-
Journal of Bacteriology Mar 1975Gentisate:oxygen 1,2-oxidoreductase (decyclizing) (EC 1.13.11.4; gentisate 1,2-dioxygenase) from Moraxella osloensis was purified to homogeneity as shown by...
Gentisate:oxygen 1,2-oxidoreductase (decyclizing) (EC 1.13.11.4; gentisate 1,2-dioxygenase) from Moraxella osloensis was purified to homogeneity as shown by polyacrylamide gel electrophoresis. The enzyme has a molecular weight of about 154,000 and gives rise to subunits of molecular weight 40,000 in the presence of sodium dodecyl sulfate. Gentisate 1,2-dioxygenase showed broad substrate specificity and attacked a range of halogen- and alkyl-substituted gentisic acids. Maleylpyruvate, the product formed from gentisate, was degraded by cell extracts supplemented with reduced glutathione, but substituted maleylpyruvates were not attacked under these conditions.
Topics: Ammonium Sulfate; Cell Fractionation; Cell-Free System; Chemical Phenomena; Chemical Precipitation; Chemistry; Chromatography, DEAE-Cellulose; Chromatography, Gel; Electrophoresis, Polyacrylamide Gel; Gentisates; Glutathione; Hot Temperature; Hydrogen-Ion Concentration; Isomerases; Kinetics; Molecular Weight; Moraxella; Oxygenases; Pyruvates; Salicylates; Soil Microbiology; Spectrophotometry, Ultraviolet
PubMed: 234947
DOI: 10.1128/jb.121.3.794-799.1975 -
Journal of Infection Prevention Nov 2020Protective lead garments (PLG) worn in the operating room are a potential source for bacterial colonisation and thus may increase the risk of intraoperative infection....
BACKGROUND
Protective lead garments (PLG) worn in the operating room are a potential source for bacterial colonisation and thus may increase the risk of intraoperative infection. The clinical significance of such bacterial contamination has yet been established. Although disinfection protocols have been employed, their effectiveness is also unknown.
OBJECTIVE
We sought to describe and compare the bacterial profile of PLGs with a focus on common pathogens involved in surgical site infections (SSI) and prosthetic joint infections (PJI).
METHODS
We studied body aprons and neck-thyroid protective shields. We sampled 20 body aprons and 21 neck PLGs, swabbing the inside and outside of the PLGs. Swabs were cultured on different media and the results were assessed and compared.
RESULTS
Of PLGs, 87.8% were contaminated. The neck-thyroid shield PLGs was generally more contaminated than body apron PLGs and exhibited significantly higher loads of ( = 0.048). Other pathogen cultured were spp., (), species ( spp.), () and (). No other common pathogens associated with SSI or PJI were detected.
CONCLUSIONS
PLGs are heavily contaminated despite regular cleaning protocols. Neck PLGs are highly contaminated with potentially infectious agents. As neck PLGs are often directly exposed above the surgical sterile gown and the surgical field, measures should be undertaken to reduce their exposure and bacterial load, perhaps by suggesting users consider avoiding the use of intraoperative fluoroscopy when possible or alternatively supporting the use of body exhaust suits when PLGs are needed.
PubMed: 33408761
DOI: 10.1177/1757177420947466 -
PLoS Genetics May 2018Polymyxin is the last line of defense against severe infections caused by carbapenem-resistant gram-negative pathogens. The emergence of transferable MCR-1/2 polymyxin...
Polymyxin is the last line of defense against severe infections caused by carbapenem-resistant gram-negative pathogens. The emergence of transferable MCR-1/2 polymyxin resistance greatly challenges the renewed interest in colistin (polymyxin E) for clinical treatments. Recent studies have suggested that Moraxella species are a putative reservoir for MCR-1/2 genetic determinants. Here, we report the functional definition of ICR-Mo from M. osloensis, a chromosomally encoded determinant of colistin resistance, in close relation to current MCR-1/2 family. ICR-Mo transmembrane protein was prepared and purified to homogeneity. Taken along with an in vitro enzymatic detection, MALDI-TOF mass spectrometry of bacterial lipid A pools determined that the ICR-Mo enzyme might exploit a possible "ping-pong" mechanism to accept the phosphoethanolamine (PEA) moiety from its donor phosphatidylethanolamine (PE) and then transfer it to the 1(or 4')-phosphate position of lipid A via an ICR-Mo-bound PEA adduct. Structural decoration of LPS-lipid A by ICR-Mo renders the recipient strain of E. coli resistant to polymyxin. Domain swapping assays indicate that the two domains of ICR-Mo cannot be functionally-exchanged with its counterparts in MCR-1/2 and EptA, validating its phylogenetic position in a distinct set of MCR-like genes. Structure-guided functional mapping of ICR-Mo reveals a PE lipid substrate recognizing cavity having a role in enzymatic catalysis and the resultant conference of antibiotic resistance. Expression of icr-Mo in E. coli significantly prevents the formation of reactive oxygen species (ROS) induced by colistin. Taken together, our results define a member of a group of intrinsic colistin resistance genes phylogenetically close to the MCR-1/2 family, highlighting the evolution of transferable colistin resistance.
Topics: Anti-Bacterial Agents; Bacterial Proteins; Colistin; Drug Resistance, Bacterial; Ethanolamines; Membrane Proteins; Molecular Docking Simulation; Moraxella; Phosphatidylethanolamines; Phylogeny; Protein Binding; Substrate Specificity
PubMed: 29758020
DOI: 10.1371/journal.pgen.1007389 -
Genome Announcements Jan 2018Here, we present the complete whole-genome sequences of three strains with octylphenol polyethoxylate-degrading abilities. These strains were isolated from human skin.
Here, we present the complete whole-genome sequences of three strains with octylphenol polyethoxylate-degrading abilities. These strains were isolated from human skin.
PubMed: 29348360
DOI: 10.1128/genomeA.01509-17 -
Environmental Research Feb 2023With the growing numbers of the urban population, an increasing number of commuters have relied on subway systems for rapid transportation in daily life. Analyzing the...
With the growing numbers of the urban population, an increasing number of commuters have relied on subway systems for rapid transportation in daily life. Analyzing the temporal distribution of air microbiomes in subway environments is crucial for the assessment and monitoring of air quality in the subway system, especially with regard to public health. This study employed culture-independent metabarcode sequencing to analyze bacterial diversity and variations in bacterial compositions associated with bioaerosols collected from a subway station in Bangkok over a four-month period. The bacteria obtained were found to consist primarily of Proteobacteria, Firmicutes, and Actinobacteria, with variations at the family, genus, and species levels among samples obtained in different months. The vast majority of these bacteria are most likely derived from outside environments and human body sources. Many of the bacteria found in Bangkok subway station were also identified as "core microorganisms" of subway environments around the world, as suggested by the MetaSUB Consortium. The diversity of bacterial communities was shown to be influenced by several air quality variables, especially ambient temperature and the quantity of particulate matters, which showed positive correlations with several bacterial species such as Acinetobacter lwoffii, Staphylococcus spp., and Moraxella osloensis. In addition, metabolic profiles inferred from metabarcode-derived bacterial diversity showed significant variations across different sampling times and sites and can be used as a starting point to further explore the functional roles of specific groups of bacteria in the subway environment. This study thus introduced the information required for surveillance of microbiological impacts and their contributions to the well-being of subway commuters in Bangkok.
Topics: Humans; Railroads; Thailand; Microbiota; Air Pollution; Transportation; Particulate Matter; Bacteria; Air Pollutants; Environmental Monitoring
PubMed: 36535389
DOI: 10.1016/j.envres.2022.115065 -
Journal of Bacteriology Jan 1968A number of strains of oxidase-positive moraxellas and of neisserias related to Neisseria catarrhalis were characterized with respect to a number of nutritional and...
A number of strains of oxidase-positive moraxellas and of neisserias related to Neisseria catarrhalis were characterized with respect to a number of nutritional and physiological properties and could be assigned to several species or species groups on the basis of their phenotypic traits. This grouping was consistent with that established by Bövre on the basis of transformation frequencies for streptomycin resistance. It is proposed to reserve the generic name Moraxella for the oxidase-positive rodshaped organisms, and a redescription of the genus is offered. Following the recent taxonomic proposals of Bövre and Henriksen, the specific name Moraxella osloensis is applied to the nutritionally unexacting strains that accumulate poly-beta-hydroxybutyrate as carbon reserve. The nutritionally exacting strains are assigned to three distinct groups which can be regarded as separate species or as varieties of M. lacunata. The epithets applicable to these groups appear to be lacunata, nonliquefaciens, and bovis. The "false neisserias" could be assigned to at least three subgroups, one of which constitutes the clearly defined entity, N. catarrhalis, which could be distinguished from N. caviae and N. ovis.
Topics: Microscopy, Phase-Contrast; Moraxella; Neisseria
PubMed: 4866103
DOI: 10.1128/jb.95.1.58-73.1968 -
Applied Microbiology Jan 1974A genetic transformation assay for unequivocal identification of strains of Moraxella osloensis is described. In this assay a stable tryptophan auxotroph is transformed...
A genetic transformation assay for unequivocal identification of strains of Moraxella osloensis is described. In this assay a stable tryptophan auxotroph is transformed to prototrophy by deoxyribonucleic acid (DNA) samples from other strains of M. osloensis but not by DNA samples from unrelated bacteria. The test is simple to perform and definitive results can be obtained in less than 24 h. The procedure, which is suitable for routine diagnosis in a clinical laboratory, involves a rapid method for preparation of crude transforming DNA from small quantities of bacterial cells and permits simultaneous examination of large numbers of isolated cultures. The assay was shown to correctly identify 27 strains previously classified as M. osloensis. Forty-five other gram-negative, oxidase-positive, nonmotile coccobacilli, which might be confused with M. osloensis unless subject to more extensive testing, were shown to be unrelated genetically to M. osloensis. The transformation assay clearly distinguishes M. osloensis from Acinetobacter. Although most strains of M. osloensis are nonfastidious, being able to grow in a mineral medium supplemented with a single organic carbon source, one of the strains tested was only able to grow on fairly complex media and could not be transformed to grow on simple media. Inability to alkalize Simmons citrate agar was shown not to be characteristic of all strains of M. osloensis.
Topics: Acinetobacter; Alcaligenes; Bacteriological Techniques; Culture Media; DNA, Bacterial; Methods; Micrococcus; Moraxella; Mutagens; Mutation; Nitrosoguanidines; Transformation, Genetic; Tryptophan
PubMed: 4589126
DOI: 10.1128/am.27.1.16-24.1974 -
Journal of Clinical Microbiology Jun 1982Moraxella osloensis osteomyelitis of the femur developed in a paraplegic man. He responded to treatment with oral ampicillin. Disease in humans caused by this unusual...
Moraxella osloensis osteomyelitis of the femur developed in a paraplegic man. He responded to treatment with oral ampicillin. Disease in humans caused by this unusual clinical isolate is reviewed.
Topics: Adult; Ampicillin; Bacterial Infections; Femur; Humans; Male; Moraxella; Osteomyelitis
PubMed: 7107844
DOI: 10.1128/jcm.15.6.1148-1149.1982 -
Journal of Veterinary Research Sep 2023Universally, in microbiological diagnostics the detection of live bacteria is essential. Rapid identification of pathogens enables appropriate remedial measures to be...
INTRODUCTION
Universally, in microbiological diagnostics the detection of live bacteria is essential. Rapid identification of pathogens enables appropriate remedial measures to be taken. The identification of many bacteria simultaneously facilitates the determination of the characteristics of the accompanying microbiota and/or the microbiological complexity of a given environment.
MATERIAL AND METHODS
The effectiveness of the VITEK2 Compact automated microbial identification system and matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS), analytical profile index (API) and Remel RapID tests were compared in identification of bacteria isolated from the alpaca gastrointestinal tract.
RESULTS
Most isolates were Gram-positive, such as and and , , and ; ; ; ; ; , , and (the last only isolated manually by API Coryne and the VITEK2 system and (CBC) card). was misidentified by MALDI-TOF MS as (currently ). Gram-positive and Gram-variable were also isolated. Gram-negative , , and ; ; subsp. ; and ; , and ; subsp. ; ; ; ; ; and were also found. The yeasts and were also present.
CONCLUSION
MALDI-TOF MS enabled the identification of pathogens and opportunistic pathogens from the alpaca gut which may represent a high risk to human and animal health.
PubMed: 37786852
DOI: 10.2478/jvetres-2023-0051 -
International Journal of General... 2012Moraxella osloensis is a rare causative organism of infections in humans, with most cases reported in cancer patients. We report the case of a 67-year-old Japanese man...
Moraxella osloensis is a rare causative organism of infections in humans, with most cases reported in cancer patients. We report the case of a 67-year-old Japanese man with advanced cancer of the pancreatic head and multiple liver metastases who developed fever with chills. Blood culture was found to be positive for Gram-negative bacilli that were aerobic, oxidase-positive, and catalase-positive. M. osloensis was identified by 16 rRNA gene sequencing. Prompt control of the infection was achieved by treatment with cefepime for 14 days, without the need for removal of the central venous catheter.
PubMed: 23109812
DOI: 10.2147/IJGM.S36919