Moraxella catarrhalis
From DrugPedia: A Wikipedia for Drug discovery
Moraxella catarrhalis
It is a Gram-negative, aerobic, oxidase-positive diplococcus that may both colonize and cause respiratory tract-associated infection in humans.
| Kingdom | Bacteria |
|---|---|
| Phylum | Proteobacteria |
| Class | Gammaproteobacteria |
| Order | Pseudomonadales |
| Family | Moraxellaceae |
| Genus | Moraxella |
| Species | M. catarrhalis |
| Binomial | Moraxella catarrhalis |
Contents |
Surface Characteristics
The LOS consists of an oligosaccharide and lipid A and is similar to the lipopolysaccharide (LPS) of gramnegative enteric pathogens, but it lacks the O-antigenic side chain of repeating units characteristic of classical LPS. The oligosaccharide part consists of the following residues : α-D-Galp-(1-->4)-β-D-Galp-(1-->4)-α-D-Glcp-(1-->2)-β-D-Glcp-(1-->6)-α-D-Glcp [branched to α-D-GlcpNAc-(1-->2)-β-D-Glcp-(1-->4)] and [branched to β-D-Glcp-(1-->3)] -(1-->5)-Kdo[ branched to Kdop-(2-?)]
Pathogenic Activity
These bacteria are known to cause otitis media, bronchitis, sinusitis, and laryngitis. Elderly patients and long-term heavy smokers with chronic pulmonary disease should be aware that M. catarrhalis is associated with bronchopneumonia, as well as exacerbations of existing chronic obstructive pulmonary disease (COPD).
Virulence
Lipooligosaccharide is considered one possible virulence factor. The great majority of clinical isolates of this organism produce beta-lactamases and are resistant to penicillin. Resistance to trimethoprim, trimethoprim-sulfamethoxazole (TMP-SMX) and tetracycline have been reported. It is susceptible to fluoroquinolones, most second and third generation cephalosporins, erythromycin and amoxicillin-clavulanate.
