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Quantitative Polymerase Chain Reaction-based Analyses of Murine Intestinal Microbiota After Oral Antibiotic Treatment
Published on: November 17, 2018
[A preliminary analysis of changes in composition of intestinal microbiota during infancy using polymerase chain
Shan-Shan Li1, Jun-Jie Miao, Zi-Xi Wu
1Department of Nutrition, Food Safety and Toxicology, West China School of Public Health, Sichuan University, Chengdu 610041, China. nrb47389@nifty.com.
Insights
Infant gut bacteria composition changes significantly after birth. Obligate aerobes like Proteobacteria colonize first, followed by anaerobes and finally dominant Bifidobacterium (Actinobacteria).
Area of Science:
- Microbiology
- Infant Health
- Gut Microbiome Research
Background:
- The infant gut microbiome plays a crucial role in immune system development and overall health.
- Understanding the dynamics of bacterial colonization is key to identifying potential health implications.
Purpose of the Study:
- To investigate the composition of bacteria in infant stools.
- To analyze the colonization patterns of the intestinal microbiota during early life.
Main Methods:
- Collected fresh stool samples from 15 healthy infants at multiple time points from birth up to 12 months.
- Utilized Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis (PCR-DGGE) for microbiota analysis and sequencing of dominant bacteria.
Main Results:
- Significant temporal changes in intestinal microbiota composition were observed post-birth.
- Proteobacteria (obligate aerobes) were the earliest colonizers, followed by Firmicutes and Verrucomicrobia.
- Actinobacteria, primarily Bifidobacterium, colonized later and became dominant.
Conclusions:
- The infant gut is colonized sequentially by different bacterial groups.
- Obligate aerobes establish early, succeeded by obligate and facultative anaerobes, with Actinobacteria dominating later in infancy.
Objective:
To investigate the composition of bacteria in the stools of infants and the colonization of intestinal microbiota during infancy.
Methods:
Fresh stools were collected from 15 healthy infants at 0, 2, 4, 7, 10, 14, and 28 days and 3, 6, and 12 months after birth. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) was used to analyze the composition of intestinal microbiota, perform sequencing of dominant bacteria, and to analyze the changes in the composition of intestinal microbiota during infancy.
Results:
DGGE fingerprint showed that the composition of intestinal microbiota during infancy changed significantly over time after birth. The cloning and sequencing results indicated that Proteobacteria colonized the earliest, mainly the obligate aerobes Enterobacter and Pseudomonas, followed by the obligate anaerobes (Clostridium hathewayi and Veillonella parvula) and the facultative anaerobe Clostridium ramosum in Firmicutes, and Verrucomicrobia. Actinobacteria colonized the latest, mainly Bifidobacterium, and gradually became dominant bacteria.
Conclusions:
During infancy, obligate aerobes colonize the intestinal tract the earliest, followed by obligate anaerobes and facultative anaerobes. Proteobacteria colonizes the earliest, followed by Firmicutes and Verrucomicrobia, and Actinobacteria, mainly Bifidobacterium, colonizes the latest.
