Sample storage conditions induce post-collection biases in microbiome profiles.

Area of Science:

• Microbiology
• Genomics
• Bioinformatics

Background:

• Fecal microbial community analysis is crucial for understanding host health.
• Standardization of sample collection and storage is essential for reliable results.
• Investigating the impact of various storage conditions on fecal DNA quality is necessary.

Purpose of the Study:

• To evaluate the influence of different stabilization and storage strategies on fecal microbial DNA quality and composition.
• To identify optimal storage conditions that minimize post-collection bias.
• To provide guidance for researchers handling fecal samples for microbial analysis.

Main Methods:

• Murine DNA samples were subjected to various storage conditions for one month.
• Conditions included ambient temperature, different temperatures (-80°C, -20°C, 4°C), and hypoxic conditions.
• Samples were stored with or without preservative buffers (EDTA, lysis buffer).

Main Results:

• Storage in lysis buffer reduced DNA content but maintained integrity.
• EDTA storage significantly impacted alpha diversity and community structure.
• Distinct changes in bacterial phyla and species abundance were observed across strategies.
• Metabolic function analysis revealed condition-specific alterations, notably in tyrosine metabolism.

Conclusions:

• Each long-term storage strategy introduces unique post-collection biases.
• Researchers must consider these biases when interpreting fecal microbial community data.
• Careful selection of storage methods is critical for accurate microbiome research.