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Updated: May 9, 2026
08:33
Kinetic Visualization of Single-Cell Interspecies Bacterial Interactions
Published on: August 5, 2020
Interspecies communication among commensal and pathogenic streptococci
Laura C Cook1, Breah LaSarre, Michael J Federle
1Center for Pharmaceutical Biotechnology, Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, Chicago, Illinois, USA.
Mbio
|July 25, 2013
Summary
Bacteria communicate using quorum sensing (QS) peptides. This study reveals bidirectional QS signaling between Group A Streptococcus (GAS), Group B Streptococcus (GBS), and Streptococcus dysgalactiae, suggesting inter-pathogen communication.
Area of Science:
- Microbiology
- Bacterial communication
- Pathogenesis
Background:
- Quorum sensing (QS) regulates bacterial behaviors like virulence and biofilm formation.
- Streptococci use Rgg-type proteins and short hydrophobic peptides (SHPs) for QS.
- Previous studies identified SHP2/3 and their regulators Rgg2/3 in Group A Streptococcus (GAS).
Purpose of the Study:
- To investigate quorum sensing (QS) systems in Group B Streptococcus (GBS).
- To explore interspecies communication between pathogenic streptococci.
- To understand the role of QS in the transition between carrier and pathogenic states.
Main Methods:
- Utilized isogenic mutant strains and transcriptional reporters.
- Confirmed the RovS/SHP1520 QS circuit in GBS.
- Performed in vitro experiments to assess interspecies signaling.
Main Results:
- Confirmed the RovS/SHP1520 quorum sensing (QS) circuit in GBS.
- Demonstrated that GBS peptides can modulate GAS gene expression, and vice versa.
- Identified a similar Rgg2/SHP2 system in Streptococcus dysgalactiae subsp. equisimilis, capable of signaling with both GAS and GBS.
Conclusions:
- This is the first report of bidirectional signaling between streptococcal species.
- Orthologous Rgg/SHP systems likely mediate interspecies communication among human pathogens.
- QS signaling may link the carrier and pathogenic states in streptococci.
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