Establishing conventional PCR and TaqMan real time PCR assays for detection of Enterobacter aerogenes

Objective To establish a sensitive and specific conventional PCR assay and a TaqMan real time PCR assay for the detection of Enterobacter aerogenes. Methods The primers and probe were designed according to the public sequences of hdc gene coding histidine decarboxylase on NCBI. The specificity was evaluated by using 30 other genus and species strains. The plasmid harboring hdc gene and feces simulated specimens were used to evaluate the sensitivity of the conventional PCR assay and TaqMan real time PCR assay. Results The specificities of conventional PCR assay and TaqMan PCR assay were high in detecting E. aerogenes. The sensitivity of conventional PCR assay for standard plasmid and stimulated feces specimens was 100 copies/l and 1.0105 cfu/g respectively. The sensitivity of TaqMan real time PCR assay for standard plasmid and feces simulated specimens were 33 copies/l and 1.0104 cfu/g respectively. Conventional PCR assay had good repeatability. The inter-andintra-CVs of TaqMan real time PCR assay for standard plasmid were 0.15%-0.98% and 0.55~1.63% respectively. Conclusion Conventional PCR assay and TaqMan real time PCR assay in our study were sensitive and specific for the detection of E. aerogenes.