title: Comparison of methods for the microbiological identification and typing of Cronobacter species in infant formula.
abstract: Cronobacter species represent an emerging opportunistic foodborne pathogen associated with meningitis and necrotizing enterocolitis in infants. Current evidence indicates that powdered infant formula (PIF) is the main source of Cronobacter contamination. A total of 75 strains of Cronobacter spp. from different geographic regions, as well as from PIF processing environments, were identified and typed with different methods, including biochemical profiling by the API 20E system (bioMérieux, Marcy l'Etoile, France), protein profiling by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), and genotypic profiling by ribotype. Analysis by MALDI-TOF MS and biochemical identification was more accurate compared with ribotype analysis. However, MALDI-TOF MS typing and ribotype analysis showed more discriminatory ability compared with biochemical phenotyping. In conclusion, MALDI-TOF MS is a rapid and reliable tool to identify Cronobacter spp. in PIF and has the potential to trace dissemination of Chronobacter along the production chain.
authors.affiliation: Key Laboratory of Dairy Science, Ministry of Education, Department of Food Science, Northeast Agricultural University, Harbin 150030, China; National Dairy Engineering and Technical Research Center, Harbin 150086, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Chinese Academy of Inspection and Quarantine, Beijing 100123, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Chinese Academy of Inspection and Quarantine, Beijing 100123, China.
authors.forename: X A
authors.initials: XA
authors.lastname: Lu
authors.affiliation: Chinese Academy of Inspection and Quarantine, Beijing 100123, China.
authors.forename: J
authors.initials: J
authors.lastname: Lv
authors.affiliation: National Dairy Engineering and Technical Research Center, Harbin 150086, China.
authors.forename: C X
authors.initials: CX
authors.lastname: Man
authors.affiliation: Key Laboratory of Dairy Science, Ministry of Education, Department of Food Science, Northeast Agricultural University, Harbin 150030, China.
authors.forename: Y L
authors.initials: YL
authors.lastname: Chai
authors.affiliation: Key Laboratory of Dairy Science, Ministry of Education, Department of Food Science, Northeast Agricultural University, Harbin 150030, China; National Dairy Engineering and Technical Research Center, Harbin 150086, China; SynergeticInnovation Center of Food Safety and Nutrition, Harbin 150030, China. Electronic address: yujun_jiang@163.com.
authors.forename: Y J
authors.initials: YJ
authors.lastname: Jiang
mesh_terms: D015373:Bacterial Typing Techniques / Q000379:methods*; D059126:Cronobacter / Q000145:classification* / Q000302:isolation & purification*; D005516:Food Microbiology / Q000379:methods*; D005838:Genotype; D006801:Humans; D007223:Infant; D041943:Infant Formula; D007231:Infant, Newborn; D021521:Ribotyping; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
keywords: Cronobacter species; matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS); powdered infant formula; ribotype