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Environmental Pollution (Barking, Essex... Jun 2024Triclocarban (TCC), an antibacterial agent commonly used in personal care products, is one of the top ten contaminants of emerging concern in various environmental...
Triclocarban (TCC), an antibacterial agent commonly used in personal care products, is one of the top ten contaminants of emerging concern in various environmental media, including soil and contaminated water in vadose zone. This study aimed to investigate TCC-contaminated water remediation using biochar-immobilized bacterial cells. Pseudomonas fluorescens strain MC46 (MC46), an efficient TCC-degrading isolate, was chosen, whereas agro-industrial carbonized waste as biochar was directly used as a sustainable cell immobilization carrier. According to the long-term TCC removal performance results (160 d), the biochar-immobilized cells consistently exhibited high TCC removal efficiencies (84-97%), whereas the free MC46 removed TCC for 76-94%. At 100 days, the detachment of the MC46 cells from the immobilized cell column was observed. The micro-Fourier-transform infrared spectroscopy results indicated that extracellular polymeric substance (EPS) was produced, but polysaccharide and protein fractions were washed out of the column. The lipid fraction of EPS adhered to the biochar, promoting TCC sorption for long-term treatment. The shortening of MC46 cells improved the tolerance of TCC toxicity. The TCC-contaminated water was successfully detoxified by the biochar-immobilized MC46 cells. Overall, the waste-derived biochar-immobilized cell system proposed in this study for the removal of emerging contaminants, including TCC, is efficient, economical, and aligned with the sustainable development concept of value-added utilization of waste.
PubMed: 38942273
DOI: 10.1016/j.envpol.2024.124456 -
International Journal of Pharmaceutics Jun 2024This paper focuses on the preparation and characterization of antibacterial alginate microparticles containing silver@hydroxyapatite functionalized calcium carbonate...
This paper focuses on the preparation and characterization of antibacterial alginate microparticles containing silver@hydroxyapatite functionalized calcium carbonate composites for tissue engineering. Microparticles were prepared by cross-linking a silver@composite sodium alginate dispersion with CaCl. This method showed a very good silver efficiency loading and the presence of silver chloride nanoparticles was detected. Silver free microparticles, containing hydroxyapatite functionalized calcium carbonates and neat alginate microparticles were prepared as well. All microparticles were characterized for water absorption and for in vitro bioactivity by immersion in simulated body fluid (SBF). Finally, antimicrobial and antibiofilm activities as well as cytotoxicity were evaluated. Microparticles containing silver@composites exhibited good antimicrobial and antibiofilm activities against Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa and Candida albicans, but exerted a certain cytotoxicity against the tested cell models (fibroblasts and osteoblasts). Microparticles containing hydroxyapatite functionalized calcium carbonates were found to be always less cytotoxic, also in comparison to neat alginate microparticles, proving that the presence of the inorganic matrices exerts a protective effect on microparticle cytotoxicity.
PubMed: 38942183
DOI: 10.1016/j.ijpharm.2024.124393 -
Spectrochimica Acta. Part A, Molecular... Jun 2024The impact of microbial infections is increasing over time, and it is one of the major reasons for death in both developed and developing countries. colistin is...
The impact of microbial infections is increasing over time, and it is one of the major reasons for death in both developed and developing countries. colistin is considered as the antibiotic of last choice for infections brought by major multidrug-resistant (MDR), gram-negative bacteria such as Enterobacter species, Acinetobacter species, and Pseudomonas aeruginosa. Existing approaches to diagnose these resistant species are relatively slow and take up to 2 to 3 days. In this work, we propose a novel interdisciplinary method based on Raman spectroscopy and heavy water to identify colistin-resistant microbes. Our hypothesis is based on the fact that resistant bacteria will be metabolically active in the culture medium containing antibiotics and heavy water, and these bacteria will take up deuterium instead of hydrogen to newly synthesized lipids and proteins. This effect will generate a 'C - D' bond-specific Raman spectral marker. Successful identification of this band in the spectral profile can confirm the presence of colistin-resistant bacteria. We have validated the efficacy of this approach in identifying colistin-resistant bacteria spiked in artificial urine and have compared sensitivity at different bacterial concentrations. Overall findings suggest that heavy water can potentially serve as a suitable Raman probe for identifying metabolically active colistin-resistant bacteria via urine under clinically implementable time and can be used in clinical settings after validation.
PubMed: 38941753
DOI: 10.1016/j.saa.2024.124723 -
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