We compare two techniques which enable selective, nucleotide-specific covalent modification of human genomic DNA, as assayed by quantitative ligation- mediated PCR. In the first, a purine motif triplex-forming oligonucleotide with a terminally appended chlorambucil was shown to label a target guanine residue adjacent to its binding site in 80% efficiency at 0.5 microM. Efficiency was higher in ...

Infections caused by Naegleria fowleri, Acanthamoeba spp., and Balamuthia mandrillaris occur throughout the world and pose many diagnostic challenges. To date, at least 440 cases of severe central nervous system infections caused by these amebas have been documented worldwide. Rapid and specific identification of these free-living amebas in clinical samples is of crucial importance for efficien...

The triplex PCR of Clermont et al. [Clermont, O., Bonacorsi, S., Bingen, E., 2000. Rapid and simple determination of the Escherichia coli phylogenetic groups. Appl. Environ. Microbiol. 66, 4555-4558.] was used to genotype E. coli isolates from the Mid-Atlantic region of the USA, obtained from freshwater, animal internal organs, and feces. Of 445 isolates subjected to genotyping, 118 isolates (2...

The genus Campylobacter is globally recognised as the leading bacterial cause of human foodborne gastroenteritis. Every year around 8000 Swedes are infected by Campylobacter. Most people are infected by thermotolerant Campylobacter species, commonly C. jejuni and C. coli. In this study a triplex real-time PCR has been developed in order to be a last step in a qualitative method for identificati...

Bacterial cultures of cloaca swabs from 86 captivity kept psittacidaes revealed 17 Escherichia coli bearing birds sharing strains which, on the basis of enterobacterial repetitive intergenic consensus (ERIC) PCR analysis, proved to be genetically similar. Further, triplex PCR specific for the genetic markers chuA, yjaA, and TSPE4.C2 was used to assign the strains to the E. coli reference collec...

The formation of triplex DNA using unmodified, purine-rich oligonucleotides (ODNs) is inhibited by physiologic levels of potassium. Changing negative phosphodiester bonds in a triplex forming oligonucleotide (TFO) to neutral linkages causes a small increase in triplex formation. When phosphodiester bonds in a TFO are converted to positively-charged linkages the formation of triplex DNA increase...