Gut Pathogens (Feb 2013)

Metagenomic profile of gut microbiota in children during cholera and recovery

  • Monira Shirajum,
  • Nakamura Shota,
  • Gotoh Kazuyoshi,
  • Izutsu Kaori,
  • Watanabe Haruo,
  • Alam Nur Haque,
  • Nakaya Takaaki,
  • Horii Toshihiro,
  • Ali Sk Imran,
  • Iida Tetsuya,
  • Alam Munirul

DOI
https://doi.org/10.1186/1757-4749-5-1
Journal volume & issue
Vol. 5, no. 1
p. 1

Abstract

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Abstract Background The diverse bacterial communities colonizing the gut (gastrointestinal tract) of infants as commensal flora, which play an important role in nutrient absorption and determining the state of health, are known to alter due to diarrhea. Method Bacterial community dynamics in children suffering from cholera and during recovery period were examined in the present study by employing metagenomic tool, followed by DNA sequencing and analysis. For this, bacterial community DNA was extracted from fecal samples of nine clinically confirmed cholera children (age 2–3 years) at day 0 (acute cholera), day 2 (antibiotic therapy), day 7 and, and day 28, and the variable region of 16S rRNA genes were amplified by universal primer PCR. Results 454 parallel sequencing of the amplified DNA followed by similarity search of the sequenced data against an rRNA database allowed us to identify V. cholerae, the cause of cholera, in all nine children at day 0, and as predominant species in six children, accounting for 35% of the total gut microbiota on an average in all the nine children. The relative abundance (mean ± sem %) of bacteria belonging to phyla Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria, was 55 ± 7, 18 ± 4, 13 ± 4, and 8 ± 4, respectively, at day 0, while these values were 12 ± 4, 43 ± 4, 33 ± 3, and 12 ± 2, respectively, at day 28. As antibiotic therapy began, V. cholerae count declined significantly (pEscherichia coli, Enterococcus, and Veillonella increased at day 2 (antibiotic therapy) while Bifidobacterium, Bacteroides, and Ruminococcus decreased. Conclusion Cholera results expulsion of major commensal bacteria of phyla Bacteroidetes, Firmicutes, and Actinobacteria, and increase of harmful Proteobacteria to colonize the gut during acute and convalescence states. The observed microbiota disruption might explain the prevalent malnutrition in children of Bangladesh where diarrheal diseases are endemic.

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