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Porphyromonas gingivalis as a Model Organism for Assessing Interaction of Anaerobic Bacteria with Host Cells
12:16

Porphyromonas gingivalis as a Model Organism for Assessing Interaction of Anaerobic Bacteria with Host Cells

Published on: December 17, 2015

In vitro environmental regulation of Porphyromonas gingivalis growth and virulence

L Kesavalu1, S C Holt, J L Ebersole

  • 1Center for Oral Health Research, College of Dentistry, University of Kentucky, Lexington, KY 40536-0305, USA. knlaks0@uky.edu

Oral Microbiology and Immunology
|June 26, 2003
PubMed

Insights

Iron availability, particularly hemin, significantly impacts Porphyromonas gingivalis virulence. Lower iron levels reduce lesion size and gingipain activity, crucial factors in periodontal disease progression.

Area of Science:

  • Microbiology
  • Oral Health
  • Infectious Diseases

Background:

  • Porphyromonas gingivalis is a key pathogen in periodontal disease, causing soft tissue destruction and inflammation.
  • Its virulence is linked to its ability to form invasive lesions and induce inflammation, as demonstrated in murine models.

Purpose of the Study:

  • To investigate the regulatory role of hemin on the growth and virulence of Porphyromonas gingivalis strains.
  • To understand how iron availability influences P. gingivalis's ability to cause disease.

Main Methods:

  • Culturing P. gingivalis strains under varying iron conditions (depleted, normal, elevated) and in the presence of blood.
  • Assessing lesion size, type, onset, and mortality in a murine abscess model.
  • Measuring gingipain enzyme activity and cell-associated iron levels.

Main Results:

  • P. gingivalis grown under iron-depleted conditions exhibited significantly smaller lesion sizes in mice.
  • Iron depletion led to statistically significant decreases in gingipain enzyme activity.
  • Elevated hemin increased cell-associated iron, enhancing survival during iron deprivation.

Conclusions:

  • Hemin availability is a critical regulator of P. gingivalis virulence.
  • Iron levels influence P. gingivalis growth, survival, gingipain production, and iron accumulation, all contributing to disease pathogenesis.

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