Complement-resistant Moraxella catarrhalis forms a genetically distinct lineage within the species
van der Plas, J.
van Dijk, H.
van Belkum, A.
Centraal Instituut voor Voedingsonderzoek TNO
Moraxella catarrhalis is a bacterial species that has been implicated in 15^20% of all cases of otitis media in the USA and the complementresistantvariant of M. catarrhalis has been considered particularly pathogenic. A collection of geographically diverse, complement-sensitive (n = 28) and -resistant strains (n = 47) of M. catarrhalis was assembled in order to analyse the bacterial population structure. All strains were identified as M. catarrhalis by conventional microbiological and biochemical methods. Amplification of the small subunit (ssu) ribosomal RNA gene followed by restriction fragment length polymorphism (RFLP) analysis did not reveal consistent differences between serumsusceptible and -resistant M. catarrhalis isolates. Interestingly, upon automated ribotyping using the Qualicon RiboPrinter0 microbial characterisation system, the complement-sensitive and -resistant strains segregated into two groups. This suggested the existence of two clearly distinguishable lineages within the species M. catarrhalis. This observation was corroborated by pulsed field gel electrophoresis (PFGE) of DNA macro-restriction fragments, a non-ribosomal PCR RFLP procedure and random amplification of polymorphic DNA (RAPD) analysis. All procedures grouped the two variants similarly. Redefinition of the taxonomic status of complement-resistant M. catarrhalis or even the definition of a new species may be opportune. Chemicals/CAS: Complement System Proteins, 9007-36-7; DNA, Bacterial; DNA, Ribosomal
To reference this document use:
Pulsed field gel electrophoresis
Polymerase chain reaction
Random amplified polymorphic DNA
Restriction fragment length polymorphism
Bacterial Typing Techniques
Complement System Proteins
Electrophoresis, Gel, Pulsed-Field
Moraxella (Branhamella) catarrhalis
Polymorphism, Restriction Fragment Length
Random Amplified Polymorphic DNA Technique
Fems Microbiology Letters, 184 (1), 1-8