The respiratory pathogen moraxella catarrhalis binds to laminin via ubiquitous surface proteins A1 and A2

J Infect Dis. 2006 Aug 15;194(4):493-7. doi: 10.1086/505581. Epub 2006 Jul 7.


Moraxella catarrhalis is one of the leading causes of exacerbations in chronic obstructive pulmonary disease (COPD). In the present article, we show that moraxella (n=15) binds to the major basement-membrane glycoprotein laminin, which is thickened in the airways of smokers. Using clinical strains of M. catarrhalis and their corresponding ubiquitous surface protein (Usp) A1/A2 mutants, we demonstrate that UspA1 and UspA2 are important for the laminin interaction. Binding assays with recombinant proteins demonstrated that the binding regions are localized within the N-terminal fragments, where both proteins form a globular head. Thus, UspA1/A2-dependent interactions with laminin might promote bacterial adhesion, particularly in smokers with COPD.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Adhesion / physiology
  • Bacterial Outer Membrane Proteins / physiology*
  • Humans
  • Laminin / physiology*
  • Moraxella catarrhalis / pathogenicity
  • Moraxella catarrhalis / physiology*
  • Moraxellaceae Infections / complications*
  • Moraxellaceae Infections / microbiology
  • Pulmonary Disease, Chronic Obstructive / complications*
  • Pulmonary Disease, Chronic Obstructive / microbiology
  • Smoking / adverse effects


  • Bacterial Outer Membrane Proteins
  • Laminin
  • UspA protein, Moraxella catarrhalis