The SCCmec carries the mecA gene, which encodes penicillin binding protein PBP2a, the main causal factor of methicillin resistance. Different types of SCCmec cassettes and their variants have been identified [10, 11]. The current methods for MRSA detection are based on either the phenotypic expression such as oxacillin resistance, or genotypic characterization. For this study, we used modified broad-range PCR primers that originate from the conserved regions of genes that encode the topoisomerases together with specific oligonucleotide probes located at hyper-variable regions flanked by the primers. Using these primers and probes, single or even multiple infection-causing bacteria could be simultaneously

learn more detected and identified. The bacterial pathogen panel of the assay covered the following species: selleck chemicals Acinetobacter baumannii, Enterococcus faecalis, Enterococcus faecium, Haemophilus influenzae, Klebsiella pneumoniae, check details Listeria monocytogenes, Neisseria meningitidis, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus agalactiae, Streptococcus pneumoniae, Streptococcus pyogenes and selected CNS species. These bacteria are examples of highly virulent, potentially multi-antimicrobial resistant or the most common etiologic agents associated with various life-threatening conditions. Such

conditions include: sepsis, infective endocarditis and central nervous system infection. All these conditions necessitate rapid and accurate diagnostics to improve the chances of a positive outcome for

the patient. We used the ArrayTube™ as a microarray platform for the probes. The ArrayTube™ has been demonstrated to detect and Immune system identify bacterial pathogens with a high degree of sensitivity [12–14], differentiate between various pathotypes of the same bacterial species [15] and to be capable of detecting antimicrobial resistance genes [16] from an isolated DNA sample. Furthermore, by including specific primers and probes for the mecA methicillin resistance gene in the same assay, we were able to associate the mecA gene with a particular Staphylococcus species present in the sample. The combination of broad-range PCR and array-based methods provided a sensitive and specific approach for detecting and identifying bacterial pathogens along with finding possible resistance markers. Results Assay design First, we re-designed and modified the bacterial broad-range gyrB/parE primers [4] by using inosines to reduce the level of degeneration. These modifications also facilitated the use of a novel PCR method for the assay (PCR program described in Materials and Methods). The PCR method had two distinct phases: a three-step PCR phase that exponentially produced dsDNA, followed by a two-step PCR phase that took place under two different conditions and which produced ssDNA in a linear manner. The method is based on partly overlapping annealing temperatures of the forward and reverse primers.