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Updated: May 25, 2026
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Anti-virulent Disruption of Pathogenic Biofilms using Engineered Quorum-quenching Lactonases
Published on: January 1, 2016
[Quorum-sensing behavior of Lactobacillus paracasei HD1.7]
Jingping Ge1, Baozhu Fang, Tingting Yuan
1Key Laboratory of Microbiology of Heilongjiang Province, Life Science College, Heilongjiang University, Harbin 150080, China. gejingping@126.com
Wei Sheng Wu Xue Bao = Acta Microbiologica Sinica
|January 21, 2012
Summary
Lactobacillus paracasei HD1.7 produces Paracin 1.7, an antibacterial compound. Its production is regulated by a quorum-sensing system, where Paracin 1.7 itself acts as the signaling molecule, auto-induced by cell density.
Area of Science:
- Microbiology
- Bacteriocin research
- Lactic acid bacteria
Context:
- Lactobacillus paracasei HD1.7 produces Paracin 1.7, a bacteriocin with antimicrobial properties.
- Understanding the regulation of bacteriocin production is crucial for its biotechnological applications.
- Quorum sensing (QS) is a cell-to-cell communication mechanism that controls gene expression in bacteria.
Purpose:
- To investigate the quorum-sensing mechanism regulating Paracin 1.7 metabolism in Lactobacillus paracasei HD1.7.
- To identify the signaling molecule involved in the QS system.
- To determine if Paracin 1.7 production is auto-induced.
Summary:
- Antibacterial activity of Lactobacillus paracasei HD1.7 was cell-density dependent, observed above a threshold OD600 of 0.8.
- A signaling molecule in the supernatant significantly influenced antibacterial activity, which decreased upon its removal.
- Paracin 1.7 was identified as the quorum-sensing signaling molecule, demonstrating auto-induction.
Impact:
- Elucidates the quorum-sensing regulation of bacteriocin production in Lactobacillus paracasei.
- Identifies Paracin 1.7 as an auto-induced quorum-sensing molecule.
- Provides insights into controlling bacteriocin synthesis for potential antimicrobial applications.
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