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Updated: May 31, 2026
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Biomimetic Materials to Characterize Bacteria-host Interactions
Published on: November 16, 2015
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.
Summary
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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