal Nucleic Acids Res
Abstract Uracil DNA glycosylases (UDGs) are an important group of DNA repair enzymes, which pioneer the base excision repair pathway by recognizing and excising uracil from DNA. Based on two short conserved sequences (motifs A and B), UDGs have been classified into six families. Here we report a novel UDG, UdgX, from Mycobacterium smegmatis and other organisms. UdgX specifically recognizes uracil in DNA, forms a tight complex stable to sodium dodecyl sulphate, 2-mercaptoethanol, urea and heat treatment, and shows no detectable uracil excision. UdgX shares highest homology to family 4 UDGs possessing Fe-S cluster. UdgX possesses a conserved sequence, KRRIH, which forms a flexible loop playing an important role in its activity. Mutations of H in the KRRIH sequence to S, G, A or Q lead to gain of uracil excision activity in MsmUdgX, establishing it as a novel member of the UDG superfamily. Our observations suggest that UdgX marks the uracil-DNA for its repair by a RecA dependent process. Finally, we observed that the tight binding activity of UdgX is useful in detecting uracils in the genomes.
Volume 43(17)
Pages 8452-63
Published 2015-9-30
DOI 10.1093/nar/gkv854
PII gkv854
PMID 26304551
PMC PMC4787834
MeSH Bacterial Proteins / chemistry Bacterial Proteins / genetics Bacterial Proteins / isolation & purification Bacterial Proteins / metabolism* DNA / chemistry DNA / metabolism DNA Repair DNA-Binding Proteins / chemistry DNA-Binding Proteins / genetics DNA-Binding Proteins / isolation & purification DNA-Binding Proteins / metabolism* Mutation Mycobacterium smegmatis / enzymology Rec A Recombinases / metabolism Sequence Homology, Amino Acid Structural Homology, Protein Uracil / metabolism* Uracil-DNA Glycosidase / chemistry Uracil-DNA Glycosidase / classification Uracil-DNA Glycosidase / genetics Uracil-DNA Glycosidase / metabolism* Viral Proteins / metabolism
IF 11.502
Times Cited 15
Prokaryotes E. coli