title: Defining the Genome Features of Escherichia albertii, an Emerging Enteropathogen Closely Related to Escherichia coli.
abstract: Escherichia albertii is a recently recognized close relative of Escherichia coli. This emerging enteropathogen possesses a type III secretion system (T3SS) encoded by the locus of enterocyte effacement, similar to enteropathogenic and enterohemorrhagic E. coli (EPEC and EHEC). Shiga toxin-producing strains have also been identified. The genomic features of E. albertii, particularly differences from other Escherichia species, have not yet been well clarified. Here, we sequenced the genome of 29 E. albertii strains (3 complete and 26 draft sequences) isolated from multiple sources and performed intraspecies and intragenus genomic comparisons. The sizes of the E. albertii genomes range from 4.5 to 5.1 Mb, smaller than those of E. coli strains. Intraspecies genomic comparisons identified five phylogroups of E. albertii. Intragenus genomic comparison revealed that the possible core genome of E. albertii comprises 3,250 genes, whereas that of the genus Escherichia comprises 1,345 genes. Our analysis further revealed several unique or notable genetic features of E. albertii, including those responsible for known biochemical features and virulence factors and a possibly active second T3SS known as ETT2 (E. coli T3SS 2) that is inactivated in E. coli. Although this organism has been observed to be nonmotile in vitro, genes for flagellar biosynthesis are fully conserved; chemotaxis-related genes have been selectively deleted. Based on these results, we have developed a nested polymerase chain reaction system to directly detect E. albertii. Our data define the genomic features of E. albertii and provide a valuable basis for future studies of this important emerging enteropathogen.
authors.affiliation: Department of Microbiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Japan.
authors.forename: Tadasuke
authors.initials: T
authors.lastname: Ooka
authors.affiliation: Department of Bacteriology, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Yoshitoshi
authors.initials: Y
authors.lastname: Ogura
authors.affiliation: Division of Microbiology, Department of Infectious Diseases, Faculty of Medicine, University of Miyazaki, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Katsura
authors.affiliation: Division of Bacteriology, Osaka Prefectural Institute of Public Health, Osaka, Japan.
authors.forename: Kazuko
authors.initials: K
authors.lastname: Seto
authors.affiliation: Center for Animal Disease Control and Prevention, National Institute of Animal Health, Ibaraki, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Kobayashi
authors.affiliation: Department of Microbiology, Miyazaki Prefectural Institute for Public Health and Environment, Miyazaki, Japan.
authors.forename: Kimiko
authors.initials: K
authors.lastname: Kawano
authors.affiliation: Division of Microbiology, Kumamoto Prefectural Institute of Public Health and Environmental Science, Kumamoto, Japan.
authors.forename: Eisuke
authors.initials: E
authors.lastname: Tokuoka
authors.affiliation: Division of Microbiology, Kumamoto Prefectural Institute of Public Health and Environmental Science, Kumamoto, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Furukawa
authors.affiliation: Division of Microbiology, Kumamoto Prefectural Institute of Public Health and Environmental Science, Kumamoto, Japan.
authors.forename: Seiya
authors.initials: S
authors.lastname: Harada
authors.affiliation: Department of Microbiology, Miyazaki Prefectural Institute for Public Health and Environment, Miyazaki, Japan.
authors.forename: Shuji
authors.initials: S
authors.lastname: Yoshino
authors.affiliation: Department of Microbiology, Yamagata Prefectural Institute of Public Health, Yamagata, Japan.
authors.forename: Junji
authors.initials: J
authors.lastname: Seto
authors.affiliation: Department of Infection Diseases Bacteriology, Hokkaido Institute of Public Health, Hokkaido, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Ikeda
authors.affiliation: Department of Infection Diseases Bacteriology, Hokkaido Institute of Public Health, Hokkaido, Japan.
authors.forename: Keiji
authors.initials: K
authors.lastname: Yamaguchi
authors.affiliation: Division of Microbiology, Department of Infectious Diseases, Faculty of Medicine, University of Miyazaki, Japan.
authors.forename: Kazunori
authors.initials: K
authors.lastname: Murase
authors.affiliation: Division of Microbiology, Department of Infectious Diseases, Faculty of Medicine, University of Miyazaki, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Gotoh
authors.affiliation: Department of Microbiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Imuta
authors.affiliation: Department of Microbiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Japan.
authors.forename: Junichiro
authors.initials: J
authors.lastname: Nishi
authors.affiliation: Department of Microbiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Japan.
authors.forename: Tânia A
authors.initials: TA
authors.lastname: Gomes
authors.affiliation: Department of Microbiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Japan.
authors.forename: Lothar
authors.initials: L
authors.lastname: Beutin
authors.affiliation: Department of Bacteriology, Faculty of Medical Sciences, Kyushu University, Fukuoka, Japan thayash@bact.med.kyushu-u.ac.jp.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Hayashi
mesh_terms: D001483:Base Sequence; D054308:Enteropathogenic Escherichia coli / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D022761:Gene Transfer, Horizontal; D016680:Genome, Bacterial; D008969:Molecular Sequence Data; D014774:Virulence / Q000235:genetics
keywords: Escherichia albertii; core genome; detection system; emerging enteropathogen; genomic comparison; interspecies horizontal gene transfer