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Role of Moraxella catarrhalis outer membrane protein CD in bacterial cell morphology and autoaggregation

Ryoichi Saito1, Shiho Matsuoka, Yuji Fujinami

  • 1Department of Microbiology and Immunology, Graduate School of Health Care Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan. r-saito.mi@tmd.ac.jp

Research in Microbiology
|December 22, 2012
PubMed

Insights

Moraxella catarrhalis outer membrane protein CD (OMPCD) is crucial for bacterial morphology and preventing autoaggregation. Inactivating OMPCD in M. catarrhalis leads to larger cells, thinner walls, and reduced adherence to human cells.

Area of Science:

  • Microbiology
  • Bacterial Pathogenesis
  • Vaccine Development

Background:

  • Moraxella catarrhalis is a significant human respiratory pathogen.
  • Outer membrane protein CD (OMPCD) is a heat-modifiable outer membrane protein with vaccine potential.

Purpose of the Study:

  • To investigate the role of M. catarrhalis OMPCD in bacterial physiology and pathogenesis.
  • To analyze the impact of OMPCD inactivation on bacterial morphology, adherence, and autoaggregation.

Main Methods:

  • Nucleotide sequence analysis of the ompCD gene.
  • Insertional mutagenesis to create ompCD mutant strains.
  • Phenotypic characterization using microscopy and adherence assays.

Main Results:

  • ompCD mutant strains showed modest growth defects, larger cell size, and thinner cell walls.
  • Mutant strains exhibited increased autoaggregation and surface hydrophobicity.
  • Adherence to HEp-2 cells was reduced in ompCD mutant strains.

Conclusions:

  • M. catarrhalis OMPCD is vital for stabilizing cell morphology and preventing autoaggregation.
  • OMPCD influences bacterial growth, adherence to human epithelial cells, and overall pathogenesis.
  • OMPCD is a promising target for M. catarrhalis vaccine development.

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