Single-nucleotide polymorphism in the SCCmec-orfX junction distinguishes between livestock-associated MRSA CC398 and human epidemic MRSA strains.

A number of real-time PCR assays for direct detection of methicillinresistant (MRSA) in clinical specimens are targeting staphylococcal cassette chromosome mec (SCCmec) right extremity sequences and the S. aureus chromosomal orfX gene sequences located to the right of the SCCmec integration site. When testing 184 MRSA strains of human and animal origin from geographically distinct locations, we identified several characteristic single-nucleotide polymorphisms (SNPs) within the SCCmec-orfX junction of livestock-associated (LA) MRSA CC398 which serve as suitable strain markers for screening purposes.

Library of prefabricated locked nucleic acid hydrolysis probes facilitates rapid development of reverse-transcription quantitative real-time PCR assays for detection of novel influenza A/H1N1/09 virus.

Background: The emergence of a novel pandemic human strain of influenza A (H1N1/09) has clearly demonstrated the need for flexible tools enabling the rapid development of new diagnostic methods.

Methods: We designed a set of reverse-transcription quantitative real-time PCR (RT-qPCR) assays based on the Universal ProbeLibrary (UPL)--a collection of 165 presynthesized, fluorescence-labeled locked nucleic acid (LNA) hydrolysis probes--specifically to detect the novel influenza A virus. We evaluated candidate primer/UPL-probe pairs with 28 novel influenza A/H1N1/09 patient samples of European and Mexican origin.

Comparison of an internally controlled, large-volume LightCycler assay for detection of Mycobacterium tuberculosis in clinical samples with the COBAS AMPLICOR assay.

We present a sensitive and specific assay for reliable and flexible detection of members of the Mycobacterium tuberculosis complex (MTBC) in clinical samples. This real-time PCR assay, which uses the LightCycler 2.0 instrument and 100-mul glass capillaries, can provide a result within 1 h after DNA extraction.