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Updated: Jun 30, 2026
08:14
In Vitro Biochemical Assays using Biotin Labels to Study Protein-Nucleic Acid Interactions
Published on: July 17, 2019
Bacillus subtilis var. natto as a naturally optimized biotin biosensor.
Wakana Suda1,2, Yoshiaki Ohashi3, Nobuaki Kono1,4,5
1Institute for Advanced Biosciences, Keio University.
The Journal of General and Applied Microbiology
|June 28, 2026
Summary
Bacillus subtilis var. natto, a natural biotin auxotroph, can function as a microbial biosensor. This study shows its effectiveness in detecting biotin across a wide concentration range without genetic modification.
Area of Science:
- Microbiology
- Biotechnology
- Biosensor Development
Background:
- Bacillus subtilis var. natto is a naturally occurring biotin auxotroph.
- It is widely utilized in traditional soybean fermentation.
Purpose of the Study:
- To evaluate Bacillus subtilis var. natto as a microbial biosensor for biotin detection.
- To assess its performance without genetic modification.
Main Methods:
- A two-layer agar diffusion assay was employed.
- Growth responses were measured across varying biotin concentrations (0.001 to 200 mg/L).
Main Results:
- Halo diameters showed a proportional increase with biotin concentration.
- The strain detected biotin over five orders of magnitude without pathway engineering.
Conclusions:
- Bacillus subtilis var. natto serves as a simple, safe, and cost-effective biotin bioassay platform.
- Naturally evolved auxotrophic microorganisms are valuable as biosensors.
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