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Updated: Jul 19, 2026

Imaging InlC Secretion to Investigate Cellular Infection by the Bacterial Pathogen Listeria monocytogenes
14:05

Imaging InlC Secretion to Investigate Cellular Infection by the Bacterial Pathogen Listeria monocytogenes

Published on: September 19, 2013

Structure of internalin C from Listeria monocytogenes

Amy Ooi1, Syeed Hussain, Arefeh Seyedarabi

  • 1School of Biological and Chemical Sciences, Queen Mary, University of London, Mile End Road, London E1 4NS, England.

Acta Crystallographica. Section D, Biological Crystallography
|October 24, 2006
PubMed

Insights

The crystal structure of internalin C (InlC) from Listeria monocytogenes reveals unique features. These structural insights may explain InlC

Area of Science:

  • Microbiology
  • Structural Biology
  • Infectious Diseases

Background:

  • Internalins are key virulence factors in Listeria monocytogenes.
  • Internalin C (InlC) is implicated in bacterial infection but its receptor interactions remain unclear.
  • Pathogenic Listeria strains possess the inlC gene, which is co-regulated with other virulence factors.

Purpose of the Study:

  • To determine the crystal structure of internalin C (InlC).
  • To elucidate the structural basis for InlC's role in Listeria pathogenesis.
  • To compare the structural features of InlC with other internalins involved in receptor binding.

Main Methods:

  • X-ray crystallography was used to determine the 3D structure of InlC.
  • Structural analysis focused on the leucine-rich repeat (LRR) and Ig-like domains.
  • Bioinformatic and comparative structural analyses were performed.

Main Results:

  • The crystal structure of InlC was resolved to 2.0 Å resolution.
  • InlC's LRR domain exhibits a smaller, flatter, and more hydrophilic receptor-binding surface compared to internalins A and B.
  • The fused Ig-like domain of InlC possesses surface aromatic residues with potential functional significance.

Conclusions:

  • The structural characteristics of InlC's LRR domain suggest potential weak or transient receptor interactions, explaining the lack of a known receptor.
  • The Ig-like domain's surface aromatics may mediate interactions with bacterial surfaces or host receptors.
  • Understanding InlC's structure provides insights into Listeria monocytogenes virulence mechanisms.

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