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Updated: Jul 20, 2026
08:05
Guided Protocol for Fecal Microbial Characterization by 16S rRNA-Amplicon Sequencing
Published on: March 19, 2018
Diversity of the human intestinal microbial flora.
Paul B Eckburg1, Elisabeth M Bik, Charles N Bernstein
1Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Room S-169, 300 Pasteur Drive, Stanford CA 94305-5107, USA. eckburg1@stanford.edu
Science (New York, N.Y.)
|April 16, 2005
Summary
The human gut microbiome, essential for health, remains poorly understood. This study reveals significant diversity and variability in gut microbial communities, highlighting novel species and differences between gut sites.
Area of Science:
- Microbiology
- Human Microbiome Research
- Genomics
Background:
- The human gut microflora functions as a vital 'organ' influencing nutrition, epithelial development, and innate immunity.
- Despite its importance, fundamental characteristics of the gut microbiome are not well-defined.
Purpose of the Study:
- To enhance understanding of gut microbial diversity by analyzing a large dataset of prokaryotic ribosomal RNA gene sequences.
- To characterize the composition and variability of the human intestinal microflora in healthy subjects.
Main Methods:
- Analysis of 13,355 prokaryotic ribosomal RNA gene sequences.
- Sampling from multiple colonic mucosal sites and fecal matter of healthy individuals.
- Bioinformatic analysis to identify microbial species and community structures.
Main Results:
- A substantial proportion of identified bacterial sequences belonged to uncultivated species and novel microorganisms.
- Significant variability was observed in microbial community composition among different subjects.
- Distinct differences were found in community composition between fecal samples and colonic mucosal samples.
Conclusions:
- The human gut harbors a highly diverse and variable microbial ecosystem.
- Further characterization of this complex ecosystem is crucial for understanding its role in human health and disease.
- Discovery of novel microbial species underscores the need for continued exploration of the gut microbiome.
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