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Experimental & Molecular Medicine Jan 2023Bacterial extracellular vesicles (EVs) have been shown to regulate various pulmonary diseases, but their functions in asthma remain uncertain. To demonstrate the...
Bacterial extracellular vesicles (EVs) have been shown to regulate various pulmonary diseases, but their functions in asthma remain uncertain. To demonstrate the clinical significance of Micrococcus luteus-derived EVs (MlEVs) in asthma, we enrolled 45 asthmatic patients (20 patients with neutrophilic asthma [NA], 25 patients with eosinophilic asthma [EA]) and 40 healthy controls (HCs). When the prevalence of IgG1 and IgG4 specific to MlEVs was evaluated in serum by ELISA, lower levels of MlEV-specific IgG4 (but not IgG1) were noted in asthmatic patients than in HCs. Among asthmatic patients, significantly lower levels of MIEV-specific IgG4 were noted in patients with NA than in those with EA. Moreover, there was a positive correlation between serum MlEV-specific IgG4 levels and FEV (%) values. In asthmatic C57BL/6 mice, MlEVs significantly attenuated neutrophilic airway inflammation by reducing the production of IL-1β and IL-17 in bronchoalveolar lavage fluid as well as the number of group 3 innate lymphoid cells (ILC3s) in lung tissues. To clarify the functional mechanism of MlEVs in NA, the effect of MlEVs on airway epithelial cells (AECs) and immune cells was investigated ex vivo. According to microarray analysis, MlEVs upregulated hsa-miR-4517 expression in AECs. Moreover, this miRNA could suppress IL-1β production by monocytes, resulting in the inhibition of ILC3 activation and neutrophil recruitment. These findings suggest that MlEVs could be a novel therapeutic agent for managing unresolved NA by regulating miRNA expression in AECs.
Topics: Mice; Animals; MicroRNAs; Micrococcus luteus; Immunity, Innate; Mice, Inbred C57BL; Lymphocytes; Asthma; Bronchoalveolar Lavage Fluid; Epithelial Cells; Extracellular Vesicles; Disease Models, Animal
PubMed: 36639716
DOI: 10.1038/s12276-022-00910-0 -
BMC Research Notes Jun 2024The purpose of this study was to evaluate antibacterial activity of pigment extracted from bacteria, isolated from soil samples. During the study, 20 soil samples were...
The purpose of this study was to evaluate antibacterial activity of pigment extracted from bacteria, isolated from soil samples. During the study, 20 soil samples were collected from different areas (forest, agriculture fields, river sides and dumping sites) of Kathmandu and Lalitpur districts which were processed for isolation of pigment producing bacteria by spread plate technique. The pigmented bacterial isolates were identified and enriched in nutrient broth. Then, pigment was extracted in 95% methanol as solvent, which was further characterized using UV-Vis Spectrophotometric and TLC analysis. The obtained crude pigment extract was processed to carry out the antimicrobial susceptibility assay using agar well diffusion method. Out of 13 total pigmented bacteria isolates, four different colored pigmented bacterial isolates (S4O, S11Y, S14P and S17G) which produced efficient pigment on nutrient agar were chosen and they were further processed. Among these isolates, S4O was identified as Staphylococcus aureus, S11Y was identified as Micrococcus luteus, S14P was identified as Micrococcus roseus and S17G was identified as Pseudomonas aeruginosa respectively. On characterization using UV-Vis Spectrophotometric and TLC analysis, the pigment extracted from isolates S4O, S11Y and S14P were found to be Carotenoids and from isolate S17G was found to be Pyocyanin in nature. The maximum antibacterial activity was shown against Staphylococcus aureus from all the four pigments extracts. The green color pigment extract from isolate S17G was found to be most effective against all the Gram-positive and Gram-negative test bacteria. This study suggests that these pigment extracts from pigmented bacteria may have beneficial antibacterial roles that can be exploited in controlling unwanted bacterial growth.
Topics: Anti-Bacterial Agents; Soil Microbiology; Pigments, Biological; Microbial Sensitivity Tests; Staphylococcus aureus; Pseudomonas aeruginosa; Bacteria; Micrococcus luteus
PubMed: 38898523
DOI: 10.1186/s13104-024-06834-4 -
Microorganisms Jul 2022Four aerobic bacteria with bacteriolytic capabilities were isolated from the brackish water site Strait Uzynaral of Lake Balkhash in Kazakhstan. The morphology and...
Four aerobic bacteria with bacteriolytic capabilities were isolated from the brackish water site Strait Uzynaral of Lake Balkhash in Kazakhstan. The morphology and physiology of the bacterial isolates have subsequently been analyzed. Using matrix assisted laser desorption ionization-time of flight mass spectrum and partial 16S rRNA gene sequence analyses, three of the isolates have been identified as and one as . We determined the capability of both species to lyse pre-grown cells of the Gram-negative strains SBUG 24 and SBUG 13 as well as the Gram-positive strains SBUG 16 and SBUG 321 on solid media. The bacteriolysis process was analyzed by creating growth curves and electron micrographs of co-cultures with the bacteriolytic isolates and the lysis sensitive strain SBUG 321 in nutrient-poor liquid media. One metabolite of was isolated and structurally characterized by various chemical structure determination methods. It is a novel antibiotic substance.
PubMed: 36013937
DOI: 10.3390/microorganisms10081519 -
Molecules (Basel, Switzerland) Apr 2017The formulation, characterization, and anticipated antibacterial properties of hemp seed oil and its emulsions were investigated. The oil obtained from the seeds of L....
The formulation, characterization, and anticipated antibacterial properties of hemp seed oil and its emulsions were investigated. The oil obtained from the seeds of L. in refined and unrefined form was characterized using iodine, saponification, acid values, and gas chromatography, and was employed for the preparation of stable oil-in-water emulsions. The emulsions were prepared using pairs of non-ionic surfactants (Tween, Span). The effects of the emulsification method (spontaneous emulsification vs. high-intensity stirring), hydrophilic lipophilic balance (HLB), type and concentration of surfactant, and oil type on the size and distribution of the emulsion particles were investigated. It was found that the ability to form stable emulsions with small, initial particle sizes is primarily dependent on the given method of preparation and the HLB value. The most efficient method of emulsification that afforded the best emulsions with the smallest particles (151 ± 1 nm) comprised the high-energy method, and emulsions stable over the long-term were observed at HBL 9 with 10 wt % concentration of surfactants. Under high-intensity emulsification, refined and unrefined oils performed similarly. The oils as well as their emulsions were tested against the growth of selected bacteria using the disk diffusion and broth microdilution methods. The antibacterial effect of hemp seed oil was documented against and subsp. . The formulated emulsions did not exhibit the antibacterial activity that had been anticipated.
Topics: Anti-Bacterial Agents; Cannabis; Emulsions; Hydrophobic and Hydrophilic Interactions; Microbial Sensitivity Tests; Micrococcus luteus; Particle Size; Plant Extracts; Plant Oils; Seeds; Staphylococcus aureus
PubMed: 28448475
DOI: 10.3390/molecules22050700 -
International Journal of Molecular... Aug 2021DNA is a polymeric macromolecule that can display a variety of backbone conformations. While the classical B-DNA is a right-handed double helix, Z-DNA is a left-handed...
DNA is a polymeric macromolecule that can display a variety of backbone conformations. While the classical B-DNA is a right-handed double helix, Z-DNA is a left-handed helix with a zig-zag orientation. The Z conformation depends upon the base sequence, base modification and supercoiling and is considered to be transient. To determine whether the presence of Z-DNA can be detected immunochemically, the binding of monoclonal and polyclonal anti-Z-DNA antibodies to a panel of natural DNA antigens was assessed by an ELISA using brominated poly(dG-dC) as a control for Z-DNA. As these studies showed, among natural DNA tested ( calf thymus, , salmon sperm, lambda phage), micrococcal (MC) DNA showed the highest binding with both anti-Z-DNA preparations, and DNA showed binding with the monoclonal anti-DNA preparation. The specificity for Z-DNA conformation in MC DNA was demonstrated by an inhibition binding assay. An algorithm to identify propensity to form Z-DNA indicated that DNA from could form Z-DNA, a prediction confirmed by immunoassay. Together, these findings indicate that anti-Z-DNA antibodies can serve as probes for the presence of Z-DNA in DNA of various species origin and that the content of Z-DNA varies significantly among DNA sources.
Topics: Animals; Antibodies, Monoclonal; Antibody Specificity; DNA, Z-Form; Escherichia coli; Female; Humans; Male; Micrococcus luteus; Nucleic Acid Conformation; Placenta; Pregnancy; Salmon; Sheep; Species Specificity; Spermatozoa
PubMed: 34445637
DOI: 10.3390/ijms22168931 -
Chinese Medical Journal Jun 2016Early embryonic developmental arrest is the most commonly understudied adverse outcome of pregnancy. The relevance of intrauterine infection to spontaneous embryonic...
BACKGROUND
Early embryonic developmental arrest is the most commonly understudied adverse outcome of pregnancy. The relevance of intrauterine infection to spontaneous embryonic death is rarely studied and remains unclear. This study aimed to investigate the relationship between intrauterine bacterial infection and early embryonic developmental arrest.
METHODS
Embryonic chorion tissue and uterine swabs for bacterial detection were obtained from 33 patients who underwent artificial abortion (control group) and from 45 patients who displayed early embryonic developmental arrest (trial group).
RESULTS
Intrauterine bacterial infection was discovered in both groups. The infection rate was 24.44% (11/45) in the early embryonic developmental arrest group and 9.09% (3/33) in the artificial abortion group. Classification analysis revealed that the highest detection rate for Micrococcus luteus in the early embryonic developmental arrest group was 13.33% (6/45), and none was detected in the artificial abortion group. M. luteus infection was significantly different between the groups (P < 0.05 as shown by Fisher's exact test). In addition, no correlation was found between intrauterine bacterial infection and history of early embryonic developmental arrest.
CONCLUSIONS
M. luteus infection is related to early embryonic developmental arrest and might be one of its causative factors.
Topics: Abortion, Induced; Abortion, Spontaneous; Bacterial Infections; Female; Humans; Micrococcus luteus; Pregnancy; Uterus
PubMed: 27270541
DOI: 10.4103/0366-6999.183411 -
Negative Correlation between Lipid Content and Antibiotic Activity in : General Rule and Exceptions.Antibiotics (Basel, Switzerland) May 2020Streptomycetes are well known antibiotic producers and are among the rare prokaryotes able to store carbon as lipids. Previous comparative studies of the weak antibiotic...
Streptomycetes are well known antibiotic producers and are among the rare prokaryotes able to store carbon as lipids. Previous comparative studies of the weak antibiotic producer with its mutant and with , which both produce antibiotics, suggested the existence of a negative correlation between total lipid content and the ability to produce antibiotics. To determine whether such a negative correlation can be generalized to other species, fifty-four strains were picked randomly and grown on modified R2YE medium, limited in phosphate, with glucose or glycerol as the main carbon source. The total lipid content and antibiotic activity against were assessed for each strain. This study revealed that the ability to accumulate lipids was not evenly distributed among strains and that glycerol was more lipogenic than glucose and had a negative impact on antibiotic biosynthesis. Furthermore, a statistically significant negative Pearson correlation between lipid content and antibiotic activity could be established for most strains, but a few strains escape this general law. These exceptions are likely due to limits and biases linked to the type of test used to determine antibiotic activity, which relies exclusively on sensitivity. They are characterized either by high lipid content and high antibiotic activity or by low lipid content and undetectable antibiotic activity against . Lastly, the comparative genomic analysis of two strains with contrasting lipid content, and both named (DSM 41,481 and DSM 40,868, which we found to be phylogenetically related to ) indicated that some genetic differences in various pathways related to the generation/consumption of acetylCoA could be responsible for such a difference.
PubMed: 32466356
DOI: 10.3390/antibiotics9060280 -
Proceedings of the National Academy of... May 1978Two active components alpha and beta of micrococcus luteus DNA gyrase, of peptide weights of 115,000 and 97,000, respectively, have been purified. Each individual...
Two active components alpha and beta of micrococcus luteus DNA gyrase, of peptide weights of 115,000 and 97,000, respectively, have been purified. Each individual component exhibits little DNA gyrase activity; the ATP-dependent negative supercoiling of a covalently closed circular DNA duplex is catalyzed by a combination of the two. Covalent closure by Escherichia coli ligase of a circular DNA containing single-chain scissions, when carried out in the presence of a combination of the DNA gyrase components alpha and beta, gives a positively supercoiled DNA upon removal of the bound protein molecules. ATP was not present during the ligase treatment; therefore the positive supercoiling of DNA observed is a result of the binding of gyrase molecules, presumably as multi-subunit oligomers, during the ligation step. This is in contrast to the negative supercoiling of DNA catalyzed by gyrase in the presence of ATP. A model in which negative supercoiling of DNA is achieved by ATP-modulated repetitive wrapping of the DNA around gyrase is described. The model also suggests a plausible mode of action by which translocation of a DNA along its helix axis can be actively driven by an ATPase.
Topics: Adenosine Triphosphate; Anti-Bacterial Agents; DNA, Bacterial; DNA, Superhelical; Macromolecular Substances; Magnesium; Micrococcus; Models, Chemical; Molecular Weight; Nucleic Acid Conformation; Potassium; Spermidine
PubMed: 276855
DOI: 10.1073/pnas.75.5.2098 -
Infection and Immunity Apr 2001Teichuronic acid (TUA), a component of the cell walls of the gram-positive organism Micrococcus luteus (formerly Micrococcus lysodeikticus), induced inflammatory...
Teichuronic acid (TUA), a component of the cell walls of the gram-positive organism Micrococcus luteus (formerly Micrococcus lysodeikticus), induced inflammatory cytokines in C3H/HeN mice but not in lipopolysaccharide (LPS)-resistant C3H/HeJ mice that have a defect in the Toll-like receptor 4 (TLR4) gene, both in vivo and in vitro, similarly to LPS (T. Monodane, Y. Kawabata, S. Yang, S. Hase, and H. Takada, J. Med. Microbiol. 50:4-12, 2001). In this study, we found that purified TUA (p-TUA) induced tumor necrosis factor alpha (TNF-alpha) in murine monocytic J774.1 cells but not in mutant LR-9 cells expressing membrane CD14 at a lower level than the parent J774.1 cells. The TNF-alpha-inducing activity of p-TUA in J774.1 cells was completely inhibited by anti-mouse CD14 monoclonal antibody (MAb). p-TUA also induced interleukin-8 (IL-8) in human monocytic THP-1 cells differentiated to macrophage-like cells expressing CD14. Anti-human CD14 MAb, anti-human TLR4 MAb, and synthetic lipid A precursor IV(A), an LPS antagonist, almost completely inhibited the IL-8-inducing ability of p-TUA, as well as LPS, in the differentiated THP-1 cells. Reduced p-TUA did not exhibit any activities in J774.1 or THP-1 cells. These findings strongly suggested that M. luteus TUA activates murine and human monocytic cells in a CD14- and TLR4-dependent manner, similar to LPS.
Topics: Animals; Antibodies, Monoclonal; Cell Line; Drosophila Proteins; Humans; Interleukin-8; Lipopolysaccharide Receptors; Membrane Glycoproteins; Mice; Micrococcus luteus; Monocytes; Receptors, Cell Surface; Toll-Like Receptor 4; Toll-Like Receptors; Tumor Necrosis Factor-alpha; Uronic Acids
PubMed: 11254554
DOI: 10.1128/IAI.69.4.2025-2030.2001 -
IScience Oct 2023Hen egg white lysozyme (HEWL) was exploited for the synthesis of β-amino carbonyl compounds through a direct and three-component Mannich reaction in aqueous, confirming...
Hen egg white lysozyme (HEWL) was exploited for the synthesis of β-amino carbonyl compounds through a direct and three-component Mannich reaction in aqueous, confirming high chemoselectivity toward imine. In order to further extend the applications of the enzyme, HEWL was encapsulated using a metal-organic framework (MOF). The reactivity, stereoselectivity, and reusability of the encapsulated enzyme were investigated. The reaction was significantly enhanced as compared to the non-encapsulated enzyme. A mutated version of the enzyme, containing Asp52Ala (D52A), lacking important catalytical residue, has lost the bacterial site activity against (. ) while the D52A variant displayed an increased rate of the Mannich reaction, indicating a different catalytical residue involved in the promiscuous reaction. Based on site-directed mutagenesis, molecular docking, and molecular dynamic studies, it was proposed that π-stacking, H-bond interactions, and the presence of water in the active site may play crucial roles in the mechanism of the reaction.
PubMed: 37744039
DOI: 10.1016/j.isci.2023.107807