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Outer membrane adhesion factor multivalent adhesion molecule 7 initiates host cell binding during infection by

Anne Marie Krachler1, Hyeilin Ham, Kim Orth

  • 1Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.

Proceedings of the National Academy of Sciences of the United States of America
|June 29, 2011
PubMed

Insights

A novel multivalent adhesion molecule (MAM7) enables gram-negative pathogens to bind host cells. Targeting MAM7 could be key to combating bacterial infections.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Molecular Biology

Background:

  • Bacterial adhesion to host cells is critical for pathogen success and virulence factor delivery.
  • Gram-negative pathogens utilize specific mechanisms for initial host cell attachment.
  • Understanding these adhesion mechanisms is vital for developing anti-infective strategies.

Purpose of the Study:

  • To identify and characterize a novel adhesion molecule involved in early-stage bacterial infection.
  • To investigate the role of this molecule in pathogen virulence and host cell interaction.
  • To explore the potential of this molecule as a therapeutic target or tool against bacterial infections.

Main Methods:

  • Identification and characterization of the multivalent adhesion molecule (MAM7).
  • Analysis of MAM7's binding interactions with host cell components (fibronectin and phosphatidic acid).
  • Assessment of MAM7's necessity for virulence in a nematode infection model and its role in mammalian cell killing.
  • Expression of MAM7 in nonpathogenic bacterial strains to evaluate its potential as an anti-infective tool.

Main Results:

  • A multivalent adhesion molecule (MAM7) was identified, facilitating high-affinity binding of gram-negative pathogens to host cells.
  • MAM7 engages in both protein-protein (fibronectin) and protein-lipid (phosphatidic acid) interactions with the host cell membrane.
  • MAM7 expression is essential for pathogen virulence in a nematode model and for efficient killing of cultured mammalian cells.
  • Expressing MAM7 on nonpathogenic bacteria created a tool to impede gram-negative pathogen infection.

Conclusions:

  • MAM7 is a key molecular factor enabling gram-negative pathogens to adhere to host cells during infection.
  • The dual interaction mechanism of MAM7 highlights its importance in establishing infection.
  • Targeting or utilizing MAM7 presents a promising strategy for combating gram-negative bacterial infections.

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