title: Diversity of bifidobacteria within the infant gut microbiota.
abstract: BACKGROUND
  The human gastrointestinal tract (GIT) represents one of the most densely populated microbial ecosystems studied to date. Although this microbial consortium has been recognized to have a crucial impact on human health, its precise composition is still subject to intense investigation. Among the GIT microbiota, bifidobacteria represent an important commensal group, being among the first microbial colonizers of the gut. However, the prevalence and diversity of members of the genus Bifidobacterium in the infant intestinal microbiota has not yet been fully characterized, while some inconsistencies exist in literature regarding the abundance of this genus.
  
  
  RESULTS
  In the current report, we assessed the complexity of the infant intestinal bifidobacterial population by analysis of pyrosequencing data of PCR amplicons derived from two hypervariable regions of the 16 S rRNA gene. Eleven faecal samples were collected from healthy infants of different geographical origins (Italy, Spain or Ireland), feeding type (breast milk or formula) and mode of delivery (vaginal or caesarean delivery), while in four cases, faecal samples of corresponding mothers were also analyzed.
  
  
  CONCLUSIONS
  In contrast to several previously published culture-independent studies, our analysis revealed a predominance of bifidobacteria in the infant gut as well as a profile of co-occurrence of bifidobacterial species in the infant's intestine.
authors.affiliation: Laboratory of Probiogenomics, Department of Genetics, Biology of Microorganisms, Anthropology and Evolution, University of Parma, Parma, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Turroni
authors.forename: Clelia
authors.initials: C
authors.lastname: Peano
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Pass
authors.forename: Elena
authors.initials: E
authors.lastname: Foroni
authors.forename: Marco
authors.initials: M
authors.lastname: Severgnini
authors.forename: Marcus J
authors.initials: MJ
authors.lastname: Claesson
authors.forename: Colm
authors.initials: C
authors.lastname: Kerr
authors.forename: Jonathan
authors.initials: J
authors.lastname: Hourihane
authors.forename: Deirdre
authors.initials: D
authors.lastname: Murray
authors.forename: Fabio
authors.initials: F
authors.lastname: Fuligni
authors.forename: Miguel
authors.initials: M
authors.lastname: Gueimonde
authors.forename: Abelardo
authors.initials: A
authors.lastname: Margolles
authors.forename: Gianluca
authors.initials: G
authors.lastname: De Bellis
authors.forename: Paul W
authors.initials: PW
authors.lastname: O'Toole
authors.forename: Douwe
authors.initials: D
authors.lastname: van Sinderen
authors.forename: Julian R
authors.initials: JR
authors.lastname: Marchesi
authors.forename: Marco
authors.initials: M
authors.lastname: Ventura
mesh_terms: D001483:Base Sequence; D001644:Bifidobacterium / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D017931:DNA Primers / Q000235:genetics; D005243:Feces / Q000382:microbiology; D005260:Female; D041981:Gastrointestinal Tract / Q000382:microbiology*; D005798:Genes, Bacterial; D014644:Genetic Variation; D006801:Humans; D007223:Infant; D054892:Metagenome; D010802:Phylogeny; D011247:Pregnancy; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics
chemical_list: D017931:DNA Primers; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S