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Frontiers in Immunology 2021The Toll-like receptor 4 (TLR4)/myeloid differentiation protein-2 (MD-2) complex is considered the major receptor of the innate immune system to recognize...
The Toll-like receptor 4 (TLR4)/myeloid differentiation protein-2 (MD-2) complex is considered the major receptor of the innate immune system to recognize lipopolysaccharides (LPSs). However, some atypical LPSs with different lipid A and core saccharide moiety structures and compositions than the well-studied enterobacterial LPSs can induce a TLR2-dependent response in innate immune cells. , an opportunistic pathogen, presents an atypical LPS. In this study, we found that LPS exhibits a weak inflammatory activity compared to LPS and, more importantly, is a specific TLR4/TLR2 agonist, able to signal through both receptors. Molecular docking analysis of LPS predicts a favorable formation of a TLR2/TLR4/MD-2 heterodimer complex, which was experimentally confirmed by fluorescence resonance energy transfer (FRET) in cells. Interestingly, the core saccharide plays an important role in this interaction. This study reveals for the first time TLR4/TLR2 heterodimerization that is induced by atypical LPS and may help to escape from recognition by the innate immune system.
Topics: Animals; Cell Line; Endotoxins; HEK293 Cells; Humans; Immunity, Innate; Inflammation; Lipid A; Lipopolysaccharides; Mice, Inbred C57BL; Mice, Knockout; Molecular Docking Simulation; Toll-Like Receptor 2; Toll-Like Receptor 4; Mice
PubMed: 35140704
DOI: 10.3389/fimmu.2021.748303 -
3 Biotech Jun 2023The increase in the generation of chicken feathers, due to the large production of the poultry industry, has created the need to search for ecologically safer ways to...
The increase in the generation of chicken feathers, due to the large production of the poultry industry, has created the need to search for ecologically safer ways to manage these residues. As a sustainable alternative for recycling keratin waste, we investigated the ability of the bacterium to hydrolyze chicken feathers and the valorization of the resulting enzymes and protein hydrolysate. In submerged fermentation with three different inoculum sizes (2.5, 5.0, and 10.0 mg of bacterial cells per 50 mL of medium), the fastest degradation of feathers was achieved with 5.0 mg cells, in which a complete decomposition of the substrate (96 h) and earlier peaks of keratinolytic and caseinolytic activities were detected. In the resulting protein hydrolysate, we noticed antioxidant and Fe and Cu chelating activities. ABTS scavenging, Fe-reducing ability and metal chelating activities of the fermentative samples followed the same trend of feather degradation; as feather mass decreased in the media, these activities increased. Furthermore, we noticed about 47% and 60% dispersion of established 7-day biofilms formed by after enzymatic treatment for 5 h and 24 h, respectively. These findings highlight the potential use of this bacterium as an environmentally friendly alternative to treat this poultry waste and offer valuable products.
PubMed: 37220603
DOI: 10.1007/s13205-023-03619-7 -
BMC Infectious Diseases Dec 2021Ochrobactrum spp. are non-fermenting, Gram-negative bacilli that are regarded as emerging human pathogens of low virulence that can cause infections. The first...
BACKGROUND
Ochrobactrum spp. are non-fermenting, Gram-negative bacilli that are regarded as emerging human pathogens of low virulence that can cause infections. The first identified case of Ochrobactrum intermedium was reported in 1998 in a liver transplantation patient with liver abcess. There are no reports of infections in pediatric patients. Here, we report the first case of O. intermedium bacteremia in a pediatric patient.
CASE PRESENTATION
A two and a half years old male was admitted with fever, chills and nausea. He had been diagnosed as pineoblastoma and underwent surgical resection and chemotherapy. O. intermedium was isolated from his blood cultures and identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), however, the Vitek II automated system failed to identify the organism. Then the pathogen was confirmed by 16S rDNA sequencing and average nucleotide identity result (ANI) confirmed the precise identification of O. intermedium at genomic level. In addition, the patient recovered well after antibiotic combined therapy.
CONCLUSIONS
This, to our knowledge, is the first case of O. intermedium bacteremia in a pediatric patient with malignant tumor. Traditional biochemical identification methods such as API 20NE or VITEK2 system cannot differentiate O. anthropi and O. intermedium. MALDI-TOF may be a promising tool for rapid identification of microorganisms such as O. intermedium.
Topics: Bacteremia; Child, Preschool; Gram-Negative Bacterial Infections; Humans; Male; Neoplasms; Ochrobactrum
PubMed: 34906070
DOI: 10.1186/s12879-021-06938-3 -
International Journal of Molecular... Mar 2023Digital dermatitis (DD) is the second most prevalent disease in dairy cattle. It causes significant losses for dairy breeders and negatively impacts cows' welfare and...
Digital dermatitis (DD) is the second most prevalent disease in dairy cattle. It causes significant losses for dairy breeders and negatively impacts cows' welfare and milk yield. Despite this, its etiology has not been entirely identified, and available data are limited. Antibiotic therapy is a practical method for managing animal health, but overuse has caused the evolution of antibiotic-resistant bacteria, leading to a loss in antimicrobial efficacy. The antimicrobial properties of metal nanoparticles (NPs) may be a potential alternative to antibiotics. The aim of this study was to determine the biocidal properties of AgNPs, CuNPs, AuNPs, PtNPs, FeNPs, and their nanocomposites against pathogens isolated from cows suffering from hoof diseases, especially DD. The isolated pathogens included , I, II, , and . Cultures were prepared in aerobic and anaerobic environments. The viability of the pathogens was then determined after applying nanoparticles at various concentrations. The in vitro experiment showed that AgNPs and CuNPs, and their complexes, had the highest biocidal effect on pathogens. The NPs' biocidal properties and their synergistic effects were confirmed, which may forecast their use in the future treatment and the prevention of lameness in cows, especially DD.
Topics: Female; Cattle; Animals; Digital Dermatitis; Lameness, Animal; Gold; Metal Nanoparticles; Anti-Infective Agents; Anti-Bacterial Agents; Cattle Diseases; Dairying
PubMed: 37047119
DOI: 10.3390/ijms24076146 -
Cureus Apr 2021species are gram-negative, non-lactose fermenting, aerobic bacilli closely related to genus. () is an emergent human pathogen that is difficult to differentiate from...
species are gram-negative, non-lactose fermenting, aerobic bacilli closely related to genus. () is an emergent human pathogen that is difficult to differentiate from other species by conventional methods. It is known to infect immunocompromised hosts, has the propensity for abscess formation, and is known for its multidrug resistance. We describe the case of an 84-year-old woman with a background of primary sclerosing cholangitis who presented with fatigue, fever, and syncope. Blood cultures grew . Magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography were consistent with cholangitis. Cultures from the biliary duct confirmed the same microorganism. The patient was successfully treated with minocycline. Although rare, should be considered as a differential diagnosis in patients with biliary and gut pathology, particularly in immunocompromised patients.
PubMed: 34046280
DOI: 10.7759/cureus.14648 -
Microbiology Resource Announcements Apr 2022Brucella intermedia/Ochrobactrum intermedium strain DF13 was isolated from Brazilian soil and is able to degrade 2,4-dichlorophenoxyacetic acid (2,4-D). Here, we report...
Brucella intermedia/Ochrobactrum intermedium strain DF13 was isolated from Brazilian soil and is able to degrade 2,4-dichlorophenoxyacetic acid (2,4-D). Here, we report on its genome sequence, with 4,570,268 bp and a 57.8% G+C content.
PubMed: 35343769
DOI: 10.1128/mra.01105-21 -
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 -
New Microbes and New Infections Mar 2024is recognized as a rare emerging opportunistic pathogen mostly related with bloodstream infections. In this report, we describe the first clinical case of pneumonia due...
is recognized as a rare emerging opportunistic pathogen mostly related with bloodstream infections. In this report, we describe the first clinical case of pneumonia due to The case involved a 71-year old tetraplegic man hospitalized for vertebral fractures after falling from a ladder.
PubMed: 38357689
DOI: 10.1016/j.nmni.2024.101224 -
International Journal of... 2022Inorganic arsenic (As) is a toxic and carcinogenic pollutant that has long-term impacts on environmental quality and human health. plants hyperaccumulate As from soils....
Inorganic arsenic (As) is a toxic and carcinogenic pollutant that has long-term impacts on environmental quality and human health. plants hyperaccumulate As from soils. Soil bacteria are critical for As-uptake by . We examined the use of taxonomically diverse soil bacteria to modulate As speciation in soil and their effect on As-uptake by . Aqueous media inoculated with MK800041, MK344656, MK345459, MK346993 or MK346997 resulted in the oxidation of 5-30% As(III) and a 49-79% reduction of As(V). Soil inoculated with increased extractable As(III) and As(V) from 0.5 and 0.09 in controls to 0.9 and 0.39 mg As kg soil dry weight, respectively. Moreover, and plants inoculated with , , strains, and strains MK344655, MK346994, MK346997, significantly increased As-uptake by 43, 32, 12, 18, 16, and 14%, respectively, compared to controls. The greatest As-accumulation (1.9 ± 0.04 g kg frond Dwt) and bioconcentration factor (16.3 ± 0.35) was achieved in plants inoculated with . Our findings indicate that the tested bacterial strains can increase As-availability in soils, thus enhancing As-accumulation by . , a well-known As-hyperaccumulator, has the remarkable ability to accumulate higher levels of As in their above-ground biomass. The As-tolerant bacteria-plant interactions play a significant role in bioremediation by mediating As-redox and controlling As-availability and uptake by . Our studies indicated that most of the tested bacterial strains isolated from As-impacted soil significantly enhanced As-uptake by . oxidized 20% of As(III) and reduced 50% of As(V), increased As-extraction from soils, and increased As-uptake by 43% greater compared with control. Therefore, these strains associated with can be used in large-scale field applications to remediate As-contaminated soil.
Topics: Arsenic; Bacteria; Biodegradation, Environmental; Pteris; Soil; Soil Pollutants
PubMed: 34334062
DOI: 10.1080/15226514.2021.1951654 -
International Journal of Molecular... Jan 2023(formerly ), a non-fermentative bacterium, has been isolated from animals and human clinical specimens. It is naturally resistant to polymyxins, including colistin...
(formerly ), a non-fermentative bacterium, has been isolated from animals and human clinical specimens. It is naturally resistant to polymyxins, including colistin (CO), and may cause opportunistic infections in humans. We isolated six strains from Senegalese monkey stool. In order to determine whether an efflux pump mechanism was involved in CO resistance in we evaluated the effects of verapamil (VRP), reserpine (RSP), phe-arg β-naphthylamide dihydrochloride (PAβN) and carbonyl cyanide 3-chloro phenyl hydrazone (CCCP), four efflux pump inhibitors, on these colistin-resistant strains. Using the broth microdilution method, a CO and CCCP combination of 2 µg/mL and 10 µg/mL, respectively, significantly reduced the CO minimal inhibitory concentration (MIC) of , supporting an efflux pump mechanism. In contrast, VRP, PAβN and RSP did not restore CO susceptibility. A time kill assay showed a bactericidal effect of the CO-CCCP combination. Genomic analysis revealed a potential implication in the CO resistance mechanism of some conserved efflux pumps, such as YejABEF, NorM and EmrAB, as previously reported in other bacteria. An inhibitory effect of the CO-CCCP combination was observed on biofilm formation using the crystal violet method. These results suggest that the intrinsic CO resistance in is linked to an efflux pump mechanism and that the synergistic effect of CO-CCCP may open a new field to identify new treatments to restore antibiotic efficacy in humans.
Topics: Humans; Colistin; Carbonyl Cyanide m-Chlorophenyl Hydrazone; Hydrazones; Anti-Bacterial Agents; Brucella; Microbial Sensitivity Tests
PubMed: 36768429
DOI: 10.3390/ijms24032106