title: Transmission of intestinal Bifidobacterium longum subsp. longum strains from mother to infant, determined by multilocus sequencing typing and amplified fragment length polymorphism.
abstract: The gastrointestinal tracts of neonates are colonized by bacteria immediately after birth. It has been discussed that the intestinal microbiota of neonates includes strains transferred from the mothers. Although some studies have indicated possible bacterial transfer from the mother to the newborn, this is the first report confirming the transfer of bifidobacteria at the strain level. Here, we investigated the mother-to-infant transmission of Bifidobacterium longum subsp. longum by genotyping bacterial isolates from the feces of mothers before delivery and of their infants after delivery. Two hundred seven isolates from 8 pairs of mothers and infants were discriminated by multilocus sequencing typing (MLST) and amplified fragment length polymorphism (AFLP) analysis. By both methods, 11 strains of B. longum subsp. longum were found to be monophyletic for the feces of the mother and her infant. This finding confirms that these strains were transferred from the intestine of the mother to that of the infant. These strains were found in the first feces (meconium) of the infant and in the feces at days 3, 7, 30, and 90 after birth, indicating that they stably colonize the infant's intestine immediately after birth. The strains isolated from each family did not belong to clusters derived from any of the other families, suggesting that each mother-infant pair might have unique family-specific strains.
authors.affiliation: Yakult Honsha European Research Center for Microbiology, ESV, Technologiepark 4, 9052 Ghent-Zwijnaarde, Belgium. hiroshi.makino@yher.be
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Makino
authors.forename: Akira
authors.initials: A
authors.lastname: Kushiro
authors.forename: Eiji
authors.initials: E
authors.lastname: Ishikawa
authors.forename: Delphine
authors.initials: D
authors.lastname: Muylaert
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kubota
authors.forename: Takafumi
authors.initials: T
authors.lastname: Sakai
authors.forename: Kenji
authors.initials: K
authors.lastname: Oishi
authors.forename: Rocio
authors.initials: R
authors.lastname: Martin
authors.forename: Kaouther
authors.initials: K
authors.lastname: Ben Amor
authors.forename: Raish
authors.initials: R
authors.lastname: Oozeer
authors.forename: Jan
authors.initials: J
authors.lastname: Knol
authors.forename: Ryuichiro
authors.initials: R
authors.lastname: Tanaka
mesh_terms: D054458:Amplified Fragment Length Polymorphism Analysis / Q000379:methods; D039941:Bifidobacteriales Infections / Q000382:microbiology / Q000635:transmission*; D001644:Bifidobacterium / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D002353:Carrier State / Q000382:microbiology / Q000635:transmission*; D016000:Cluster Analysis; D005243:Feces / Q000382:microbiology; D005838:Genotype; D006801:Humans; D007223:Infant; D058889:Molecular Typing / Q000379:methods*; D058885:Multilocus Sequence Typing / Q000379:methods