A method for the enrichment of heteroduplex DNAs from hybrid DNA mixtures by endonuclease VII is reported. The procedure is based on the ability of a GST-fused cleavage-deficient mutant endonuclease VII (EVII-N62D(GST)) to bind to mismatching nucleotides in heteroduplex DNAs identical to the wild-type enzyme. The GST tag was used for stable immobilisation of the protein to Glutathione Sepharose...

The ability of related DNAs to undergo recombination decreases with increased sequence divergence. Mismatch repair has been proposed to be a key factor in preventing homeologous recombination; however, the contribution of mismatch repair is not universal. Although mismatch repair has been proposed to act by preventing strand exchange and/or inactivating multiply mismatched heteroduplexes, there...

Heteroduplex mobility analysis (HMA) was used to genotype hepatitis C viruses (HCV) with PCR fragments derived from the 5' untranslated region (5'-UTR) or the NS5b region. HCV 5'-UTR fragments were amplified from 296 serum samples by use of a combined reverse transcription-PCR assay, and the genotypes of isolates were determined by sequencing. HCV genotype distributions in Australia were 39% fo...

To gain insight regarding the mechanisms that extend heteroduplex joints in Escherichia coli recombination, we investigated the effect of recG and ruv genotypes on heteroduplex strand polarity in intramolecular recombination products. We also examined the cumulative effect of mutational inactivation of RecG and single-strand-specific exonucleases on recombination proficiency and the role of Chi...

REPAIR of meiotically induced double-strand breaks duplex-rejection model. The danger of ignoring symmetric heteroduplexes was made especially relevant by (DSBs; Figure 1) is associated with a gradient of gene conversion, in which conversion frequency is high Hillers and Stahl’s (1999) evidence that symmetric heteroduplex does form in yeast (see the appendix, near the DSB site and falls with di...

The utility of restriction endonucleases as a tool in molecular biology is in large part due to the high degree of specificity with which they cleave well-characterized DNA recognition sequences. The specificity of restriction endonucleases is not absolute, yet many commonly used assays of biological phenomena and contemporary molecular biology techniques rely on the premise that restriction en...

The formation of heteroduplex joints in Escherichia coli recombination is initiated by invasion of double-stranded DNA by a single-stranded homologue. To determine the polarity of the invasive strand, linear molecules with direct terminal repeats were released by in vivo restriction of infecting chimeric phage DNA and heteroduplex products of intramolecular recombination were analyzed. With thi...

BACKGROUND Identification of gene rearrangements and clonality analysis are important techniques for the diagnosis of malignant lymphoproliferative diseases. These methods have various sensitivities based on the type of primer used and method of determination of polymerase chain reaction (PCR) products. This study aimed at determining the clonality of B cell non-Hodgkin lymphoma in Iranian pati...

Here we describe DNA sample preparation methods that allow the rapid, simultaneous generation of both single-stranded conformational polymorphism (SSCP) and heteroduplex DNA elements from a single sample in a single tube, which are suitable for direct injection into a capillary electrophoresis (CE) instrument with excellent sensitivity of genetic mutation detection. The p53 gene was used as a m...