Detection of Enterobacter sakazakii strains by real-time PCR.
A precise 5' nuclease (TaqMan) real-time PCR was developed and validated in house for the specific detection of Enterobacter sakazakii isolates. Specifically designed nonpatented primers and a hydrolysis (TaqMan) probe were used to target the 16S rRNA gene. All 27 E. sakazakii and 141 non-E. sakazakii strains tested with the real-time PCR were identified correctly. To monitor false-negative results, an internal amplification control was coamplified with the same primers used for the E. sakazakii DNA. The detection probability of the assay was 56% when an E. sakazakii cell suspension containing 10(2) CFU/ml was used as template in the PCR (0.5 CFU per reaction) and 100% with a 10(3) CFU/ml suspension. This PCR assay should be very useful for the diagnostic detection of E. sakazakii in foods, especially powdered infant formula, after cultural enrichment.
Federal Institute for Risk Assessment, Diedersdorfer Weg 1, D-12277 Berlin, Germany. b.malorny@bfr.bund.de
Burkhard
B
Malorny
Martin
M
Wagner
D003257:Consumer Product Safety; D044083:Cronobacter sakazakii / Q000302:isolation & purification*; D005506:Food Contamination / Q000032:analysis*; D005516:Food Microbiology; D005784:Gene Amplification; D006801:Humans; D007223:Infant; D007225:Infant Food / Q000382:microbiology*; D041943:Infant Formula; D016133:Polymerase Chain Reaction / Q000379:methods*; D012329:RNA, Bacterial / Q000032:analysis; D012336:RNA, Ribosomal, 16S / Q000032:analysis
D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S