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Current Microbiology Jun 2024Garlic (Allium sativum L.), particularly its volatile essential oil, is widely recognized for medicinal properties. We have evaluated the efficacy of Indian Garlic...
Garlic (Allium sativum L.), particularly its volatile essential oil, is widely recognized for medicinal properties. We have evaluated the efficacy of Indian Garlic Essential Oil (GEO) for antimicrobial and antibiofilm activity and its bioactive constituents. Allyl sulfur-rich compounds were identified as predominant phytochemicals in GEO, constituting 96.51% of total volatile oils, with 38% Diallyl trisulphide (DTS) as most abundant. GEO exhibited significant antibacterial activity against eleven bacteria, including three drug-resistant strains with minimum inhibitory concentrations (MICs) ranging from 78 to 1250 µg/mL. In bacterial growth kinetic assay GEO effectively inhibited growth of all tested strains at its ½ MIC. Antibiofilm activity was evident against two important human pathogens, S. aureus and P. aeruginosa. Mechanistic studies demonstrated that GEO disrupts bacterial cell membranes, leading to the release of nucleic acids, proteins, and reactive oxygen species. Additionally, GEO demonstrated potent antioxidant activity at IC 31.18 mg/mL, while its isolated constituents, Diallyl disulphide (DDS) and Diallyl trisulphide (DTS), showed effective antibacterial activity ranging from 125 to 500 µg/mL and 250-1000 µg/mL respectively. Overall, GEO displayed promising antimicrobial and antibiofilm activity against enteric bacteria, suggesting its potential application in the food industry.
Topics: Garlic; Oils, Volatile; Antioxidants; Anti-Bacterial Agents; Biofilms; Microbial Sensitivity Tests; Staphylococcus aureus; Allyl Compounds; Phytochemicals; Sulfides; Bacteria; Pseudomonas aeruginosa; Disulfides; India; Plant Oils; Humans; Plant Extracts
PubMed: 38940852
DOI: 10.1007/s00284-024-03753-2 -
International Journal of Systematic and... Jun 2024A Gram-negative, strictly aerobic bacterial strain was isolated from asymptomatic leaf tissue of a wild yam plant. Optimal growth was observed at 28 °C and pH 7, and...
A Gram-negative, strictly aerobic bacterial strain was isolated from asymptomatic leaf tissue of a wild yam plant. Optimal growth was observed at 28 °C and pH 7, and catalase and oxidase activities were detected. Polyphasic taxonomic and comparative genomics revealed that strain LMG 33091 represents a novel species of . The nearest phylogenetic neighbours of strain LMG 33091 were NBRC 14164 (with 99.79 % 16S rRNA sequence identity), KL28 (99.28 %) and (99.07 %) ATCC 23835. MALDI-TOF MS analysis yielded distinct profiles for strain LMG 33091 and the nearest phylogenetic neighbours. Average nucleotide identity analyses between the whole genome sequence of strain LMG 33091 and of the type strains of its nearest-neighbour taxa yielded values below the species delineation threshold and thus confirmed that the strain represented a novel species, for which we propose the name sp. nov., with strain LMG 33091 (=GMI12077= CFBP 9143) as the type strain.
Topics: Pseudomonas; Phylogeny; RNA, Ribosomal, 16S; DNA, Bacterial; Plant Leaves; Sequence Analysis, DNA; Bacterial Typing Techniques; Dioscorea; Whole Genome Sequencing; Base Composition; Fatty Acids; Genome, Bacterial
PubMed: 38940814
DOI: 10.1099/ijsem.0.006395 -
The endosymbiont increases resistance to pathogens by enhancing iron sequestration and melanization.MBio Jun 2024Facultative endosymbiotic bacteria, such as and species, are commonly found in association with insects and can dramatically alter their host physiology. Many...
UNLABELLED
Facultative endosymbiotic bacteria, such as and species, are commonly found in association with insects and can dramatically alter their host physiology. Many endosymbionts are defensive and protect their hosts against parasites or pathogens. Despite the widespread nature of defensive insect symbioses and their importance for the ecology and evolution of insects, the mechanisms of symbiont-mediated host protection remain poorly characterized. Here, we utilized the fruit fly and its facultative endosymbiont to characterize the mechanisms underlying symbiont-mediated host protection against bacterial and fungal pathogens. Our results indicate a variable effect of on infection outcome, with endosymbiont-harboring flies being more resistant to , and but more sensitive or as sensitive as endosymbiont-free flies to the infections with species. Further focusing on the protective effect, we identified Transferrin-mediated iron sequestration induced by as being crucial for the defense against and . In the case of , enhanced melanization in -harboring flies plays a major role in protection. Both iron sequestration and melanization induced by require the host immune sensor protease Persephone, suggesting a role of proteases secreted by the symbiont in the activation of host defense reactions. Hence, our work reveals a broader defensive range of than previously appreciated and adds nutritional immunity and melanization to the defensive arsenal of symbionts.
IMPORTANCE
Defensive endosymbiotic bacteria conferring protection to their hosts against parasites and pathogens are widespread in insect populations. However, the mechanisms by which most symbionts confer protection are not fully understood. Here, we studied the mechanisms of protection against bacterial and fungal pathogens mediated by the endosymbiont . We demonstrate that besides the previously described protection against wasps and nematodes, also confers increased resistance to pathogenic bacteria and fungi. We identified -induced iron sequestration and melanization as key defense mechanisms. Our work broadens the known defense spectrum of and reveals a previously unappreciated role of melanization and iron sequestration in endosymbiont-mediated host protection. We propose that the mechanisms we have identified here may be of broader significance and could apply to other endosymbionts, particularly to , and potentially explain their protective properties.
PubMed: 38940615
DOI: 10.1128/mbio.00936-24 -
Journal of Bacteriology Jun 2024The cystic fibrosis (CF) lung environment is conducive to the colonization of bacteria as polymicrobial biofilms, which are associated with poor clinical outcomes for...
UNLABELLED
The cystic fibrosis (CF) lung environment is conducive to the colonization of bacteria as polymicrobial biofilms, which are associated with poor clinical outcomes for persons with CF (pwCF). spp. are highly prevalent in the CF airway, but its role in the CF lung microbiome is poorly understood. Some studies have shown spp. to be associated with better clinical outcomes for pwCF, while others show that high abundance of spp. is correlated with exacerbations. Our lab previously reported a polymicrobial culture system consisting of four CF-relevant pathogens that can be used to study microbial behavior in a more clinically relevant setting. Here, we use this model system to identify genetic pathways that are important for survival in the context of the polymicrobial community. We identified genes related to reactive oxygen species as differentially expressed in monoculture versus growth of this microbe in the mixed community. Genetic studies identified Dpr as important for survival in the community. We show that Dpr, a DNA-binding ferritin-like protein, and PerR, a peroxide-responsive transcriptional regulator of Dpr, are important for protecting from phenazine-mediated toxicity in co-culture with and when exposed to hydrogen peroxide, both of which mimic the CF lung environment. Characterizing such interactions in a clinically relevant model system contributes to our understanding of microbial behavior in the context of polymicrobial biofilm infections.
IMPORTANCE
spp. are recognized as a highly prevalent pathogen in cystic fibrosis (CF) airway infections. However, the role of this microbe in clinical outcomes for persons with CF is poorly understood. Here, we leverage a polymicrobial community system previously developed by our group to model CF airway infections as a tool to investigate a - interaction involving reactive oxygen species (ROS). We show that protection against ROS is required for survival in a clinically relevant polymicrobial system. Using this model system to study interspecies interactions contributes to our broader understanding of the complex role of spp. in the CF lung.
PubMed: 38940597
DOI: 10.1128/jb.00176-24 -
Microbiology Resource Announcements Jun 2024Here, we report the draft genome sequence of endophytic sp. 102515 isolated from collected from Logan, UT, USA. The genome is composed of 36 contigs and around 4.9 Mbp...
Here, we report the draft genome sequence of endophytic sp. 102515 isolated from collected from Logan, UT, USA. The genome is composed of 36 contigs and around 4.9 Mbp in size. The GC content is 66% with an length of 918.9 kbp and count of 2.
PubMed: 38940526
DOI: 10.1128/mra.00139-24 -
Journal of Global Health Jun 2024Considering the large population of bronchiectasis and chronic obstructive pulmonary disease (COPD) patients in China, we aimed to conduct a thorough analysis that...
Analysis of clinical characteristics, prognosis and influencing factors in patients with bronchiectasis-chronic obstructive pulmonary disease overlap syndrome: A prospective study for more than five years.
BACKGROUND
Considering the large population of bronchiectasis and chronic obstructive pulmonary disease (COPD) patients in China, we aimed to conduct a thorough analysis that investigates the clinical characteristics and prognosis of bronchiectasis-COPD overlap syndrome (BCOS). Further, we aimed to explore factors associated with acute exacerbation and death in BCOS, which may be of value in its early diagnosis and intervention.
METHODS
We recruited inpatients with COPD from the second Xiangya Hospital of Central South University in China in August 2016, with follow-up until March 2022. Patients in the BCOS group had to meet the criteria for diagnosing bronchiectasis. We used self-completion questionnaires, clinical records, and self-reported data as primary data collection methods. We used Kaplan-Meier survival analyses and Cox proportional hazard models to assess the risk of severe acute exacerbation and death for BCOS during the follow-up period.
RESULTS
A total of 875 patients were included and followed up. Patients in the BCOS group had more females, fewer smokers, lower discharge COPD assessment test (CAT) scores, lower forced vital capacity (FVC), a higher likelihood of co-occurring active tuberculosis, higher levels of eosinophils and inflammatory markers, and a higher rate of positive sputum cultures for Pseudomonas aeruginosa than patients in the COPD-only group. Patients in the acute exacerbation group (AE+) were found to have lower body mass index (BMI), more frequent acute exacerbations, higher modified Medical Research Council (mMRC) dyspnoea grade on admission, higher inflammatory markers, lower FVC, higher rates of using inhaled bronchodilators, and higher rates of both positive and Pseudomonas aeruginosa positive sputum cultures. Patients in the 'death' group were older, had a lower BMI, had spent longer time in the hospital, had higher mMRC dyspnoea grade and CAT scores upon admission and discharge, had higher levels of inflammatory markers, lower rates of using inhaled bronchodilators, were more likely to have a combination of pulmonary heart disease and obsolete pulmonary tuberculosis, as well as a higher rate of fungus-positive sputum cultures. Both erythrocyte sedimentation rate at baseline and Pseudomonas aeruginosa culture positivity were confirmed as independent predictors of severe acute exacerbation in multivariate analysis during the years of follow-up. Fungus culture positivity baseline blood urea nitrogen, baseline lymphocyte count, comorbidities with obsolete pulmonary tuberculosis and comorbidities with pulmonary heart disease were verified as independent predictors of death in multivariate analysis during the years of follow-up. Kaplan-Meier curves under survival analysis demonstrated no statistically significant difference in mortality between the COPD and the BCOS groups at the full one, two, and three years of follow-up.
CONCLUSIONS
Patients with BCOS present with reduced lung function, increased susceptibility to different complications, elevated blood eosinophils and inflammatory markers, and elevated rates of positive Pseudomonas aeruginosa cultures. These distinctive markers are linked to a greater risk of severe acute exacerbations and mortality.
Topics: Humans; Female; Pulmonary Disease, Chronic Obstructive; Male; Bronchiectasis; Middle Aged; Prospective Studies; Aged; Prognosis; China; Risk Factors; Syndrome; Disease Progression
PubMed: 38940273
DOI: 10.7189/jogh.14.04129 -
Frontiers in Microbiology 2024Symbiotic microbial have a significant impact on the growth and metabolism of medicinal plants. is a very functionally rich medicinal herb; however, its microbial...
INTRODUCTION
Symbiotic microbial have a significant impact on the growth and metabolism of medicinal plants. is a very functionally rich medicinal herb; however, its microbial composition and diversity have been poorly studied.
METHODS
In the present study, the core microbiomes associated with the rhizospheric soil, roots, stems, leaves, and fruits of from six geographic locations were analyzed by a macro-genomics approach.
RESULTS
Alpha and beta diversity analyses showed that the diversity of microbial composition of fruits did not differ significantly among the geographic locations as compared to that in different plant compartments. Principal coordinate analysis showed that the microbial communities of fruits from the different ecological locations were both similar and independent. In all samples, Proteobacteria was the most dominant bacterial phylum, and Ascomycota and Basidiomycota were the most dominant fungal phyla. , and were the marker bacterial populations in rhizospheric soils, roots, stems and leaves, and fruits, respectively, and , and were the marker fungal populations in the rhizospheric soil and roots, stems and leaves, and fruits, respectively. Functional analyses showed a high abundance of the microbiota mainly in biosynthesis.
DISCUSSION
The present study determined the fungal structure of the symbiotic microbiome of , which is crucial for improving the yield and quality of .
PubMed: 38939187
DOI: 10.3389/fmicb.2024.1419943 -
JACS Au Jun 2024The first total synthesis of the repeating units of the -antigens of ATCC 27577, O10, and O19 was achieved via a linear glycosylation strategy. This also represents the...
The first total synthesis of the repeating units of the -antigens of ATCC 27577, O10, and O19 was achieved via a linear glycosylation strategy. This also represents the first synthesis of an oligosaccharide containing an α-linked -acetyl-l-galactosaminuronic acid (l-GalNAcA) unit. All of the glycosyl linkages, including three challenging 1,2--glycosidic bonds of amino sugars, were effectively constructed with high to exclusive stereoselectivity, while orthogonal protection tactics were employed to facilitate regioselective glycosylations and the introduction of a variety of functionalities. An acetyl group migration phenomenon was found during the synthesis of the -acylated repeating unit of the ATCC 27577 antigen. All synthetic targets carried an amino functional group in the linker at the reducing end, thus facilitating further regioselective elaboration and biological studies. The synthetic strategy established here should be useful for the preparation of other similar oligosaccharides.
PubMed: 38938791
DOI: 10.1021/jacsau.4c00321 -
Open Veterinary Journal May 2024This research describes the methodology used for the preparation of selenium nanoparticles from and their administration to lambs for lipid profile checking,...
BACKGROUND
This research describes the methodology used for the preparation of selenium nanoparticles from and their administration to lambs for lipid profile checking, administration of selenium nanoparticles as a medication in lambs results in hypolipidemia.
AIMED
The study aimed to investigate the potential of selenium nanoparticles in improving lipid profiles in lambs.
METHODS
Healthy lambs ( = 10) of similar age and weight were selected for the study. The animals were housed in individual pens with free access to water and a standard diet. The lambs were randomly divided into two groups: the control group ( = 5) and the treatment group ( = 5). The control group received a standard diet, while the treatment group received the same diet and oral administrated with selenium nanoparticles at 0.1 mg/kg body weight. The administration was carried out daily for a period of 8 weeks. Blood samples were collected from the jugular vein of each lamb at the beginning of the study (baseline) and at the end of the 2 weeks treatment period. The samples were collected in vacutainer tubes and allowed to clot. Serum was separated by centrifugation at 3,000 rpm for 10 minutes and stored at -80°C for estimation of lipid profile total cholesterol (TC), triglyceride, high-density lipoprotein (HDL), and low-density lipoprotein (LDL). The serum samples were used for the estimation of lipid profile levels using an enzymatic colorimetric method. The absorbance was measured at 540 nm using a spectrophotometer.
RESULTS
The results showed a significant decrease in serum TC, triglyceride, and very-low-density lipoprotein cholesterol levels after selenium nanoparticle supplementation compared to the control group ( < 0.05), the results indicated a significant increase in serum HDL levels after selenium nanoparticle supplementation compared to the control group ( < 0.05). This indicates that selenium nanoparticle supplementation has a beneficial effect on reducing TC levels in lambs.
CONCLUSION
The conclusion section will summarize the findings of the study and highlight the potential of selenium nanoparticles in improving lipid profiles in lambs. The implications of the study for animal nutrition and health will be discussed, along with the need for further research in this area.
Topics: Animals; Selenium; Male; Nanoparticles; Lipids; Sheep; Pseudomonas aeruginosa; Sheep, Domestic
PubMed: 38938439
DOI: 10.5455/OVJ.2024.v14.i5.10 -
Health Technology Assessment... Jun 2024To limit the use of antimicrobials without disincentivising the development of novel antimicrobials, there is interest in establishing innovative models that fund...
BACKGROUND
To limit the use of antimicrobials without disincentivising the development of novel antimicrobials, there is interest in establishing innovative models that fund antimicrobials based on an evaluation of their value as opposed to the volumes used. The aim of this project was to evaluate the population-level health benefit of cefiderocol in the NHS in England, for the treatment of severe aerobic Gram-negative bacterial infections when used within its licensed indications. The results were used to inform the National Institute for Health and Care Excellence guidance in support of commercial discussions regarding contract value between the manufacturer and NHS England.
METHODS
The health benefit of cefiderocol was first derived for a series of high-value clinical scenarios. These represented uses that were expected to have a significant impact on patients' mortality risks and health-related quality of life. The clinical effectiveness of cefiderocol relative to its comparators was estimated by synthesising evidence on susceptibility of the pathogens of interest to the antimicrobials in a network meta-analysis. Patient-level costs and health outcomes of cefiderocol under various usage scenarios compared with alternative management strategies were quantified using decision modelling. Results were reported as incremental net health effects expressed in quality-adjusted life-years, which were scaled to 20-year population values using infection number forecasts based on data from Public Health England. The outcomes estimated for the high-value clinical scenarios were extrapolated to other expected uses for cefiderocol.
RESULTS
Among isolates with the metallo-beta-lactamase resistance mechanism, the base-case network meta-analysis found that cefiderocol was associated with a lower susceptibility relative to colistin (odds ratio 0.32, 95% credible intervals 0.04 to 2.47), but the result was not statistically significant. The other treatments were also associated with lower susceptibility than colistin, but the results were not statistically significant. In the metallo-beta-lactamase base-case network meta-analysis, cefiderocol was associated with a lower susceptibility relative to colistin (odds ratio 0.44, 95% credible intervals 0.03 to 3.94), but the result was not statistically significant. The other treatments were associated with no susceptibility. In the base case, patient-level benefit of cefiderocol was between 0.02 and 0.15 quality-adjusted life-years, depending on the site of infection, the pathogen and the usage scenario. There was a high degree of uncertainty surrounding the benefits of cefiderocol across all subgroups. There was substantial uncertainty in the number of infections that are suitable for treatment with cefiderocol, so population-level results are presented for a range of scenarios for the current infection numbers, the expected increases in infections over time and rates of emergence of resistance. The population-level benefits varied substantially across the base-case scenarios, from 896 to 3559 quality-adjusted life-years over 20 years.
CONCLUSION
This work has provided quantitative estimates of the value of cefiderocol within its areas of expected usage within the NHS.
LIMITATIONS
Given existing evidence, the estimates of the value of cefiderocol are highly uncertain.
FUTURE WORK
Future evaluations of antimicrobials would benefit from improvements to NHS data linkages; research to support appropriate synthesis of susceptibility studies; and application of routine data and decision modelling to assess enablement value.
STUDY REGISTRATION
No registration of this study was undertaken.
FUNDING
This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment Policy Research Programme (NIHR award ref: NIHR135591), conducted through the Policy Research Unit in Economic Methods of Evaluation in Health and Social Care Interventions, PR-PRU-1217-20401, and is published in full in ; Vol. 28, No. 28. See the NIHR Funding and Awards website for further award information.
Topics: Humans; Cephalosporins; Anti-Bacterial Agents; Quality-Adjusted Life Years; Cost-Benefit Analysis; England; Technology Assessment, Biomedical; Cefiderocol; Gram-Negative Bacterial Infections; State Medicine; Quality of Life
PubMed: 38938145
DOI: 10.3310/YGWR4511