Measurements are made at 540 nm, and require a non-specific inter

Measurements are made at 540 nm, and require a non-specific intercalating dye [12]. Real-time PCR detection can be performed by using free dyes or labelled sequence-specific probes. One combination of the two techniques uses unlabelled probes for the amplicon detection and Tm determination [13]. Another parallel application was the combination of TaqMan chemistry and the very new, aspecific dye, BTK inhibitor nmr BOXTO, as a multiplex PCR [14]. The novelty of our prototype

system lies in the use of non-specific SYBR Green dye as a donor molecule, instead of a labelled primer or other specific anchor probe. With this technique, it is possible to examine pathogenic fungi, G + and G- bacteria in a single tube multiplex PCR reaction. Results and discussion Discrimination of the fungal, G + and G- bacterial Selleckchem DMXAA pathogens DNA samples from all species studied were prepared and amplified successfully with the SYBR Green dye-based method in the LightCycler instrument. Species-specific Tm-s were obtained by melting-point analysis on three detection channels and all pathogens were identified correctly as fungi or G- or G + bacteria (Table 1). On the F1 channel (540 nm), the melting points of all the amplicons (Tm A) were visible, due to the fluorescent signal of the SYBR Green non-specific intercalating dye. On the F2 (640 nm) and F3 (705 nm) channels, Selleck MRT67307 the G- and the G + probes (Tm P), respectively, gave fluorescence

signals. After the discrimination of the G- and G + strains, the fungal pathogens could be screened, because the fungal strains gave no signal on the F2; F3 channels. Table 1 Melting points of bacterial and fungal amplicons and probes Microbial strains Tm P (°C) Tm A (°C) Gram positive (G+) Mean SD Mean SD Enterococcus faecalis 67.94 0.07 84.14 0.36 Enterococcus faecium 67.84 0.21 84.59 0.78 Listeria monocytogenes 67.80

0.19 86.01 0.36 Staphyloccus aureus 64.85 0.21 83.91 0.54 Staphyloccus epidermidis 64.50 0.30 83.60 0.36 Streptococcus pyogenes 46.54 0.56 84.38 0.78 Gram negative (G-)         Acinetobacter baumannii 66.09 0.15 82.90 0.16 Bacteroides fragilis 48.65 0.18 84.47 0.84 Enterobacter aerogenes 63.95 0.34 83.47 0.48 Enterobacter cloacae 64.98 0.09 84.38 0.24 Escherichia coli 64.69 0.44 84.74 0.54 Carnitine palmitoyltransferase II Haemophilus influenzae 61.99 0.35 84.28 0.30 Klebsiella pneumoniae 65.13 0.23 84.57 0.20 Proteus vulgaris 64.58 0.18 82.87 0.24 Pseudomonas aeruginosa 53.32 0.33 83.00 0.34 Serratia marcescens 64.01 0.30 84.17 0.30 Stenotrophomonas maltophilia 58.10 0.07 84.42 0.15 Fungi         Candida albicans – - 87.1 0.33 Candida dubliniensis – - 85.5 0.50 Candida quillermondii – - 85.1 0.70 Candida krusei – - 89.8 0.02 Candida parapsilosis – - 85.4 0.88 Candida tropicalis – - 84.5 0.75 Aspergillus fumigatus – - 91.0 0.38 All the amplicons Tm were measured at the F1 channel (540 nm). The signal was generated by aspecific SybrGreen dye.

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