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PubMed1990

Antibiotic susceptibilities and drug resistance in Moraxella (Branhamella) catarrhalis.

PURPOSE: To summarize current knowledge of drug susceptibility and mechanisms of drug resistance in Moraxella (Branhamella) catarrhalis. MATERIALS AND METHODS: The current medical literature was reviewed, with careful attention to recent studies of the BRO beta-lactamases. RESULTS: Although intrinsically resistant to a small group of drugs that included vancomycin and trimethoprim, acquired drug resistance in Branhamella catarrhalis was unknown in the early years of antimicrobial therapy. During 1976 to 1977, however, two previously unrecognized beta-lactamases appeared in this species almost simultaneously around the world. At the same time these enzymes, now known as BRO-1 and BRO-2, also appeared in two closely related commensal species of Moraxella. Within four years the BRO enzymes were found in up to 75 percent of B. catarrhalis in the United States where they provide low-level resistance to penicillin and ampicillin but not to most cephalosporins. The BRO genes appear to be chromosomal but are readily transferred by conjugation within the Moraxella genus. Resistance to aminoglycosides and trimethoprim-sulfamethoxazole has been reported from Spain, and resistance to both erythromycin and tetracycline has recently been described among United States isolates of B. catarrhalis. CONCLUSION: Despite this drug resistance, numerous oral and parenteral agents are available and appear useful for treatment of clinical disease, including amoxicillin/clavulanic acid, erythromycin, the tetracyclines, ciprofloxacin, and trimethoprim/sulfamethoxazole. Recent changes in drug resistance in this species suggest that continued monitoring of drug resistance in B. catarrhalis is needed.

Anti-Bacterial Agents↗
PubMed1990

Production of paralytic shellfish toxins by a bacterium Moraxella sp. isolated from Protogonyaulax tamarensis.

A bacterium Moraxella sp. isolated from Protogonyaulax tamarensis was cultured in various conditions. Changes of toxicity and toxin components of the cells during culture were analyzed by bioassay and HPLC-fluorometric analysis. Toxin productivity of Moraxella sp. increased when it was cultured in nutrition-deficient environments. The main toxins produced by Moraxella sp. in these conditions were gonyautoxins (GTXs), mainly GTX 1 and 4 which are major toxins of P. tamarensis.

Animals↗
PubMedDate not supplied

Central venous catheter infection caused by Moraxella osloensis in a patient receiving home parenteral nutrition.

We report the first case of a central venous catheter infection caused by Moraxella osloensis, which was successfully treated without catheter removal. The isolation, identification, and pathogenesis of this species are discussed. It is recommended that Moraxella isolates be identified to species in order to determine the relative pathogenic and opportunistic roles of the various Moraxella species. Our case also demonstrates that catheter sepsis caused by some Gram-negative organisms may be amenable to systemic antibiotic therapy without the necessity of catheter removal.

Aged↗
PubMedDate not supplied

Nasopharyngeal colonization by Moraxella catarrhalis and study of antimicrobial susceptibility in healthy children from Cuban day-care centers.

The prevalence of nasopharyngeal carriage of Moraxella catarrhalis was determined for the first time in Cuba. One-hundred fifty healthy children attending three day-care centers in the municipality of Marianao, Havana City were studied. The percentage of recovering bacteria in nasal and pharyngeal swabs was compared. Antimicrobial susceptibilities to ampicillin, trimethoprim-sulfamethoxazole, tetracycline, cefotaxime, ceftriaxone, chloramphenicol, erythromycin, azithromycin, amoxicillin/clavulanate, and norfloxacin were determined by the disk diffusion method according to recommendations of the National Committee for Clinical Laboratory Standards. Sixty-five percent of the children studied carried Moraxella catarrhalis. The nasal cavity was the main isolation site for this organism (81% of positive cultures). Most strains were highly susceptible to the antimicrobial agents tested, except to ampicillin (53.6% resistance). This study provides evidence of the need for continued surveillance of antimicrobial susceptibility of Moraxella catarrhali, in order to determine optimal empiric therapy for community-acquired respiratory tract infections produced by this pathogen.

Anti-Bacterial Agents↗
PubMed2000

Report of a case of bronchopneumonia associated with Moraxella bovis isolation in a chamois (Rupicapra pyrenaica).

A case of fibrinopurulent bronchopneumonia associated with Moraxella bovis infection in a chamois (Rupicapra pyrenaica) is described. The animal, a 4-month-old female, was referred by the staff warden of the National Game Reserve of Freser-Setcases (Catalonia, north-eastern Spain). The animal was in good general condition and was found 4 h before death. On necropsy the lungs were congested and oedematous, with haemorrhagic areas in the cranial and middle lobes. The microscopic lesions were those of a fibrinopurulent bronchopneumonia. Microbiological study of the samples obtained showed numerous small beta-haemolytic colonies in pure culture, identified as Moraxella (Moraxella) bovis.

Animals↗
PubMed2000

Adaptive bone modeling and remodeling in acute otitis media caused by non-typeable or type B Haemophilus influenzae or Moraxella catarrhalis.

Experimental studies have shown that acute otitis media caused by Streptococcus pneumoniae alters modeling dynamics in bone tissue structures surrounding the middle ear cavity. Initial resorption of bone is followed by formative activity, seen as massive osteoneogenesis. However, neither resorptive nor formative activity occurs in the otic capsule, supporting the existence of a perilymphatic zone of specialized bone. This study investigates adaptive bone modeling in acute otitis media caused by other bacteria frequently encountered in this disease. Seventy-five rats were inoculated with either non-typeable or type b Haemophilus influenzae, or Moraxella catarrhalis (25 rats in each group). Five rats from each group were sacrificed on days 4, 8, 16, 60 and 180 post-inoculation. Qualitative as well as quantitative histopathology revealed increasing apposition of new bone on both sides of the original bony wall of the middle ear bulla, i.e. at the inner and outer periosteum. Remodeling activity was seen on later days of sacrifice, as typical osteone (Haversian system) formation. Measured bone thickness in four anatomically well-defined localities progressed to a peak 2 months post-inoculation, followed by some degree of normalization. However, bone thickness was still massively increased 6 months after the acute incident. Except in the otic capsule, resorptive and formative activity was found in all bone tissue structures surrounding the middle ear cavity. These findings were irrespective of the type of inoculated bacteria. However, non-typeable or type b Haemophilus influenzae induces significantly more new bone formation than Moraxella catarrhalis. We conclude that acute otitis media caused by either of the bacteria is accompanied by massive and progressive net osteoneogenesis, already evident on day 4 and peaking 2 months post-inoculation, followed by some degree of normalization. Non-typeable and type b Haemophilus influenzae induce more new bone formation than Moraxella catarrhalis, whereas other features of bone histomorphology were equivalent. The present findings further support the existence of a perilymphatic zone of specialized bone.

Acute Disease↗
PubMed2000

Structure and sequence analysis of Yersinia YadA and Moraxella UspAs reveal a novel class of adhesins.

The non-fimbrial adhesins, YadA of enteropathogenic Yersinia species, and UspA1 and UspA2 of Moraxella catarrhalis, are established pathogenicity factors. In electron micrographs, both surface proteins appear as distinct 'lollipop'-shaped structures forming a novel type of surface projection on the outer membranes. These structures, amino acid sequence analysis of these molecules and yadA gene manipulation suggest a tripartite organization: an N-terminal oval head domain is followed by a putative coiled-coil rod and terminated by a C-terminal membrane anchor domain. In YadA, the head domain is involved in autoagglutination and binding to host cells and collagen. Analysis of the coiled-coil segment of YadA revealed unusual pentadecad repeats with a periodicity of 3.75, which differs significantly from the 3.5 periodicity found in the Moraxella UspAs and other canonical coiled coils. These findings predict that the surface projections are formed by oligomers containing right- (Yersinia) or left-handed (Moraxella) coiled coils. Strikingly, sequence comparison revealed that related proteins are found in many proteobacteria, both human pathogenic and environmental species, suggesting a common role in adaptation to specific ecological niches.

Adhesins, Bacterial↗
PubMed1979

Endocarditis caused by Moraxella nonliquefaciens.

We have described a case of endocarditis caused by Moraxella nonliquefaciens on a prosthetic Hancock valve, which was cured with a six-week course of ampicillin and gentamicin therapy. Cases of Moraxella septicemia or endocarditis are uncommon, and this apparently represents the first case of Moraxella nonliquefaciens endocarditis on a prosthetic valve. The fastidious growth characteristics of this and similar species may require prolonged incubation of blood cultures and development of different methods for testing the bactericidal activity of the patient's serum.

Ampicillin↗
PubMed1980

Thermal inactivation and injury of Moraxella-Acinetobacter cells in ground beef.

The thermal inactivation and injury (sensitivity to 0.8% NaCl) of a radiation-resistant culture of Moraxella-Acinetobacter mixed in minced beef were determined. Survival curves for Moraxella-Acinetobacter cells in beef had an initial shoulder preceding a logarithmic decline when the cells were heated at 65, 70, and 75 degrees C, but not at 80 degrees C. In all cases, the experimental points not included in the shoulder were linearized by means of a least-squares straight line, and the latter was used to determine D values. Shoulder values of 12.2, 4.1, and 0.6 min at temperatures of 65, 70, and 75 degrees C were added to the respective D values of 35.4, 6.6, and 1.4 min to determine the time required to destroy one log cycle. The Z value was 7.3 degrees C. Moraxella-Acinetobacter cells in meat were more rapidly injured than inactivated, on initial exposure to heat. The number of cells injured by this initial exposure increased as the temperature was increased. At 65 degrees C the percentage of injured cells increased more rapidly with exposure time than did the inactivated cells. As the temperature was increased, the rates of inactivation and injury became more and more similar.

Acinetobacter↗
PubMed1974

Characterization and differentiation of 59 strains of Moraxella urethralis from clinical specimens.

The biochemical characteristics of 59 strains of Moraxella urethralis from clinical specimens, primarily from urine and the female genital tract, were studied. The characteristics included (i) the inability to acidify carbohydrate substrates, (ii) the ability to produce phenylalanine deaminase, (iii) the ability to reduce nitrite, (iv) the lack of urease activity, and (v) the ability of most strains to alkalinize citrate. A means of differentiating M. urethralis from Moraxella osloensis and Moraxella phenylpyruvica was determined.

Aminohydrolases↗
PubMed1970

Nucleic acid homologies among oxidase-negative Moraxella species.

The deoxyribonucleic acid (DNA) base composition and DNA homologies of more than 40 strains of oxidase-negative Moraxella species were determined. These bacteria have also been identified as belonging to the Mima-Herellea-Acinetobacter group and the Bacterium anitratum group, as well as to several other genera including Achromobacter and Alcaligenes. The DNA base content of these strains ranged from 40 to 46% guanine plus cytosine. DNA-DNA competition experiments distinguished five groups whose members were determined by showing 50% or more homology to one of the reference strains: B. anitratum type B5W, Achromobacter haemolyticus var. haemolyticus, Alcaligenes haemolysans, Achromobacter metalcaligenes, and Moraxella lwoffi. A sixth group comprised those strains showing less than 50% homology to any of the reference strains. Negligible homology was found between strains of oxidase-negative and oxidase-positive Moraxella species in DNA-DNA competition experiments. However, evidence of a distant relationship between the two groups was obtained in competition experiments by using ribosomal ribonucleic acid.

Bacteria↗
PubMed1987

Combined genetic transformation and nutritional assay for identification of Moraxella nonliquefaciens.

A combined genetic transformation and nutritional assay is described that permits definitive identification of clinically isolated strains of Moraxella nonliquefaciens. Crude DNA preparations of strains of various Moraxella species were used to transform nutritional mutants of a stably competent strain of M. nonliquefaciens for ability to grow on a defined medium (Mn-B). DNA samples from 24 independently isolated strains of M. nonliquefaciens all resulted in massive (4+) transformation of each of two mutant assay strains. DNA samples from strains of M. bovis and M. lacunata frequently gave weak (1+) transformation of one of the mutant assay strains (Mn64) but almost always failed to transform another assay strain (Mn136). DNA samples from eight other Moraxella species failed completely to transform either of the mutant assay strains. When streaked on the defined medium used for the transformation assay (Mn-B), 23 of the 24 strains of M. nonliquefaciens grew well, but all strains of M. bovis and M. lacunata failed to grow on this medium.

Culture Media↗
PubMed2000

Moraxella catarrhalis pneumonia during HIV disease.

To assess the role of Moraxella catarrhalis complications in the setting of HIV disease, and to evaluate their occurrence and outcome according to several epidemiological, clinical, and laboratory parameters, the clinical records of 2123 consecutive HIV-infected patients hospitalized in a 9-year period were retrospectively reviewed, and 4 cases of community-acquired M. catarrhalis pneumonia were identified. Three adult patients had a diagnosis of AIDS and severe concurrent immunodeficiency (with a CD4+ lymphocyte count below 60 cells/microL), while the fourth case involved a child with vertical HIV disease. Leukopenia and neutropenia were never present, but no patient received a potent antiretroviral regimen at the time of disease onset. A concurrent respiratory infection by Streptococcus pneumoniae and Mycobacterium tuberculosis was recognized in 2 of 4 patients. Isolated M. catarrhalis strains were susceptible to all tested antimicrobial compounds (save ampicillin in 2 cases), and appropriate antimicrobial treatment led to clinical and microbiological cure in all described episodes. Only 8 cases of HIV-associated Moraxella spp. disease have been reported to date in seven different literature reports (6 cases of pneumonia, and 1 of septicemia). According to our experience, M. catarrhalis may be responsible for appreciable morbidity among patients with advanced HIV infection, especially when a low CD4+ cell count or coexisting respiratory disease are present. Clinicians and microbiologists who care for HIV-infected patients should carefully consider the potential pathogenic role of Moraxella spp. organisms.

AIDS-Related Opportunistic Infections↗
PubMed2002

Identification of an antifreeze lipoprotein from Moraxella sp. of Antarctic origin.

We found six bacteria capable of producing antifreeze protein (AFP) from Ross Island, Antarctica. Among these AFP-producing bacteria, strain No. 82 had the highest antifreeze activity and was identified as Moraxella sp. The optimum temperature and pH for the production of AFP were 5 degrees C and 7.0, respectively. After partially purifying the AFP from the culture supernatant using 60% saturation of ammonium sulfate, only the 52-kDa protein band (100 microg/ml) which eluted from SDS-PAGE indicated antifreeze activity by the formation of hexagonal crystals. Furthermore, we confirmed that this AFP was a lipoprotein by the lipid stain test and treatment with some enzymes and that it had no ice-nucleating activity. Also, the N-terminal amino acid sequence of this AFP had high similarity with that of outer membrane proteins from Moraxella (Branhamella) catarrhalis. This is the first report of AFP-producing bacteria in Antarctica and an antifreeze lipoprotein (AFLP) from Moraxella sp.

Amino Acid Sequence↗
PubMed2000

Detection of cell detachment activity induced by Moraxella bovis.

OBJECTIVE: To characterize the effect that filtrate obtained from cultures of Moraxella bovis has on cultured corneal epithelial cells and other types of cultured mammalian cells. SAMPLE POPULATION: Cultured hamster corneal epithelial cells, bovine epithelial cells, and several transformed cell lines exposed to culture filtrate from a pathogenic isolate of M bovis. PROCEDURE: Moraxella bovis was cultured, and bacteria were removed by filtration. The resulting bacterial culture filtrate was incubated with various types of cultured cells, and effects of the filtrate on detachment of various mammalian cell types was quantified by the use of neutral red dye. Additionally, bacterial culture filtrate was treated with protease inhibitors as well as trypsin and heat prior to incubation with cultured mammalian cells. RESULTS: Bacterial culture filtrate of M bovis caused all types of cultured cells to detach from each other and from the substrate, with the maximal effect evident 2 hours after initiating incubation. Detached cells were alive, and detachment was reversible. Serine protease inhibitors (phenylmethylsulfonylfluoride and alpha2-macroglobulin) inhibited cell detachment attributable to bacterial culture filtrate. Heating and treatment with trypsin also inhibited cell detachment. CONCLUSIONS AND CLINICAL RELEVANCE: Moraxella bovis produces a soluble factor that causes reversible detachment of cultured cells. This activity may play a role in the pathogenesis of infectious bovine keratoconjunctivitis.

Animals↗
PubMed2005

Ionic binding of C3 to the human pathogen Moraxella catarrhalis is a unique mechanism for combating innate immunity.

Moraxella catarrhalis ubiquitous surface proteins A1 and A2 (UspA1/A2) interfere with the classical pathway of the complement system by binding C4b-binding protein. In this study we demonstrate that M. catarrhalis UspA1 and A2 noncovalently and in a dose-dependent manner bind both the third component of complement (C3) from EDTA-treated serum and methylamine-treated C3. In contrast, related Moraxella subspecies (n = 13) or other human pathogenic bacteria (n = 13) do not bind C3 or methylamine-treated C3. Experiments with recombinant proteins and M. catarrhalis mutants devoid of UspA1/A2 revealed that UspA1/A2 exert their actions by absorbing and neutralizing C3 from serum and restrain complement activation. UspA2 was responsible for most of the effect, and the Moraxella mutant lacking UspA2 was more sensitive to the lytic effect of human serum compared with the wild type. Interestingly, among the large number of bacteria analyzed, only M. catarrhalis has this unique ability to interfere with the innate immune system of complement by binding C3.

Bacterial Outer Membrane Proteins↗
PubMed1998

Bronchopulmonary infection due to Moraxella (Branhamella) catarrhalis at a specialist hospital in Saudi Arabia.

Moraxella (Branhamella) catarrhalis is now considered as one of the most important causative organisms responsible for respiratory tract infection. Specimens of tracheal aspirates from inpatients at King Fahd specialist hospital, Buraidah, Saudi Arabia were collected over a period of 18 months to determine prospectively the frequency of Moraxella catarrhalis and its antimicrobial susceptibility. Moraxella catarrhalis was isolated in pure culture from 3.8% of the tracheal aspirates collected from patients with symptoms of acute respiratory tract infections. It was the third most important pathogen after Haemophilus influenzae and Streptococcus pneumoniae; 76% of the patients had an underlying chronic obstructive pulmonary disease (COPD). The significance of the findings is discussed.

Adolescent↗
PubMed1975

The problem of pathogenicity of Moraxellae in the urogenital tract of women.

The incidence of Moraxella nonliquefaciens an M. liquefaciens in the urogenital tract is relatively low. These microorganisms were detected in 0.77% of cases during the examination of a total of 3 761 women. M. nonliquefaciens was found in 26 out of 29 cases. The frequency of occurrence did not differ in the groups of healthy women, of women with inflammatory signs in the urogenital tract and of women with confirmed gonorrhoea. We therefore believe that these moraxellae do not play any pathogenetic role in this localization. In our opinion, the similarity of microscopic preparations and the shape of the colonies of these moraxellae with those of Neisseria gonorrhoeae is noteworthy: unless glucose splitting test is carried out, the two species can frequently be confused. The test of sensitivity to antibiotics revealed a considerable decrease in sensitivity to penicillin G as compared with the report of Bövre and Henricksen (1967). Sensitivity to other antibiotics remained unchanged.

Anti-Bacterial Agents↗