| a membrane-bound precursor beta-lactamase in strains of moraxella catarrhalis and moraxella nonliquefaciens that produce periplasmic bro-1 and bro-2 beta-lactamases. | by employing the non-ionic detergent triton x-100, a membrane-bound beta-lactamase was extracted from strains of moraxella (branhamella) catarrhalis and moraxella nonliquefaciens that produce bro-1 and bro-2 beta-lactamases. unlike bro-1 and bro-2, which exhibit multiple major bands on isoelectric focusing (ief), the membrane-bound enzyme focused as a single ief band at a pi of 6.20, which was not present with either of the other two enzymes. the membrane-bound beta-lactamase could be extracted ... | 1993 | 8463169 |
| characterization of the kingella kingae polysaccharide capsule and exopolysaccharide. | recent evidence indicates that kingella kingae produces a polysaccharide capsule. in an effort to determine the composition and structure of this polysaccharide capsule, in the current study we purified capsular material from the surface of k. kingae strain 269-492 variant kk01 using acidic conditions to release the capsule and a series of steps to remove dna, rna, and protein. analysis of the resulting material by gas chromatography and mass spectrometry revealed n-acetyl galactosamine (galnac) ... | 2013 | 24098695 |
| evaluation of the bruker maldi biotyper for identification of fastidious gram-negative rods. | matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof ms) has entered clinical laboratories, facilitating identification of bacteria. here, we evaluated the maldi biotyper (bruker daltonics) for the identification of fastidious gram-negative rods (gnr). three sample preparation methods, direct colony transfer, direct transfer plus on-target formic acid preparation, and ethanol-formic acid extraction, were analyzed for 151 clinical isolates. direct colony transfe ... | 2016 | 26659214 |
| evaluation of the genbank, eztaxon, and bibi services for molecular identification of clinical blood culture isolates that were unidentifiable or misidentified by conventional methods. | we compared the 16s rrna gene sequencing results analyzed with the genbank, eztaxon, and bibi databases for blood culture specimens for which identifications were incomplete, conflicting, or unidentifiable using conventional methods. analyses performed using genbank combined with eztaxon (kappa = 0.79) were more discriminative than those using other databases alone or in combination with a second database. | 2012 | 22403421 |
| separate pathways for o acetylation of polymeric and monomeric sialic acids and identification of sialyl o-acetyl esterase in escherichia coli k1. | o acetylation at carbon positions 7 or 9 of the sialic acid residues in the polysialic acid capsule of escherichia coli k1 is catalyzed by a phase-variable contingency locus, neuo, carried by the k1-specific prophage, cus-3. here we describe a novel method for analyzing polymeric sialic acid o acetylation that involves the release of surface sialic acids by endo-n-acetylneuraminidase digestion, followed by fluorescent labeling and detection of quinoxalinone derivatives by chromatography. the res ... | 2006 | 16923886 |
| recurrent gram-negative bloodstream infection: a 10-year population-based cohort study. | recurrent gram-negative bloodstream infection (bsi) has not been evaluated in a population-based setting; therefore, we performed a population-based retrospective cohort study to examine the incidence, recurrence, and mortality rates of gram-negative bsi. | 2010 | 20378069 |
| integrated analysis of three bacterial conjunctivitis trials of besifloxacin ophthalmic suspension, 0.6%: etiology of bacterial conjunctivitis and antibacterial susceptibility profile. | the purpose of this paper is to report on the bacterial species isolated from patients with bacterial conjunctivitis participating in three clinical trials of besifloxacin ophthalmic suspension, 0.6%, and their in vitro antibacterial susceptibility profiles. | 2011 | 22034556 |
| masquerading microbial pathogens: capsular polysaccharides mimic host-tissue molecules. | the increasing prevalence of antibiotic-resistant bacteria portends an impending postantibiotic age, characterized by diminishing efficacy of common antibiotics and routine application of multifaceted, complementary therapeutic approaches to treat bacterial infections, particularly multidrug-resistant organisms. the first line of defense for most bacterial pathogens consists of a physical and immunologic barrier known as the capsule, commonly composed of a viscous layer of carbohydrates that are ... | 2014 | 24372337 |
| spectrum and sensitivity of bacterial keratitis isolates in auckland. | background. the bacteria isolated from severe cases of keratitis and their antibiotic sensitivity are recognised to vary geographically and over time. objectives. to identify the most commonly isolated bacteria in keratitis cases admitted over a 24-month period to a public hospital in auckland, new zealand, and to investigate in vitro sensitivity to antibiotics. methods. hospital admissions for culture-proven bacterial keratitis between january 2013 and december 2014 were identified. laboratory ... | 2016 | 27213052 |
| procalcitonin levels in gram-positive, gram-negative, and fungal bloodstream infections. | procalcitonin (pct) can discriminate bacterial from viral systemic infections and true bacteremia from contaminated blood cultures. the aim of this study was to evaluate pct diagnostic accuracy in discriminating gram-positive, gram-negative, and fungal bloodstream infections. a total of 1,949 samples from patients with suspected bloodstream infections were included in the study. median pct value in gram-negative (13.8 ng/ml, interquartile range (iqr) 3.4-44.1) bacteremias was significantly highe ... | 2015 | 25852221 |
| analysis of the sds-page patterns of outer membrane proteins from escherichia coli strains that have lost the ability to form k1 antigen and varied in the susceptibility to normal human serum. | we used sds-polyacrylamide gel electrophoresis to investigate the outer membrane proteins (omps) band composition of 19 escherichia coli k1 strains that have spontaneously lost the ability to form k1 polysaccharide capsule (e. coli k1-) and demonstrated different degrees of susceptibility to the bactericidal action of normal human serum. presented results showed that there were differences between e. coli k1- strains in omps expressing capacity. the analysis performed on omps has not revealed a ... | 2013 | 23794053 |
| analysis of the sds-page patterns of outer membrane proteins from escherichia coli strains that have lost the ability to form k1 antigen and varied in the susceptibility to normal human serum. | we used sds-polyacrylamide gel electrophoresis to investigate the outer membrane proteins (omps) band composition of 19 escherichia coli k1 strains that have spontaneously lost the ability to form k1 polysaccharide capsule (e. coli k1-) and demonstrated different degrees of susceptibility to the bactericidal action of normal human serum. presented results showed that there were differences between e. coli k1- strains in omps expressing capacity. the analysis performed on omps has not revealed a ... | 2013 | 23794053 |
| performance comparison of illumina and ion torrent next-generation sequencing platforms for 16s rrna-based bacterial community profiling. | high-throughput sequencing of the taxonomically informative 16s rrna gene provides a powerful approach for exploring microbial diversity. here we compare the performances of two common "benchtop" sequencing platforms, illumina miseq and ion torrent personal genome machine (pgm), for bacterial community profiling by 16s rrna (v1-v2) amplicon sequencing. we benchmarked performance by using a 20-organism mock bacterial community and a collection of primary human specimens. we observed comparatively ... | 2014 | 25261520 |
| profiling bacterial community in upper respiratory tracts. | infection by pathogenic viruses results in rapid epithelial damage and significantly impacts on the condition of the upper respiratory tract, thus the effects of viral infection may induce changes in microbiota. thus, we aimed to define the healthy microbiota and the viral pathogen-affected microbiota in the upper respiratory tract. in addition, any association between the type of viral agent and the resultant microbiota profile was assessed. | 2014 | 25391813 |
| evidence that intraspecific trait variation among nasal bacteria shapes the distribution of staphylococcus aureus. | nasal carriage of staphylococcus aureus is a risk factor for infection, yet the bacterial determinants required for carriage are poorly defined. interactions between s. aureus and other members of the bacterial flora may determine colonization and have been inferred in previous studies by using correlated species distributions. however, traits mediating species interactions are often polymorphic, suggesting that understanding how interactions structure communities requires a trait-based approach ... | 2014 | 24980973 |
| detection of k1 antigen of escherichia coli rods isolated from pregnant women and neonates. | the k1 antigen is an important virulence determinant of escherichia coli strains and has been shown to be associated particularly with neonatal meningitis, bacteraemia and septicaemia. thus, its detection seems to be useful, especially in the case of e. coli strains isolated from pregnant women and newborns. in this study, the sensitivity and specificity of the latex agglutination test (pastorex meningitis) for identification of e. coli serogroup k1 were assessed, using pcr as the gold standard. ... | 2014 | 24737297 |
| effects of vaccination with 10-valent pneumococcal non-typeable haemophilus influenza protein d conjugate vaccine (phid-cv) on the nasopharyngeal microbiome of kenyan toddlers. | pneumococcal conjugate vaccines reduce the prevalence of vaccine serotypes carried in the nasopharynx. because this could alter carriage of other potential pathogens, we assessed the nasopharyngeal microbiome of children who had been vaccinated with 10-valent pneumococcal non-typeable haemophilus influenzae protein-d conjugate vaccine (phid-cv). | 2015 | 26083474 |
| kingella kingae expresses four structurally distinct polysaccharide capsules that differ in their correlation with invasive disease. | kingella kingae is an encapsulated gram-negative organism that is a common cause of osteoarticular infections in young children. in earlier work, we identified a glycosyltransferase gene called csaa that is necessary for synthesis of the [3)-β-galpnac-(1→5)-β-kdop-(2→] polysaccharide capsule (type a) in k. kingae strain 269-492. in the current study, we analyzed a large collection of invasive and carrier isolates from israel and found that csaa was present in only 47% of the isolates. further ex ... | 2016 | 27760194 |
| the microbiota in bronchoalveolar lavage from young children with chronic lung disease includes taxa present in both the oropharynx and nasopharynx. | invasive methods requiring general anaesthesia are needed to sample the lung microbiota in young children who do not expectorate. this poses substantial challenges to longitudinal study of paediatric airway microbiota. non-invasive upper airway sampling is an alternative method for monitoring airway microbiota; however, there are limited data describing the relationship of such results with lung microbiota in young children. in this study, we compared the upper and lower airway microbiota in you ... | 2016 | 27388563 |
| nasopharyngeal microbiota composition of children is related to the frequency of upper respiratory infection and acute sinusitis. | upper respiratory infections (uri) and their complications are a major healthcare burden for pediatric populations. although the microbiology of the nasopharynx is an important determinant of the complications of uri, little is known of the nasopharyngeal (np) microbiota of children, the factors that affect its composition, and its precise relationship with uri. | 2016 | 27364497 |
| meningitis due to moraxella nonliquefaciens in a paediatric patient: a case report and review of the literature. | introduction.moraxella nonliquefaciens is an unusual organism to be isolated from cerebral spinal fluid (csf) and there exists only one case report of m. nonliquefaciens meningitis from a neonate. moraxella species normally exist as part of the human upper respiratory tract flora and rarely cause invasive human disease. there are only a handful of case reports implicating the organism as a cause of endocarditis, bacteraemia, septic arthritis and endophthalmitis. identification to the species lev ... | 2017 | 28348808 |
| a fatal endocarditis case due to an emerging bacterium: moraxella nonliquefaciens. | moraxella nonliquefaciens is a gram-negative coccobacillus considered as a commensal organism from the upper respiratory tract, with low pathogenic potential. the phenotypical conventional identification is difficult and the matrix-assisted laser desorption/ionization time-of-flight technology has increased the resolution of identification of this bacterium. we report a fatal case of endocarditis due to m. nonliquefaciens whose identification was confirmed by 16s rrna, and we review the literatu ... | 2017 | 28271043 |
| antimicrobial susceptibility and mechanisms of high-level macrolide resistance in clinical isolates of moraxella nonliquefaciens. | we investigated antimicrobial susceptibility and the molecular mechanism involved in conferring high-level macrolide resistance in 47 clinical isolates of moraxella nonliquefaciens from japan. antimicrobial susceptibility was determined using etest and agar dilution methods. thirty-two erythromycin-non-susceptible strains were evaluated for the possibility of clonal spreading, using pfge. to analyse the mechanism related to macrolide resistance, mutations in the 23s rrna gene and the ribosomal p ... | 2014 | 24196134 |
| assessing genetic structure, diversity of bacterial aerosol from aeration system in an oxidation ditch wastewater treatment plant by culture methods and bio-molecular tools. | airborne bacteria emissions from oxidation ditch with rotating aeration brushes were investigated in a municipal wastewater treatment plant in beijing, china. microbial samples were collected at different distances from the rotating brushes, different heights above the water surface, and different operation state over a 3-month period (april, may, and june) in order to estimate the seasonal variation and site-related distribution characteristics of the microorganisms present. the concentration o ... | 2013 | 22402990 |