Bacillus subtilis biosensor engineered to assess meat spoilage.

Area of Science:

• Microbiology
• Biotechnology
• Food Science

Background:

• Assessing meat freshness is crucial for food safety and reducing waste.
• Current methods for detecting meat spoilage can be time-consuming or require specialized equipment.
• There is a need for rapid, accessible, and reliable methods to monitor meat quality.

Purpose of the Study:

• To develop a novel cell-based biosensor for assessing meat freshness.
• To identify specific bacterial promoters activated by volatiles from spoiled meat.
• To engineer Bacillus subtilis as a chassis for a meat spoilage biosensor.

Main Methods:

• Transcriptome analysis of Bacillus subtilis exposed to spoiled meat volatiles.
• Identification and cloning of meat spoilage-inducible promoters (e.g., PsboA).
• Construction of a BioBrick compatible plasmid for gene expression in B. subtilis.
• Fusion of the PsboA promoter to a reporter gene (amilGFP) for fluorescence detection.

Main Results:

• Identified specific promoters activated by spoiled meat volatiles, with PsboA showing strong activation.
• Successfully engineered a B. subtilis strain carrying the PsboA-amilGFP construct.
• Demonstrated that the biosensor efficiently produces fluorescent protein in response to spoiled meat volatiles.
• Validated the potential of the engineered promoter for detecting meat spoilage.

Conclusions:

• A novel cell-based biosensor for meat spoilage detection has been successfully developed using Bacillus subtilis.
• The identified PsboA promoter is a reliable indicator of meat spoilage.
• This biosensor offers a promising tool for rapid and accessible meat quality assessment.