vsr

..of a single O(6)mG residue in cells deficient in individual mismatch repair proteins (Dam, MutH, MutS, MutL, or Vsr). We found that MTase repair in cells deficient in Dam or MutH showed wild-type levels of MTase repair...

Overexpression of vsr in Escherichia coli stimulates transition and frameshift mutations. The pattern of mutations suggests that mutagenesis is due to saturation or inactivation of dam-directed mismatch repair.

The Vsr endonuclease of Escherichia coli initiates the repair of T/G mismatches caused by deamination of 5-methylcytosine to thymine...

b>Vsr DNA mismatch endonuclease is the key enzyme of very short patch (VSP) DNA mismatch repair and nicks the T-containing strand at the site of a T-G mismatch in a sequence-dependent manner...

..that the Dcm cytosine methylase of Escherichia coli is maintained at a constant level during cell growth, while Vsr endonuclease levels are growth phase dependent...

The Escherichia coli vsr endonuclease recognises G:T base-pair mismatches in double-stranded DNA and initiates a repair pathway by hydrolysing the phosphate group 5' to the incorrectly paired T...

..This defect is associated with decreased levels of Vsr, the endonuclease which initiates short-patch repair...

b>Vsr mediates very short patch repair in Escherichia coli, correcting T/G mismatches caused by deamination of 5-methylcytosine to thymine. MutS and MutL, part of the post-replication mismatch repair system, stimulate VSP repair...

In Escherichia coli and related bacteria, the very-short-patch (VSP) repair pathway uses an endonuclease, Vsr, to correct T-G mismatches that result from the deamination of 5-methylcytosines in DNA to C-G...

..The structural and biochemical data on the endonuclease that initiates VSP repair, Vsr, suggest that this protein plays a role similar to MutH (also an endonuclease) in MMR...

The crystal structure of the Escherichia coli Vsr endonuclease bound to a C(T/G)AGG substrate revealed that the DNA is held by a pincer composed of a trio of aromatic residues which intercalate into the major groove, and an N-terminus ..

..T:G and U:G mispairs in the methylatable sequence and in related sequences are recognized by the product of vsr, a gene adjacent to dcm. Vsr creates a nick just 5' of the mispaired pyrimidine to initiate the repair...

..It depends on genes vsr and polA and is strongly stimulated by mutL and mutS...

The mechanism of the Escherichia coli DNA T:G mismatch endonuclease (Vsr) has been investigated using oligodeoxynucleotides substituted, at the scissile phosphate, with isomeric phosphorothioates and a 3'-phosphorothiolate...

..5-Methylcytosines in the lacI gene are hotspots for spontaneous C to T mutations. dcm is linked to vsr, a gene required for very short patch (VSP) repair. VSP repair corrects T...

..that the frequency of occurrence of the mutation is influenced by two genes: dcm, the cytosine methylase gene, and vsr, one of the genes involved in very short patch repair...

The crystal structure of very short patch repair (Vsr) endonuclease, in complex with Mg2+ and with duplex DNA containing a TG mismatch, has been determined at 2.3 A resolution. In E...

..Previous studies have shown that the product of gene vsr mediates correction of T:G to C:G in the 5'CTAGG/3'GGTCC context and in some related contexts...

..Further, they provide an explanation for the known scarcity of CTAG containing restriction enzyme sites among the genomes of enteric bacteria and identify VSP repair as a force in shaping the sequence composition of bacterial genomes...

..b>Vsr mismatch repair function of an adjacent gene prevents C-to-T mutagenesis enhanced by this methylation but promotes ..

Very-short-patch repair (Vsr) enzymes occur in a variety of bacteria, where they initiate nucleotide excision repair of G:T mismatches arising by deamination of 5-methyl-cytosines in specific regulatory sequences...

..It is proposed that in E. coli K-12, VSP repair, together with DNA cytosine methylation, constitutes a mutagenesis/recombination system capable of promoting gene-conversion-like unidirectional transfer of short stretches of DNA sequence...

..This gene, named vsr, is not essential for DNA methylation. Remarkably, the 5' end of this gene appears to overlap the 3' end of dcm...

..We also examine the specific repair enzymes involved, namely the endonuclease Vsr in Escherichia coli and two members of the uracil DNA glycosylase (UDG) superfamily in mammals, TDG and MBD4...

A quantitative assay of the sequence-specific endonuclease activity of Vsr DNA mismatch endonuclease is described...

The activities of the Vsr and MutH endonucleases of Escherichia coli are stimulated by MutL. The interaction of MutL with each enzyme is enhanced in vivo by 2-aminopurine treatment and by inactivation of the mutY gene...

..cooperation between these two repair pathways, we analyzed the physical and functional interaction between MutL and Vsr using biophysical and biochemical methods...

..DNA Polymerase I removes and resynthesizes the mismatched T starting from a 5'-nick created by the Vsr endonuclease...

The Escherichia coli vsr endonuclease recognises T:G base-pair mismatches in double-stranded DNA and initiates a repair pathway by hydrolysing the phosphate group 5' to the incorrectly paired T...

..G mismatches can be quantitatively modeled to explain the occurrence of the hot spot at 5meC. This model has implications for mutational hot and cold spots in all organisms...

..Although VSP repair substantially affects the reversion frequency, it may not be as efficient at correcting U:G mismatches as the uracil DNA glycosylase-mediated repair process...

..The gene responsible for the mutator phenotype has been mapped to 43 min on the E. coli chromosome. Several lines of evidence indicate that this gene is distinct from the very short patch repair gene vsr.

The substrate spectrum of Vsr DNA mismatch endonuclease of Escherichia coli K-12 was investigated using fluorescence-labelled oligonucleotide substrates and a DNA sequencer for detection and quantification of substrates and reaction ..

..This ORF codes for a gene, vsr, that is required for a T:G to C:G base mismatch correction process...

b>Vsr endonuclease, which initiates very short patch repair, has been hypothesized to regulate mutation in stationary-phase cells...

b>Vsr endonuclease plays a crucial role in the repair of TG mismatched base pairs, which are generated by the spontaneous degradation of methylated cytidines; Vsr recognizes the mismatched base pair and cleaves the phosphate backbone 5' to ..

The Vsr mismatch endonuclease recognises the sequence CTWGG (W = A or T) in which the underlined thymine is paired with guanine and nicks the DNA backbone on the 5'-side of the mispaired thymine...

..The second is very short patch repair (Vsr) endonuclease, which recognizes a TG mismatch within the five base pair consensus sequence...

..fold, whose structural prototypes are the phage lambda exonuclease, the very short patch repair nuclease (Vsr) and type II restriction enzymes, is shown to encompass by far a greater diversity of nucleases than previously ..

..G mismatches in Dcm target sequences. In the VSP repair pathway, the very short patch repair (Vsr) endonuclease selectively recognizes a T...

..in both pro- and eukaryotes to channel this lesion into base excision repair by removing the T from the mismatch, Vsr endonuclease from Escherichia coli has been described which initiates repair by an endonucleolytic strand incision ..

..hpaIIM is the coding sequence for a 141-aa protein that resembles the very-short-patch-repair endonuclease (Vsr) of Escherichia coli...

..XorII (CGATCG). The 408 nucleotide ORF was 36% identical at the amino acid level to sequences of the E. coli dem-vsr gene, which is required for very short patch repair. X. oryzae pv...

..Further, this system will be used to study the roles played by various DNA repair enzymes, DNA polymerases and accessory proteins in shaping the strand bias and spectrum of mutations responsible for antibody maturation. ..

..This integrated prediction-validation approach should be superior to a purely bioinformatics or a purely biochemical approach and may serve as a paradigm for searching biochemical functions in genomes of all organisms. ..

..This work will create the tools necessary for the monitoring of tumor cells in live animals when they are treated with PB as part of combination chemotherapy. ..

..This Symposium will provide excellent opportunity to those scientists who are unable to attend conferences on either U.S. coast because of the distance or the cost, to participate in a major conference. ..

..coli. The results from this work should create a new perspective on the action of mutagens and provide a greater understanding of the process of transcript elongation. ..