title: Molecular characterization of Cronobacter lipopolysaccharide O-antigen gene clusters and development of serotype-specific PCR assays.
abstract: Cronobacter (formerly Enterobacter sakazakii) is a recently defined genus consisting of six species, C. sakazakii, C. malonaticus, C. dublinensis, C. muytjensii, C. turicensis, and Cronobacter genomospecies 1. In this study, MboII restriction fragment length polymorphism (RFLP) patterns of O-antigen gene clusters, located between galF and gnd, were used to identify serotypes in Cronobacter spp. Seven O-antigen RFLP clusters were generated, including three C. sakazakii clusters, previously identified as serotypes O1, O2, and O3. The O-antigen regions of six strains with unique RFLP patterns, including two C. sakazakii strains, two C. malonaticus strains, one C. turicensis strain, and one C. muytjensii strain, revealed three O-antigen gene clusters shared among Cronobacter species. PCR assays were developed, targeting the wzx O-antigen polymerase gene, and used to screen 231 Cronobacter strains to determine the frequency of these newly identified serotypes.
authors.affiliation: Lab 3412, MOD 1 Facility, Virulence Mechanisms Branch (HFS-025), Division of Virulence Assessment, OARSA, Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration, 8301 Muirkirk Road, Laurel, MD 20708, USA. karen.jarvis@fda.hhs.gov
authors.forename: K G
authors.initials: KG
authors.lastname: Jarvis
authors.forename: C J
authors.initials: CJ
authors.lastname: Grim
authors.forename: A A
authors.initials: AA
authors.lastname: Franco
authors.forename: G
authors.initials: G
authors.lastname: Gopinath
authors.forename: V
authors.initials: V
authors.lastname: Sathyamoorthy
authors.forename: L
authors.initials: L
authors.lastname: Hu
authors.forename: J A
authors.initials: JA
authors.lastname: Sadowski
authors.forename: C S
authors.initials: CS
authors.lastname: Lee
authors.forename: B D
authors.initials: BD
authors.lastname: Tall
mesh_terms: D001431:Bacteriological Techniques / Q000379:methods*; D016000:Cluster Analysis; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004755:Enterobacteriaceae / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D004756:Enterobacteriaceae Infections / Q000382:microbiology; D004783:Environmental Microbiology; D005516:Food Microbiology; D008969:Molecular Sequence Data; D005810:Multigene Family; D019081:O Antigens / Q000235:genetics*; D016133:Polymerase Chain Reaction / Q000379:methods*; D012150:Polymorphism, Restriction Fragment Length; D017422:Sequence Analysis, DNA
chemical_list: D017931:DNA Primers; D004269:DNA, Bacterial; D019081:O Antigens