Detection of Enterobacter sakazakii and other pathogens associated with infant formula powder by use of a DNA microarray.
Pathogen detection is critical to the process of generating and testing powdered infant formula (PIF). An obstacle associated with PIF microbial surveillance is that most current procedures are time-consuming and labor-intensive. We have developed a rapid, DNA microarray-based detection technique to identify 10 different pathogenic bacteria associated with PIF contamination based on the 16S-23S rRNA gene internal transcribed spacer (ITS) sequences and wzy (O antigen polymerase) gene. Using this procedure, Enterobacter sakazakii, Salmonella enterica, Klebsiella pneumoniae, Klebsiella oxytoca, Serratia marcescens, Acinetobacter baumannii, Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, and Escherichia coli O157 were identified. One hundred eighty-five strains were used to validate the microarray assay (including 134 target pathogen strains and 51 closely related bacteria). Twenty-seven probes reproducibly detected multiple pathogens with high specificity and sensitivity (0.100 ng genomic DNA or 10(4) CFU/ml). Twenty-one real PIF samples were tested by the microarray with 100% accuracy. The data presented reveal that the designed oligonucleotide microarray is a promising method for basic microbiology, clinical diagnosis, food safety, and epidemiological surveillance.
Wang
Min
M
TEDA School of Biological Sciences and Biotechnology, Nankai University, 23 HongDa St., TEDA, Tianjin 300457, China.
Cao
Boyang
B
Gao
Qili
Q
Sun
Yamin
Y
Liu
Pei
P
Feng
Lu
L
Wang
Lei
L
D001431:Bacteriological Techniques / Q000379:methods*; D044083:Cronobacter sakazakii / Q000235:genetics / Q000302:isolation & purification; D004269:DNA, Bacterial / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000235:genetics; D005516:Food Microbiology; D006090:Gram-Negative Bacteria / Q000235:genetics / Q000302:isolation & purification*; D006094:Gram-Positive Bacteria / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D041943:Infant Formula; D046228:Microarray Analysis / Q000379:methods*; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D015345:Oligonucleotide Probes / Q000235:genetics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA
D004269:DNA, Bacterial; D021903:DNA, Ribosomal Spacer; D015345:Oligonucleotide Probes