Moraxella strain

Streptococcus pneumoniae is the most common cause of acute otitis media (20% to 35%). Nontypable strains of Haemophilus influenzae and Moraxella catarrhalis are each responsible for 20% to 30% and 20% of cases, respectively. In 44% of cases, a viral etiology is found with or without concomitant bacteria. 

S pneumoniae, S aureus, H influenzae, Moraxella catarrhaiis, mycoplasmas, Legionella, Chlamydia, H pylori, N gonorrhoeae, fragilis, T gondii, and nontuberculosis mycobacteria. Many macrolide-resistant strains are susceptible to ketolides because the structural modification of these compounds renders them poor substrates for efflux pump-mediated resistance and they bind to ribosomes of some bacterial species with higher affinity than macrolides. 

A combination of trimethoprim-sulfamethoxazole is effective treatment for a wide variety of infections including P jiroveci pneumonia, shigellosis, systemic salmonella infections, urinary tract infections, prostatitis, and some nontuberculous mycobacterial infections. It is active against most Staphylococcus aureus strains, both methicillin-susceptible and methicillin-resistant, and against respiratory tract pathogens such as the pneumococcus, Haemophilus sp, Moraxella catarrhalis, and Klebsiella pneumoniae (but not Mycoplasma pneumoniae). However, the increasing prevalence of strains of E coli (up to 30% or more) and pneumococci that are resistant to trimethoprim-sulfamethoxazole must be considered before using this combination for empirical therapy of upper urinary tract infections or pneumonia. 

Moraxella catarrhalis is also known in the literature as Branhamella catarrhalis and type strains are available from the ATCC or clinical microbiology laboratories may provide clinical isolates. It is strongly recommended that a biohazard safety hood is used when handling large quantities of the bacterium (see Note 3). 

Moraxella (previously Branhamella) catarrhalis, a commensal of the oropharynx, may be a pathogen in patients with chronic bronchitis because many strains produce 3-lactamase, co-amoxiclav or erythromycin/clarithromycin should be used. 

In an in vitro study, ciprofloxacin, grepafloxacin, levo-floxacin, moxifloxacin, ofloxacin, and sparfloxacin had similar good activity against Haemophilus influenzae and Moraxella catarrhalis (112). Against S. pneumoniae (irrespective of the strain s susceptibility to penicillin), grepafloxacin, levofloxacin, moxifloxacin, and sparfloxacin had better activity than ciprofloxacin and ofloxacin. 

There are a number of methods in use that directly detect the production of antimicrobial resistance in pathogens. /3 -Lactamase production can be detected rapidly and easily in the clinical laboratory with the use of nitrocephin disks. Nitrocephin is a chromogenic cephalosporin derivative that changes color on hydrolysis by /3-lactamase. Colonies from a growing bacterial culture can be touched to a disk, with /S-lactamase production noted within a few minutes. Although rapid and reliable, this method is limited to the assessment of strains of staphylococci, enterococci, H. influenzae, Moraxella catarrhalis, and N. gorwrrhoeae. The nitrocephin disk also cannot detect /3-lactam... 

Nitrophenols — Monooxygenation is involved in the degradation of 4-nitrophenol by a strain of Moraxella sp. (Spain and Gibson 1991), and the enzyme appears to be a particulate flavoprotein. In the Gram-positive organisms Arthrobacter sp. (Jain et al. 1994) and Bacillus sphaericus strain JS905... 

Cefaclor is used orally. The concentration in plasma after oral administration is about 50% of that achieved after an equivalent oral dose of cephalexin. However, cefaclor is more active against H. influenzae and Moraxella catarrhalis, although some P-lactamase-producing strains of these organisms may be resistant. 

Among these fluorinated derivatives, 21 showed the most promising features of antimicrobial activity in vivo, pharmacokinetics, and clinical efficacy [51-54], The in vitro activity of 21 against pathogens of respiratory tract infections was compared with that of 1. The activity of 21 and 1 were tested against S. aureus (16 strains). Streptococcus pneumoniae (24), Streptococcus pyogenes (24), Moraxella catarrhalis (22), and H. influenzae (22), and the observed MIC50 values (pg/ml) were 0.5 and 0.25,0.03 and 0.03,0.125 and 0.03,0.125 and 0.06, and 2 and 4, respectively. 

Biedenbach, D. J., Barrett, M. S., and Jones, R. N. (1998). Comparative antimicrobial activity and kill-curve investigations of novel ketolide antimicrobial agents (HMR 3004 and HMR 3647) tested against Haemophilus influenzae and Moraxella catarrhalis strains. Diagn. Microbiol. Infect. Dis. 31, 349 —353. 

Beta-lactamase production by strains of Haemophilus influenzae, Moraxella catarrhalis, and Neisseria gonorrhoeae confers resistance against penicillin G. Which one of the following antibiotics is most likely to be effective against all strains of each of the above organisms ... 

Kawasaki, H., N. Tone and K. Tonomura. Purification of properties of haloacetate halldohydrolase specified by plasmid from Moraxella sp strain B. Agrlc. Biol. Chem. 45 35-42. 

Morgan, M.G., McKenzie, H., Enright, M.C., Bain, M., and Emmanuel, F.X. 1992, Use of molecular methods to characterize Moraxella catarrhalis strains in a suspected outbreak of nosocomial infection. Eur J Clin Microbiol Infect Dis 11 305-312. 

Figure 14. Proposed pathway of Propachlor degradation by strains DAKS and MAB2 of Moraxella and Xanthobacter, respectively [234].

---