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Updated: Apr 15, 2026
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Microbiota Analysis Using Two-step PCR and Next-generation 16S rRNA Gene Sequencing
Published on: October 15, 2019
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The human gut microbiome, a taxonomic conundrum
Senthil Alias Sankar1, Jean-Christophe Lagier1, Pierre Pontarotti2
1URMITE, UM63, CNRS7278, IRD198, insermU1095, Institut Hospitalo-Universitaire Méditerranée Infection, Aix-Marseille University, Marseille, France.
Systematic and Applied Microbiology
|April 14, 2015
Summary
The human gut microbiota, comprising over 1000 species, is crucial for health but complex to study. Advances in metagenomics and culture methods reveal its role in diseases, yet challenges remain in fully understanding this ecosystem.
Area of Science:
- Microbiology
- Human Health
- Genomics
Background:
- The human gut microbiota has been studied for 130 years, significantly advancing our knowledge.
- It is the most complex human biota, dominated by Bacteroidetes and Firmicutes, with high inter-individual variability but temporal stability.
- Gut microbiota composition is linked to diseases like IBS, Crohn's disease, colon cancer, type 2 diabetes, and obesity.
Purpose of the Study:
- To review the progress and challenges in understanding the human gastrointestinal microbiota.
- To highlight the influence of gut microbiota on human health.
Main Methods:
- Culture-dependent and culture-independent techniques (metagenomics) are employed.
- High-throughput sequencing and modern culturing methods are used to analyze microbial diversity.
- Methodological limitations and lack of consensus strategies impact data interpretation.
Main Results:
- Over 1000 microbial species have been identified in the human gut.
- Metagenomics reveals associations between gut microbiota and various diseases.
- Culture-independent techniques show the importance of uncultured species, while culturing reveals underestimation of diversity by metagenomics.
Conclusions:
- Understanding the human gastrointestinal microbiota is essential for comprehending its impact on health.
- Current methods have limitations, necessitating further research for a complete understanding.
- Integrating different approaches is key to deciphering the complexity of the gut microbiota.
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