Skip to main content

Genetic and phenotypic diversity of Bifidobacterium thermacidophilum fecal isolates from newborns

Buy Article:

$50.00 plus tax (Refund Policy)


This study was undertaken to genetically identify and phenotypically characterize 14 bifidobacteria isolated from 20 breast-fed newborns. These isolates showed 98%–99% similarity to Bifidobacterium thermacidophilum subsp. suis based on 16S rDNA. Further analysis by pulsed-field gel electrophoresis of chromosomal DNA digested with XbaI revealed 4 distinct restriction patterns. The predominant pattern, shared by 8 (57%) isolates, produced a macro-restriction profile with about 13 large fragments ranging in size from>242.5 to 23.1kb, whereas the other 6 displayed 3 distinct restriction profiles all characterized by more micro- than macro-restriction, with fragments ranging in size from 97 to 9.4kb. Phenotypic characteristics, including carbohydrate fermentation profile, maximal growth temperature, and antibiotic susceptibility, varied widely even among strains showing the same restriction profile. The presence of B.thermacidophilum in stools of newborn infants may indicate the potential of these bacteria for aiding the development of the intestinal ecosystem.

Cette étude a été entreprise afin d’identifier génétiquement et de caractériser phénotypiquement quatorze bifido-bactéries isolées de vingt nouveau-nés nourris au sein. Ces isolats ont démontré 98%– 99% de similarité avec Bifidobacterium thermacidophilum subsp. suis sur la base de la séquence de l’ADNr 16S. Des analyses plus poussées par électrophorèse sur gel en champ pulsé de l’ADN chromosomique digéré avec XbaI ont révélé 4 patrons de restriction distincts. Le patron prédominant, partagé par 8 (57%) isolats, produisait un profil de macro-restriction d’environ 13 longs fragments de >242,5 à 23,1 kb, alors que les 6 autres isolats présentaient 3 profils de restriction distincts, davantage caractérisés à l’échelle de la micro-restriction, dont les fragments s’échelonnaient de 97 à 9,4 kb. Les caractéristiques phénotypiques, dont le profil de fermentation d’hydrates de carbone, la température de croissance maximale et la susceptibilité aux antibiotiques, variaient beaucoup, même parmi les souches présentant le même profil de restriction. La présence de B. thermacidophilum dans les selles des nouveau-nés peut refléter le potentiel d’aide de ces bactéries dans le développement de l’écosystème intestinal.

Document Type: Research Article

Publication date: December 1, 2007

More about this publication?
  • Published since 1954, this monthly journal contains new research in the field of microbiology including applied microbiology and biotechnology; microbial structure and function; fungi and other eucaryotic protists; infection and immunity; microbial ecology; physiology, metabolism and enzymology; and virology, genetics, and molecular biology. It also publishes review articles and notes on an occasional basis, contributed by recognized scientists worldwide.
  • Information for Authors
  • Submit a Paper
  • Subscribe to this Title
  • Terms & Conditions
  • Sample Issue
  • Reprints & Permissions
  • Ingenta Connect is not responsible for the content or availability of external websites

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more