Background
- The gastrointestinal tract is normally colonized with a number of microbes
- Comprised of an estimated 35,000 bacterial species
- The gut flora are impacted by:
- Mode of delivery at birth (Cesarean section versus vaginal delivery)
- Diet during infancy (breast milk versus formula)
- Diet during adulthood (plant-based or meat-based)
- Use of antimicrobials
- May play a role in a number of diseases
Members
- Bacteria are generally either in the phyla Bacteroidetes or Firmicutes
- Varies by location
- Esophagus: Bacteroides, Gemella, Megasphaera, Pseudomonas, Prevotella, Rothia, Streptococcus, Veillonella
- Stomach: Streptococcus, Lactobacillus, Prevotella, Enterococcus, Helicobacter pylori
- Small intestine: Bacteroides, Clostridium, Streptococcus, Lactobacillus, Proteobacteria, Enterococcus
- Cecum: Lachnospira, Roseburia, Butyrivibrio, Ruminococcus, Fecalibacterium, Fusobacterium
- Colon: Bacteroides, Clostridium, Prevotella, Porphyromonas, Eubacterium, Ruminococcus, Streptococcus, Enterobacterium, Enterococcus, Lactobacillus, Peptostreptococcus, Fusobacterium
Further Reading