Analysis of Moraxella catarrhalis by DNA Typing: Evidence for a Distinct Subpopulation Associated with Virulence Traits

• Published in: The Journal of infectious diseases Vol. 181; no. 4; pp. 1376 - 1387
• Main Authors: Bootsma, Hester J., van der Heide, Han G. J., van de Pas, Simone, Schouls, Leo M., Mooi, Frits R.
• Format: Journal Article
• Language: English
• Published: Chicago, IL The University of Chicago Press 01.04.2000; University of Chicago Press; Oxford University Press
• Subjects: Adult; Antigens, Bacterial - genetics; Antigens, Surface - genetics; Bacterial Outer Membrane Proteins - genetics; Bacteriology; Base Sequence; Biological and medical sciences; Carrier State; Child; DNA; DNA fingerprinting; Epithelial cells; Fundamental and applied biological sciences. Psychology; Gels; Humans; Laryngitis - microbiology; Lung Diseases, Obstructive - genetics; Lung Diseases, Obstructive - microbiology; Major Article; Microbiology; Molecular Sequence Data; Moraxella; Moraxella (Branhamella) catarrhalis - classification; Moraxella (Branhamella) catarrhalis - genetics; Moraxella (Branhamella) catarrhalis - pathogenicity; Moraxella catarrhalis; Neisseriaceae Infections - genetics; Neisseriaceae Infections - microbiology; Pathogenicity, virulence, toxins, bacteriocins, pyrogens, host-bacteria relations, miscellaneous strains; Pharynx; Polymerase chain reaction; Polymorphism, Restriction Fragment Length; Respiratory Tract Infections - microbiology; RNA, Ribosomal, 16S - chemistry; Sputum; Virulence; Pathogenicity; Typing; Neisseriaceae; Molecular epidemiology; Bacteria; Micrococcales; Genotype; Branhamella catarrhalis; Adhesion
• ISSN: 0022-1899; 1537-6613
• DOI: 10.1086/315374

Two DNA typing methods, probe-generated restriction fragment length polymorphism analysis and single-adapter amplified fragment length polymorphism analysis, were used to study the genetic relationships among 90 Moraxella catarrhalis strains. Both methods were found to be highly concordant, generating a dendrogram with 2 main branches. The division of the M. catarrhalis population into 2 subspecies was supported by analysis of the 16S rRNA sequences. Both β-lactamase—positive and β-lactamase—negative strains were found in all main branches, suggesting horizontal transfer of the β-lactamase gene. In contrast, 2 virulence traits, complement resistance and adherence to epithelial cells, were strongly associated with 1 of the 2 subspecies. The branch depth suggested that complement-resistant adherent strains diverged from a common ancestor more recently than did complement-sensitive nonadherent strains. These findings suggest the existence of subpopulations of M. catarrhalis that differ in virulence, and they may have implications for vaccine development.