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Respirology Case Reports Aug 2018The exact incidence of foreign body aspiration among adults is unknown, and its clinical presentation is vastly divergent. We report the previously undescribed...
The exact incidence of foreign body aspiration among adults is unknown, and its clinical presentation is vastly divergent. We report the previously undescribed occurrence of cockroach aspiration in an adult, presenting with a "crawling sensation" in his chest. Flexible endobronchial examination revealed a foreign body impacted in the lingula, resembling the Australian cockroach Periplaneta australasiae. Partial extraction via biopsy forceps was performed and complicated by acute hypoxia on disimpaction, requiring a brief period of bag/mask ventilation. Following the offset of procedural sedation, the remaining foreign body was manually expectorated. A total of 24 h post-procedure, the patient was febrile with positive blood cultures (Micrococcus luteus). We highlight the importance of definitive airway support during endobronchial interventions and raise the question regarding the significance of transient bacteraemia following bronchoscopic manipulation.
PubMed: 29850021
DOI: 10.1002/rcr2.332 -
Macromolecular Bioscience Nov 2021Bioremediation of copper (Cu ) with immobilized Micrococcus luteus in polymer matrices has been broadly studied for a wide range of applications including wastewater...
Bioremediation of copper (Cu ) with immobilized Micrococcus luteus in polymer matrices has been broadly studied for a wide range of applications including wastewater treatment. Herein, the bioremediation efficiency based on modified immobilization techniques and by the addition of Cu is investigated. Porous composite nonwovens with living M. luteus (living polymer composites) are prepared by encapsulation of the bacterial cells in poly(vinyl alcohol) (PVA) microparticles (M. luteus/PVA microparticles) produced by spray drying method. The M. luteus/PVA microparticles are chemically cross-linked. The hydrogel microparticles with encapsulated M. luteus are embedded in a nonwoven of poly (lactic acid) (PLA) electrospun short fibers provided by wet-laid method. Two different models of composite nonwovens are reported, in which the place position of the hydrogel PVA microparticles with encapsulated M. luteus and PLA nonwoven can affect the bioremediation process.
Topics: Biodegradation, Environmental; Copper; Hydrogels; Micrococcus luteus; Microscopy, Electron, Scanning; Polyvinyl Alcohol
PubMed: 34414670
DOI: 10.1002/mabi.202100086 -
Frontiers in Molecular Biosciences 2019Bacterial uptake of DNA through type IV filaments is an essential component of natural competence in numerous gram-positive and gram-negative species. Recent advances in... (Review)
Review
Bacterial uptake of DNA through type IV filaments is an essential component of natural competence in numerous gram-positive and gram-negative species. Recent advances in the field have broadened our understanding of the structures used to take up extracellular DNA. Here, we review seminal experiments in the literature describing DNA binding by type IV pili, competence pili and the flp pili of ; collectively referred to here as type IV filaments. We compare the current state of the field on mechanisms of DNA uptake for these three appendage systems and describe the current mechanistic understanding of both DNA-binding and DNA-uptake by these versatile molecular machines.
PubMed: 30805346
DOI: 10.3389/fmolb.2019.00001 -
Journal of Fish Diseases Nov 2018Acute hepatopancreatic necrosis disease (AHPND) was first reported in China in 2009 and afterwards in Mexico in 2013. AHPND is caused by Vibrio parahaemolyticus and...
Acute hepatopancreatic necrosis disease (AHPND) was first reported in China in 2009 and afterwards in Mexico in 2013. AHPND is caused by Vibrio parahaemolyticus and affects Penaeus monodon and Litopenaeus vannamei shrimp cultures. The bacterium contains the pirA- and pirB-like genes in 69- to 70-Kb plasmids, which encode the toxins that produce the disease. The aim of this study was to determine whether pirA- and pirB-like genes existed in bacterial genera distinct from Vibrio before the first cases of AHPND were documented in Mexico. Two bacterial isolates were selected from shrimp farms in Nayarit in 2006 and analysed by nested-PCR to determine the presence of pirA- and pirB-like genes. The two isolates chosen did indeed show the presence of these genes, and those findings were confirmed by sequencing. Both strains matched to the bacterial species Micrococcus luteus. Results revealed two important situations: (a) the pirA- and pirB-like genes were present in a bacterial species that has not been reported previously (Micrococcus luteus); and (b) pirA- and pirB-like bacterial genes were present in Mexico before the first AHPND outbreak was reported in China.
Topics: Animals; Bacterial Proteins; Genes, Bacterial; Mexico; Micrococcus luteus; Penaeidae; Polymerase Chain Reaction
PubMed: 30051482
DOI: 10.1111/jfd.12874 -
International Journal of Biological... Sep 2021Marine microorganisms are reported to produce polyhydroxybutyrate (PHB) that has wide range of medical and industrial applications with the advantage of...
Marine microorganisms are reported to produce polyhydroxybutyrate (PHB) that has wide range of medical and industrial applications with the advantage of biodegradability. PHBs are synthesized as an energy and carbon storage element under metabolic pressure. The scope of this work is enhancing PHB production using marine microbial isolate, Micrococcus luteus by selectively optimizing various growth conditions such as different media components and growth parameters that influence the cell growth and PHB production were sampled. Micrococcus luteus produced 7.54 g/L of PHB utilizing glucose as a carbon source and ammonium sulphate as a nitrogen source with maximum efficiency. The same optimized operational conditions were further employed in batch fermentation over a time span of 72 h. Interestingly higher cell dry weight of 21.52 g/L with PHB yield of 12.18 g/L and 56.59% polymer content was observed in batch fermentation studies at 64 h. The chemical nature of the extracted polymer was validated with physio-chemical experiments and was at par with the commercially available PHB. This study will spotlight M. luteus as a potential source for large-scale industrial production of PHB with reducing environmental pollutions.
Topics: Butyrates; Fermentation; Geologic Sediments; Hydrogen-Ion Concentration; Hydroxybutyrates; Industrial Microbiology; Micrococcus luteus; Molecular Structure; Temperature; Time Factors
PubMed: 34246666
DOI: 10.1016/j.ijbiomac.2021.07.029 -
Natural Product Research Oct 2020A new isopimarane-type diterpenoid, crolaevinoid A, along with four known analogues was isolated from the twigs and leaves of . The structures of the isolated compounds...
A new isopimarane-type diterpenoid, crolaevinoid A, along with four known analogues was isolated from the twigs and leaves of . The structures of the isolated compounds were established on the basis of NMR and MS spectroscopic analyses. The isolated compounds were examined the antibacterial activities. Unfortunately, the compounds showed no antibacterial activity against , Methicillin-resistant , , , , and
Topics: Abietanes; Anti-Bacterial Agents; Croton; Diterpenes; Drug Evaluation, Preclinical; Magnetic Resonance Spectroscopy; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Molecular Structure; Plant Leaves; Spectrometry, Mass, Electrospray Ionization
PubMed: 30990080
DOI: 10.1080/14786419.2019.1596096 -
Scientific Reports Nov 2022This study investigated the mechanism of membrane damage by protocatechualdehyde (PCA) against Micrococcus luteus and assessed effects of PCA on the sensory and...
This study investigated the mechanism of membrane damage by protocatechualdehyde (PCA) against Micrococcus luteus and assessed effects of PCA on the sensory and physicochemical properties of pork. The mechanism of PCA inhibition on M. luteus was studied by determining the minimum inhibitory concentration (MIC) based on membrane potential, intracellular ATP concentration, intracellular pH, confocal laser scanning microscopy (CLSM), and field emission gun scanning electron microscopy (FEG-SEM). The results showed that the MIC of PCA against M. luteus was 1.25 mg/mL. Hyperpolarization of the bacterial cell membrane, a decrease in the intracellular ATP concentration, and intracellular pH indicated that PCA damaged the cell membrane of M. luteus. FEG-SEM observation revealed that PCA could cause surface collapse, cell membrane rupture, and content outflow of M. luteus. Additionally, PCA was found to inhibit increases in the total number of colonies, the thiobarbituric acid reactive substances (TBARS) value growth rate, and moisture mobility in raw pork. Additionally, it improved the color and texture of raw pork, all of which effectively prolonged its shelf life. This study will encourage the application of PCA as a natural antibacterial agent in the food industry.
Topics: Animals; Swine; Micrococcus luteus; Pork Meat; Red Meat; Adenosine Triphosphate
PubMed: 36344587
DOI: 10.1038/s41598-022-23309-3 -
Journal of Applied Microbiology Nov 2022To reveal the antibacterial mechanism of protocatechuic acid (PCA) against Micrococcus luteus.
AIM
To reveal the antibacterial mechanism of protocatechuic acid (PCA) against Micrococcus luteus.
METHODS AND RESULTS
M. luteus was exposed to PCA, and the antibacterial mechanism was revealed by measuring membrane potential, intracellular ATP and pH levels and transcriptome analysis. PCA induced the membrane potential depolarization of M. luteus, significantly decreased the intracellular ATP and pH levels of M. luteus and disrupted the integrity of the M. luteus cell membrane. Transcriptome analysis showed that PCA induced 782 differentially expressed genes (DEGs) of M. luteus. GO enrichment analysis revealed that the majority of DEGs are involved in pathways of metabolic process, cellular process, biological regulation and transport activity. In addition, PCA inhibited the growth of M. luteus in skimmed milk and extended the shelf life of skimmed milk.
CONCLUSION
PCA had good bactericidal activity against M. luteus through the mechanism of cell membrane disruption and metabolic process disorder.
SIGNIFICANCE AND IMPACT OF THE STUDY
PCA inhibits the growth of M. luteus in skimmed milk, suggesting that PCA is promising to be used as a novel preservative in food storage.
Topics: Micrococcus luteus; Gene Expression Profiling; Anti-Bacterial Agents; Adenosine Triphosphate; Micrococcus
PubMed: 35996816
DOI: 10.1111/jam.15743 -
International Journal of Systematic and... Nov 2019, and are phenotypically and genotypically closely related, and together comprise the group. In this study, the taxonomic relationships among , and were...
, and are phenotypically and genotypically closely related, and together comprise the group. In this study, the taxonomic relationships among , and were re-evaluated by using polyphasic approaches. The similarity values of the concatenated housekeeping gene (, and ) sequences shared by the type strains of , and ranged from 98.3 to 99.4 %. The average nucleotide identity, average amino acid identity and digital DNA‒DNA hybridization values among these three taxa were greater (97.1‒98.1 %, 96.8‒98.1 % and 75.0‒83.5 %, respectively) than the thresholds for bacterial species delineation, indicating that they belong to the same species, whereas those for were clearly lower than the thresholds. In addition, phenotypic and chemotaxonomic characterization results also support the synonymy of these three taxa. Therefore, we propose that and should be reclassified as later heterotypic synonyms of .
Topics: Bacterial Typing Techniques; Base Composition; DNA, Bacterial; Fatty Acids; Genes, Bacterial; Micrococcus; Micrococcus luteus; Nucleic Acid Hybridization; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA
PubMed: 31454307
DOI: 10.1099/ijsem.0.003654 -
Current Research in Microbial Sciences Dec 2021The proteomics and transcriptomic analysis of strain AS2 was carried out through 2D gel electrophoresis and RT-PCR. Seven protein spots were selected randomly from the...
The proteomics and transcriptomic analysis of strain AS2 was carried out through 2D gel electrophoresis and RT-PCR. Seven protein spots were selected randomly from the gel and identified through mass spectrometry. Four proteins including putative metal-dependent hydrolase TatD, thioredoxin reductase, DNA-directed RNA polymerase subunit alpha and chaperone protein DnaK were upregulated while superoxide dismutase [Mn], 3-oxoacyl-[acyl-carrier-protein] reductase FabG, and putative alkyl/aryl-sulfatase YjcS were down-regulated under arsenite stress. No significant difference was observed in gene expression analysis in the presence and absence of arsenite. The optimum arsenite processing ability was determined at 37°C (90%) and at pH 7 (92%). The maximum metal processing ability was determined at 250 mM arsenite/L (90%) while the minimum was estimated at 1250 mM arsenite/L (42%). The maximum arsenite removal ability of strain AS2 determined after 8 days was 68 and 82% from wastewater and distilled water, and the organism can be a good bioresource for green chemistry to eradicate environmental arsenite.
PubMed: 34841312
DOI: 10.1016/j.crmicr.2021.100020