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Updated: Aug 1, 2026
05:52
In Situ Measurement and Correlation of Cell Density and Light Emission of Bioluminescent Bacteria
Published on: June 28, 2018
Cell-density sensing: come on inside and tell us about it
1Howard Hughes Medical Institute, Department of Biochemistry and Cell Biology, Rice University, Houston, Texas 77005-1892, USA.
Current Biology : CB
|February 28, 1998
Summary
Bacillus subtilis cells decide their developmental path based on local cell density. They sense this using secreted signal peptides, with two detected via a novel transport-dependent mechanism.
Area of Science:
- Microbiology
- Cell Biology
- Biochemistry
Background:
- Cell density significantly influences microbial development.
- Bacillus subtilis exhibits complex developmental pathways.
- Signal peptide detection is crucial for microbial communication.
Purpose of the Study:
- To investigate how Bacillus subtilis senses local cell density.
- To identify the mechanisms underlying cell density sensing.
- To characterize novel signal peptide transduction pathways.
Main Methods:
- Analysis of secreted signal peptides in Bacillus subtilis.
- Investigation of signal peptide transport mechanisms.
- Characterization of a new cell density transduction system.
Main Results:
- Bacillus subtilis monitors at least three secreted signal peptides for cell density sensing.
- Two signal peptides are detected through a novel mechanism.
- This mechanism involves specific transport of signal peptides into the cell.
Conclusions:
- Local cell density is a key factor in Bacillus subtilis developmental decisions.
- A novel, transport-dependent mechanism contributes to signal peptide detection.
- This finding reveals new insights into microbial quorum sensing and development.
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