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PubMed1983

Kingella (Moraxella) kingae infections in children.

Kingella (Moraxella) kingae occasionally colonizes the nasopharynx and rarely causes serious infections. Three children with K kingae infections treated over a two-month period were studied. Epidemiologic investigation concluded that infection was community acquired, not pseudoinfection or nosocomial infection. Except for prompt laboratory recognition of the organism, no identifiable factors explained the observed prevalence. Five additional K kingae infections were reviewed. Affected sites included blood (two), valves (two), bone (two), joint (one), and disk space (one). Three patients had underlying disease; one was immunosuppressed. Kingella kingae resembles other members of the Neisseriaceae family and causes similar infections except meningitis. It is differentiated by colonial characteristics and standard biochemical tests. Treated infections responded to penicillin G potassium. Gram-negative bacteria uncommonly are implicated in endocarditis, arthritis, osteomyelitis, and diskitis; K kingae deserves recognition as a pathogen in these pediatric infections.

Arthritis, Infectious↗
PubMed1978

[Sensitivity of marine bacteria to several disinfectants used in the fish processing industry. I. Homologous and heterologous resistance of Pseudomonas and Moraxella ssp].

It was shown that ability of developing resistance to QAC by Moraxella ssp. is limited, while marine strains of Pseudomonas sp. are able to develop both homological and heterological resistance to Sterinol and Laurosept. Five months storage in medium without QAC caused partial loss of resistance of strains which previously gained resistance to this compound. None of the tested marine bacteria strains was able to get resistance against Chloramina T. Strains with developed resistance to Laurosept and Sterinol became more sensitive to Chloramina T. On the other hand, as a result of contact of the same bacteria with sublethal doses of Chloramina T increase of sensitivity to QAC was observed.

Benzalkonium Compounds↗
PubMed2006

Rapid typing of Moraxella catarrhalis subpopulations based on outer membrane proteins using mass spectrometry.

Moraxella catarrhalis is a major mucosal pathogen of the human respiratory tract both in children and in adults. Two subpopulations of this organism have been described that differ in 16S rRNA gene sequence and virulence traits. Three 16S rRNA types have been defined. 2-DE followed by protein identification by MS revealed significant differences in the outer membrane protein (OMP) patterns of each M. catarrhalis 16S rRNA type. Approximately 130 features were detected on the 2-DE map of each M. catarrhalis 16S rRNA type. However, only 50 features were expressed by all strains. Furthermore, direct profiling of isolated OMP using MALDI-TOF MS resulted in a characteristic spectral fingerprint for each 16S rRNA type. Fingerprints remained identical when intact cells instead of isolated OMP were analyzed. This finding suggests that the source of desorbed ions is the outer membrane. Based on the fingerprint we were able to assign 18 well-characterized clinical M. catarrhalis isolates to the correct subpopulation. Therefore, MALDI-TOF of intact M. catarrhalis provides a rapid and robust tool for M. catarrhalis strain typing that could be applied in epidemiological studies.

Bacterial Outer Membrane Proteins↗
PubMed1994

Bronchopulmonary infection with Moraxella catarrhalis in infants requiring extracorporeal membrane oxygenation.

Moraxella (formerly Branhamella) catarrhalis is now a well-recognized pathogen of the upper and lower respiratory tract. Four pediatric cases of life-threatening pneumonia requiring extracorporeal membrane oxygenation are presented. M. Catarrhalis was isolated within 48 hours of admission in three of the cases and within 24 hours of an acute deterioration in the fourth. We conclude that M. catarrhalis is either a significant pathogen in its own right, a marker of severe disease, or a secondary invader.

Child, Preschool↗
PubMed1996

Separation and characterization of O-deacylated lipooligosaccharides and glycans derived from Moraxella catarrhalis using capillary electrophoresis-electrospray mass spectrometry and tandem mass spectrometry.

Electrophoretic methods have been developed for the analysis of complex carbohydrates derived from lipooligosaccharides (LOS) of Moraxella catarrhalis using capillary electrophoresis coupled to electrospray mass spectrometry (CE-ESMS). Separation of lipooligosaccharides (LOS) arising from mild hydrazinolysis of the intact lipopolysaccharides (LPS) was achieved using aqueous ammonium formate, and enabled identification of sites of heterogeneity (phosphates, phosphoethanolamine, and pendant acyl groups) on either the lipid A or the core oligosaccharide. More complex mixtures of carbohydrates obtained from the complete deacylation and dephosphorylation of LOS were amendable to electrophoretic conditions using both anionic and cationic separation. In particular, electrophoretic conditions were developed which permitted resolution of closely related oligosaccharides according to the number of carbohydrate residues appended to the core structure. Structural characterization of carbohydrates and LOS released from the hydrazinolysis and acid hydrolysis treatment of the intact LPS was achieved using tandem mass spectrometry (MS-MS) for samples introduced by direct flow injection. Taken together, the combination of CE-ESI-MS and MS-MS analyses provided valuable information on the heterogeneity of the LOS population in which a significant level of variability was found mostly in the lipid A portion.

Acylation↗
PubMed1996

Plasmid-mediated degradation of o-phthalate and salicylate by a Moraxella sp.

A Moraxella sp. strain VG45 capable of utilizing o-phthalate and salicylate as a sole source of carbon and energy was isolated. The degradation of o-phthalate occurs via phthalate 4,5-dioxygenase, 4,5-dihydro-4,5-dihydroxyphthalate dehydrogenase, 4,5-dihydroxyphthalate decarboxylase and protocatechuate 4,5-dioxygenase. Salicylate is degraded via salicylate 5-hydroxylase, gentisate 1,2-dioxygenase and then by a glutathione-independent maleylpyruvate hydrolase. Further, a plasmid of app. 60 kilobase pairs (kb) is involved in the degradation of the o-phthalate and salicylate and the enzymes of these two pathways are independently regulated in strain VG45.

Biodegradation, Environmental↗
PubMed1993

The interaction between human transferrin and transferrin binding protein 2 from Moraxella (Branhamella) catarrhalis differs from that of other human pathogens.

The interaction between human transferrin and the transferrin binding proteins of Moraxella catarrhalis was studied by binding and affinity isolation experiments with transferrin and its derivatives. Competition binding experiments demonstrated that, compared to transferrin binding proteins in Neisseria meningitidis, the receptors in M. catarrhalis were more effectively blocked by iron-saturated transferrin than by the apo form of the protein. A combination of direct binding experiments and affinity isolation experiments demonstrated that this was due to a strong preference for binding of iron-saturated transferrin by transferrin binding protein 2 (Tbp2). Binding and affinity isolation studies also demonstrated that the C-lobe of human transferrin was fully capable of binding to M. catarrhalis transferrin binding protein 1 (Tbp1) but not to Tbp2. Neither the N-lobe nor a proteolytic derivative of human transferrin lacking only a portion of the C-terminus were capable of effectively binding to M. catarrhalis Tbp2, possibly implicating the involvement of several regions in the binding interaction.

Amino Acid Sequence↗
PubMed1998

Biochemical and immunological properties of lactoferrin binding proteins from Moraxella (Branhamella) catarrhalis.

The Neisseriaceae can acquire iron (Fe) from lactoferrin (Lf) using host-Lf receptors on the bacterial surface. The binding proteins that are proposed to constitute the receptor have been identified by isolation with immobilized Lf. Using CopB-specific monoclonal antibodies and isogenic CopB mutants, we demonstrate that the 84 kDa protein isolated with immobilized human Lf from Moraxella catarrhalis using low stringency conditions is CopB, an 84 kDa membrane-spanning protein with similarities to other TonB-dependent outer membrane proteins. Affinity isolation of Lf receptors from a variety of M. catarrhalis strains using high stringency conditions revealed a 95 kDa protein migrating slightly faster than LbpA on SDS-PAGE in some strains. Convalescent human antisera from patients infected with M. catarrhalis reacted specifically with this protein, but not LbpA. Proteolysis experiments demonstrated that, unlike LbpA, it was rapidly degraded. The 95 kDa protein, but not LbpA, binds labelled Lf after SDS-PAGE and electroblotting, suggesting the 95 kDa protein is LbpB, the homologue of TbpB. This protein comigrates with LbpA in most strains, which may explain why it had not been previously identified.

Amino Acid Sequence↗
PubMed2000

Attachment of Moraxella catarrhalis occurs to the positively charged domains of pharyngeal epithelial cells.

Attachment of bacteria to host cells is the initial step in the pathogenesis of infection. Several factors, such as hydrophobicity, surface electric charge, and van der Waals force, are considered to be responsible for the attachment step. However, it is not clear why bacteria and epithelial cells, both of which possess a negative surface charge, do not repel one another. In the present study, we used Moraxella catarrhalis and pharyngeal epithelial cells to study the surface charges of structures involved in the attachment. By atomic force microscopy (AFM) equipped with surface potential spectroscopy, it was found that the cell surface microplicae have a positive charge of 30.1+/-3.6 mV (mean+/-SE). The depressions between the microplicae have a negative surface charge of 43.5+/-4.0 mV. Using cationic ferritin and electron microscopy (EM) we confirmed that the depressions between the microplicae have a negative charge. By AFM and by using cationic ferritin with EM, it was found that the net surface charge of the bacterial cells is negative. By both AFM and EM, it was found that the bacterial cells attach to the microplicae of the pharyngeal epithelial cell. Our work confirmed the general belief that both kinds of cells do have a net negative charge. We conclude that there are positively and negatively charged domains on the surface of human pharyngeal epithelial cells. M. catarrhalis evidently attaches to the positively charged domain (i.e. microplicae) of pharyngeal epithelial cells.

Adult↗
PubMed1999

Structural analysis of plasmid pLQ510 from Moraxella catarrhalis E22.

The complete nucleotide sequence of plasmid pLQ510 from Moraxella catarrhalis strain E22 has been determined. This plasmid contained 12,082 bp with 38% GC content. Five open reading frames that encoded predicted proteins with homology to plasmid-encoded proteins from other bacteria were identified. A putative origin of replication that contained an AT-rich region followed by four direct repeats and an inverted repeat was identified.

Amino Acid Sequence↗
PubMed1980

Chemical composition and ultrastructure of cellular and extracellular Moraxella glucidolytica lipopolysaccharides.

A cellular (LPS I) and extracellular (LPS II) lipopolysaccharide were isolated from Moraxella glucidolytica cells grown on ethanol and from the culture fluid, respectively. Both LPS were toxic when injected to mice and chick embryos. These LPS contained glucose, galactose, glucosamine, galactosamine, 2-keto-3-deoxyoctonate and lipids. By permethylation studies, glucose was found to be linked (1 lead to 6) and (1 lead to 3) in LPS I and only (1 lead to 6) in LPS II. Galactose was the terminal non-reducing sugar. Branching occurred at positions 3 and 4 of galactose residues. LPS I was rich in alpha- and beta-hydroxylauric and alpha-hydroxymyristic acids and LPS I was detoxified by mild acid and alkaline treatments. It was also dissociated by sodium deoxycholate and chromatographed on Sephadex G-75. The main fraction was reassociated by removing the surfactant by dialysis. The morphology of LPS I and LPS II was examined by electron microscopy. LPS I (original and reassociated fractions) consisted exclusively of ribbons while LPS II contained ribbons and vesicles.

Bacterial Toxins↗
PubMedDate not supplied

Evidence of lectin-mediated adherence of Moraxella catarrhalis.

Clinical isolates of Moraxella catarrhalis (n = 86) were evaluated for their haemagglutinating activity with different types of erythrocytes. Of all the isolates tested, 12 did not agglutinate with any of the erythrocytes, whereas 65 reacted with human erythrocytes of type A, B, and 0, and 26 with erythrocytes from rabbit, guinea pig, dog, or rat. None of the isolates agglutinated with sheep and goat erythrocytes. The agglutination titres ranged from 0 to 64. Among these isolates, 13 different agglutination patterns could be distinguished. The agglutinating activity was Ca(2+)-dependent and was inhibited by proteases, by temperatures exceeding 50 degrees C and by the addition of D-glucosamine or D-galactosamine. The adherence capacity of the M. catarrhalis isolates to tracheal epithelium correlated with their agglutination titre and could be inhibited by the same treatments. These data provide strong evidence that adherence of M. catarrhalis is mediated by lectins located on the bacterial surface.

Adhesins, Bacterial↗
PubMedDate not supplied

Moraxella catarrhalis in upper respiratory tract of healthy Yemeni children/adults and paediatric patients: detection and significance.

A highly variable carriage rate of Moraxella catarrhalis has been reported in the literature. In order to assess the reasons for this variability, detection rates of this organism from various sites of the upper respiratory tract of children and adults were studied. Throat swabs, oral swabs and nasal swabs from 131 children, 96 adults and 64 paediatric patients with upper respiratory tract infections were cultured on a selective medium. Detection rates of 31.4% in children less than three years of age, 38.5% in children between 4 and 12 years, 11.7% in adults and 21.9% in patients were found, respectively. The reasons for high variability in the carriage rates were many including the number and site of specimen collection, media used for isolation and identification criteria. All isolates were sensitive to amoxycillin-clavulanic acid and co-trimoxazole. A significantly higher share of M. catarrhalis isolates from patients were beta-lactamase producers (12/14, 85.7%) as compared to normal healthy subjects (41.9%), suggesting a cautious approach in the use of beta-lactam antibiotic in respiratory tract infections.

Administration, Oral↗
PubMed1992

Killing kinetics of five orally administered antibiotics at clinically achievable concentrations against Moraxella catarrhalis.

Time-kill kinetic studies were used to measure the bactericidal activity of amoxicillin/clavulanic acid (in a new form for pediatric use), cefaclor, cefuroxime, cefixime and erythromycin against 30 beta-lactamase producing Moraxella catarrhalis strains. Antibiotics were tested at the mean maximum serum concentration observed after administration of a standard dose and at 0.5 x Cmax, 0.33 x Cmax and 0.25 x Cmax. A 2 log10 reduction in colony counts was obtained with the Cmax of amoxicillin/clavulanic acid and cefixime after 5 h of incubation. After 24 h of incubation a decrease of 3 and 4 log was observed with cefixime and amoxicillin/clavulanic acid respectively. At 0.5 x Cmax and 0.33 x Cmax, bactericidal activity was obtained only with amoxicillin/clavulanic acid.

Amoxicillin↗
PubMed1990

Superoxol and aminopeptidase tests for identification of pathogenic Neisseria species and Moraxella (Branhamella) catarrhalis.

The superoxol test, and prolyl aminopeptidase and gammaglutamyl aminopeptidase tests were evaluated for the detection of pathogenic Neisseria spp. using 317 strains of Neisseria-ceae. The superoxol test was positive for all 116 gonococci and 62 Moraxella (Branhamella) catarrhalis strains, but also for three strains of Neisseria meningitidis, one strain of Neisseria lactamica and eight saprophytic neisseriae. When using strains grown on Thayer-Martin medium, the positive and negative predictive values of the superoxol test for the identification of Neisseria gonorrhoeae were 96.7% and 100% respectively. Meningococci were the only neisseriae growing on Thayer-Martin medium that showed gamma-glutamyl aminopeptidase activity. The prolyl aminopeptidase test showed low specificity.

Aminopeptidases↗
PubMed1987

Characterization of the submerged growth of Moraxella bovis.

A submerged batch cultivation of Moraxella bovis in a medium containing enzymic casein hydrolyzate and supplemented with dialyzed ram blood was described. Up to the growth limitation the bacteria grew exponentially without a lag phase and with a doubling period of 64 min. During the exponential phase no significant decrease of viable cells and cell autolysis were observed. Amino acids were the limiting factor. At the end of growth glutamic acid, threonine and serine were detected at the lowest concentrations. Substrate limitation led to an irreversible decrease of the metabolic activity. Growth yield on oxygen was 2.3 X 10(9) cells per mg O2. The fraction of respiration required for growth-uncoupled processes was negligible. During the cultivation ammonia was produced and the pH increased but it was not the inhibitory factor. Respiration was not limited by oxygen at concentrations higher than 0.63 mumol O2 per L. Sufficient pili were produced.

Culture Media↗
PubMed1992

Growth curves of Staphylococcus aureus, Candida albicans, and Moraxella osloensis in propofol and other media.

Propofol, 2,6 diisopropylphenol, in an emulsion formulation (Diprivan), has been associated with postsurgical infections caused by Staphylococcus aureus, Moraxella osloensis and Candida albicans. These organisms were individually inoculated into each of the following media: (1) the emulsion preparation of propofol, (2) Intralipid 10%, (3) pure 2,6 diisopropylphenol, and (4) trypticase soy broth (TSB). The organisms were incubated and subcultured hourly for eight hours at room temperature. Propofol supported the growth of all three organisms, but for S. aureus and M. osloenis, the growth rate was slower in propofol than in TSB (P less than 0.05). There was no difference between the growth rate of any organism in propofol than in Intralipid 10%. The authors conclude that propofol, in the emulsion formulation, supports bacterial growth and, therefore, must be prepared for administration in an aseptic manner. Also, by administering propofol soon after preparation, the risk of introduction of a significant inoculum to the patient will be reduced.

Candida albicans↗
PubMed1997

[Moraxella catarrhalis: virulence and resistance mechanisms].

It is more than a century ago that Moraxella catarrhalis was discovered and described in some detail. However, it was not until the last decade that M. catarrhalis was recognized as a facultative pathogen, namely in otitis media (predominantly in children), sinusitis and nosocomial pneumonia in the group of elderly, debilitated patients. Liberation of endotoxin, histamine, and chemotactically active factors can be considered the major pathogenicity factors. The pathogen can protect itself, on the one hand by binding of the Clq subcomponent of the complement system followed by subsequent formation of a functionally inactive complex with Cl, and on the other hand by inactivation of the terminal (lytic) complement complexes by means of a specific protein on the surface of the outer cell wall. Routine diagnostic procedures require, above all, culture of the pathogen: up to now the detection of specific IgA-antibodies has not been routinely available. More than half of the clinical isolates are known to exhibit beta-lactamase production (BRO-enzymes). This is the reason why combinations of a penicillin compound with a beta-lactamase inhibitor, the group of the newer cephalosporins (including the orally active ones), doxycycline and the macrolides are therapeutically effective.

Adult↗