title: Subspeciation of Bifidobacterium longum by multilocus approaches and amplified fragment length polymorphism: Description of B. longum subsp. suillum subsp. nov., isolated from the faeces of piglets.
abstract: The species Bifidobacterium longum is currently divided into three subspecies, B. longum subsp. longum, B. longum subsp. infantis and B. longum subsp. suis. This classification was based on an assessment of accumulated information on the species' phenotypic and genotypic features. The three subspecies of B. longum were investigated using genotypic identification [amplified-fragment length polymorphism (AFLP), multilocus sequence analysis (MLSA) and multilocus sequence typing (MLST)]. By using the AFLP and the MLSA methods, we allocated 25 strains of B. longum into three major clusters corresponding to the three subspecies; the cluster comprising the strains of B. longum subsp. suis was further divided into two subclusters differentiable by the ability to produce urease. By using the MLST method, the 25 strains of B. longum were divided into eight groups: four major groups corresponding to the results obtained by AFLP and MLSA, plus four minor disparate groups. The results of AFLP, MLSA and MLST analyses were consistent and revealed a novel subspeciation of B. longum, which comprised three known subspecies and a novel subspecies of urease-negative B. longum, for which the name B. longum subsp. suillum subsp. nov. is proposed, with type strain Su 851(T)=DSM 28597(T)=JCM 19995(T).
authors.affiliation: Yakult Central Institute, 5-11 Izumi, Kunitachi, Tokyo 186-8650, Japan.
authors.forename: Emiko
authors.initials: E
authors.lastname: Yanokura
authors.affiliation: Yakult Honsha European Research Center for Microbiology ESV, Technologiepark 4, 9052 Zwijnaarde, Belgium.
authors.forename: Kaihei
authors.initials: K
authors.lastname: Oki
authors.affiliation: Yakult Central Institute, 5-11 Izumi, Kunitachi, Tokyo 186-8650, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Makino
authors.affiliation: Department of Agricultural Sciences, University of Bologna, Viale Fanin 42, 40127 Bologna, Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Modesto
authors.affiliation: Lactic acid Bacteria and Mucosal Immunity Team, Institut Pasteur de Lille, Rue Prof. Calmette, F-59019 Lille Cedex, France; Center for Infection and Immunity of Lille, F-59019 Lille, France; Université Lille Nord de France, F-59019 Lille, France; CNRS, UMR 8204, F-59019 Lille, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Pot
authors.affiliation: Department of Agricultural Sciences, University of Bologna, Viale Fanin 42, 40127 Bologna, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Mattarelli
authors.affiliation: Department of Agricultural Sciences, University of Bologna, Viale Fanin 42, 40127 Bologna, Italy.
authors.forename: Bruno
authors.initials: B
authors.lastname: Biavati
authors.affiliation: Department of Animal Science and Technology, National Taiwan University, No. 50, Lane 155, Sec 3, Keelung Rd., Taipei 10673, Taiwan, ROC. Electronic address: koichi_wtnb@yahoo.co.jp.
authors.forename: Koichi
authors.initials: K
authors.lastname: Watanabe
mesh_terms: D054458:Amplified Fragment Length Polymorphism Analysis; D000818:Animals; D000831:Animals, Newborn; D001644:Bifidobacterium / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D016000:Cluster Analysis; D005243:Feces / Q000382:microbiology*; D005838:Genotype; D008969:Molecular Sequence Data; D058885:Multilocus Sequence Typing; D017422:Sequence Analysis, DNA; D013552:Swine
keywords: AFLP; Bifidobacterium longum; MLSA; MLST; Subspeciation; Urease activity