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Spatiotemporal interplay between cAMP-CRP and KdgR regulates virulence in Pectobacterium carotovorum
1Department of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea.
Microbiological Research
|July 23, 2026
Summary
Pectobacterium carotovorum coordinates virulence using carbon availability signals. The cAMP-CRP system drives spatial gene expression, prioritizing motility for expansion and tissue degradation.
Area of Science:
- Microbial Pathogenesis
- Bacterial Physiology
- Plant-Microbe Interactions
Background:
- Phytopathogens face diverse environments during infection.
- Metabolic cues, like carbon availability, influence bacterial virulence.
- Mechanisms coordinating virulence traits with metabolic signals are not fully understood.
Purpose of the Study:
- Investigate the regulatory network of Pectobacterium carotovorum during Napa cabbage colonization.
- Map the spatiotemporal expression of virulence genes in response to chemical gradients within necrotic lesions.
- Elucidate the role of carbon-responsive systems in coordinating virulence.
Main Methods:
- Utilized GFP transcriptional fusions to monitor gene expression in planta.
- Analyzed spatiotemporal gene profiles across necrotic lesions.
- Disrupted key regulatory systems (cAMP-CRP, KdgR) to assess their roles.
Main Results:
- Identified distinct chemical zonation (glucose, pectin) within lesions mirroring virulence gene expression.
- Demonstrated glucose-responsive upregulation of flagellar genes and rsmA at lesion margins via cAMP-CRP.
- Showed that cAMP-CRP disruption abolished spatial organization and impaired lesion expansion.
Conclusions:
- The interplay between cAMP-CRP and KdgR orchestrates a sophisticated spatiotemporal program for Pectobacterium virulence.
- cAMP-CRP is central to infection dynamics, prioritizing motility for expansion.
- Carbon-responsive networks enable pathogens to exploit host tissue chemical landscapes.
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