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Updated: Oct 2, 2026

From Constructs to Crystals – Towards Structure Determination of β-barrel Outer Membrane Proteins
09:55

From Constructs to Crystals – Towards Structure Determination of β-barrel Outer Membrane Proteins

Published on: July 4, 2016

Crystal structure of the OpcA integral membrane adhesin from Neisseria meningitidis

Stephen M Prince1, Mark Achtman, Jeremy P Derrick

  • 1Department of Biomolecular Sciences, University of Manchester Institute of Science and Technology, Sackville Street, Manchester M60 1QD, United Kingdom.

Proceedings of the National Academy of Sciences of the United States of America
|March 14, 2002
PubMed

Insights

The outer membrane protein OpcA from Neisseria meningitidis, crucial for pathogen adhesion, has a unique beta-barrel structure. This structure reveals a crevice likely involved in binding proteoglycans, explaining how the bacteria attach to host cells.

Area of Science:

  • Structural biology
  • Microbiology
  • Pathogen adhesion mechanisms

Background:

  • Neisseria meningitidis causes meningitis and septicemia.
  • OpcA is an outer membrane protein essential for N. meningitidis adhesion.
  • Adhesion involves binding to vitronectin and proteoglycan receptors.

Purpose of the Study:

  • Determine the crystal structure of OpcA.
  • Elucidate the molecular basis of OpcA-mediated adhesion.

Main Methods:

  • X-ray crystallography
  • High-resolution structure determination (2.0 A)

Main Results:

  • OpcA features a 10-stranded beta-barrel structure.
  • Extensive loops protrude from the barrel.
  • An unusual loop conformation blocks potential pore formation.
  • A crevice formed by loops 1-5 is lined with positive charges, suggesting a proteoglycan binding site.

Conclusions:

  • The OpcA structure provides a molecular model for proteoglycan binding.
  • This mechanism is key to N. meningitidis adhesion to host cells.
  • Understanding OpcA structure aids in developing strategies against meningococcal disease.

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