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Scientific Reports Dec 2023Environmental pollution is a global phenomenon and troublesome fact that poses a grave risk to all living entities. Via coupling carbonaceous feedstocks with outstanding...
Environmental pollution is a global phenomenon and troublesome fact that poses a grave risk to all living entities. Via coupling carbonaceous feedstocks with outstanding microbial activity, kinetic experiments were established using the consortium of Proteus mirabilis and Raoultella planticola, biochar-derived sunflower seed husk (SHB) and rice straw (RSB), and their composites, which investigated at 30 °C (150 rpm) to eliminate 700 mg L lead (120 h) and phenol (168 h) from synthetic wastewater. The derived biochars physicochemical properties of were studied. According to adsorption capacity (q), consortium-SHB composites and consortium-RSB composites removed lead completely (70 mg g) within 48 h and 66 h, respectively. Besides, phenol was remediated entirely after 42 h and 48 h by both composite systems (69.90 mg g), respectively, comparing with bacterial consortium only or parent SHB and RSB. Moreover, four kinetic models were studied to describe the bioremediation process. Fractional power and Elovich models could be recommended for describing the adsorption kinetics for lead and phenol removal by the studied biomaterials with high correlation coefficient (R ≥ 0.91 for Pb and ≥ 0.93 for phenol) and lower residual root mean square error (RMSE) and chi-square (X). Overall, bacterial consortium-biochar composites exhibited greater remediation of lead and phenol than the sum of each single bacterial consortium and biochar systems; reflecting synergistic interaction of adsorptive capability of biochar and metabolic performance of bacterial consortium, as denoted by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The current study addressed the successful design of employing functional remediating consortium immobilized on waste biomass-derived biochar as a conducive alternative eco-sorbent and economic platform to detoxify organic and inorganic pollutants.
Topics: Adsorption; Biodegradation, Environmental; Charcoal; Helianthus; Kinetics; Lead; Oryza; Phenol; Phenols; Seeds; Water Pollutants, Chemical; Water Purification
PubMed: 38081934
DOI: 10.1038/s41598-023-49036-x -
Frontiers in Microbiology 2023The purpose of this study was to highlight the clinical and molecular features of 13 strains isolated from clinical environments in Ecuador, and to perform comparative...
PURPOSE
The purpose of this study was to highlight the clinical and molecular features of 13 strains isolated from clinical environments in Ecuador, and to perform comparative genomics with previously published genomes of spp. As is primarily found in environmental, clinical settings, we focused our work on identifying mechanisms of resistance that can provide this bacterium an advantage to establish and persist in hospital environments.
METHODS
We analyzed 13 strains of isolated from patients with healthcare associated infections (HAI) in three hospitals in Quito and one in Santo Domingo de Los Tsáchilas, Ecuador, between November 2017 and April 2018. These isolates were subjected to phenotypic antimicrobial susceptibility testing, end-point polymerase chain reaction (PCR) to detect the presence of carbapenemases and whole-genome sequencing.
RESULTS
Polymerase chain reaction revealed that seven isolates were positive isolates for and one for gene. Of the seven strains that presented the gene, six harbored it on an IncFII plasmid, one was inserted into the bacterial chromosome. The gene was detected in an IncM2/IncR plasmid. From the bioinformatics analysis, nine genomes had the gene , originating from Ecuador. Moreover, all strains contained the ORN-1 gene, which confers resistance for β-lactams, such as penicillins and cephalosporins. Comparative genome analysis of the strains showed that the pangenome of is considered an open pangenome, with 27.77% of core genes, which could be explained by the fact that the antibiotic resistance genes in the ancestral reconstruction are relatively new, suggesting that this genome is constantly incorporating new genes.
CONCLUSION
These results reveal the genome plasticity of , particularly in acquiring antibiotic-resistance genes. The genomic surveillance and infectious control of these uncommon species are important since they may contribute to the burden of antimicrobial resistance and human health.
PubMed: 37692398
DOI: 10.3389/fmicb.2023.1216008 -
Biotechnology Reports (Amsterdam,... Sep 2023High throughput screening approaches can significantly speed up the identification of novel enzymes from natural microbial consortiums. A two-step high throughput...
High throughput screening approaches can significantly speed up the identification of novel enzymes from natural microbial consortiums. A two-step high throughput screening process was proposed and explored to screen lignin-degrading microorganisms. By employing this modified culture enrichment method and screening based on enzyme activity, a total of 82 bacterial and 46 fungal strains were isolated from fifty decayed wood samples (100 liquid cultures) collected from the banks of the Ottawa River in Canada. Among them, ten bacterial and five fungal strains were selected and identified based on their high laccase activities by 16S rDNA and ITS gene sequencing, respectively. The study identified bacterial strains from various genera including , and , along with fungal counterparts including and . Moreover, (AORF21), . (AORF43), (AORF3) and sp. (AORB55) exhibited xylanase and - glucanase activities in addition to laccase production. The proposed approach allowed for the quick identification of promising consortia and enhanced the chance of isolating desired strains based on desired enzyme activities. This method is not limited to lignocellulose and lignin-degrading microorganisms but can be applied to identify novel microbial strains and enzymes from different natural samples.
PubMed: 37583477
DOI: 10.1016/j.btre.2023.e00809 -
Foods (Basel, Switzerland) Oct 2023In this study, we determined and identified the bacterial diversity of different types of artisanal and industrially produced cheese. The antibiotic (erythromycin,...
In this study, we determined and identified the bacterial diversity of different types of artisanal and industrially produced cheese. The antibiotic (erythromycin, chloramphenicol, kanamycin, ampicillin, clindamycin, streptomycin, tetracycline, and gentamicin) and biocide (peracetic acid, sodium hypochlorite, and benzalkonium chloride) resistance of clinically relevant bacteria was determined as follows: , , sp., , , , , , , , sp., , , , , and Also, the effect of the sub-inhibitory concentration of three biocides on antibiotic resistance was determined. The microbiota of evaluated dairy products comprise diverse and heterogeneous groups of bacteria with respect to antibiotic and disinfectant tolerance. The results indicated that resistance was common in the case of ampicillin, chloramphenicol, erythromycin, and streptomycin. sp. SCSSZT2/3, SRGT/1, SAT/1, MTT/5, and SIJ/2 showed resistance to most antibiotics. The tested bacteria showed sensitivity to peracetic acid and a different level of tolerance to benzalkonium chloride and sodium hypochlorite. The inhibition zone diameter of antibiotics against SZT/2, JS11, CSKO2, and GRT/10 was affected only by the sub-inhibitory concentration of peracetic acid.
PubMed: 37959056
DOI: 10.3390/foods12213937 -
Journal of Infection in Developing... Sep 2023The spread of multidrug-resistant bacteria, particularly carbapenem-resistant Gram-negative bacilli (CR-GNB), has become a serious challenge for clinicians due to...
INTRODUCTION
The spread of multidrug-resistant bacteria, particularly carbapenem-resistant Gram-negative bacilli (CR-GNB), has become a serious challenge for clinicians due to limited therapeutic options. The aim of the study was to investigate the prevalence of carbapenemase production among clinical isolates recovered from 352 samples collected in Tebessa hospital, Algeria.
METHODOLOGY
Bacterial isolates were identified by 16S RNA gene sequencing and susceptibility to antibiotics was determined by disk diffusion method. Carbapenem-resistant isolates were screened for carbapenemase production using modified carba Nordmann-Poirel test, modified Hodge test and imipenem-EDTA combined disc test. Extended-spectrum β-lactamases (ESBL) were detected using double-disk synergy test. Molecular characterization of carbapenemases and ESBL genes was performed by polymerase chain reaction (PCR) and sequencing.
RESULTS
A total of 85 Gram-negative bacilli isolates were recovered mainly from urine samples and were identified as: Klebsiella pneumoniae (17.65%), Serratia odorifera (15.29%), Escherichia coli (12.94%), Raoultella ornithinolytica, Enterobacter cloacae (11.76%), Serratia marcescens (10.59%), Morganella morganii (7.06%), Proteus mirabilis (5.88%), Acinetobacter baumannii (4.70%) and Pseudomonas aeruginosa (2.35%). All strains were resistant or intermediate to imipenem and/or ertapenem. ESBL, carbapenemase and metallo-beta-lactamases (MBL) phenotypes were detected in 19 (22.35%), 9 (10.59%) and 2 (2.35%) GNB isolates, respectively. PCR results in nine carbapenemase-producing GNB strains chosen showed the presence of one to four carbapenemase genes (blaGES, blaSME, blaNDM-1, blaVIM, blaGIM, blaSPM, blaOXA-48) in four strains; however, seven strains had at least one ESBL gene (blaTEM-1, blaCTXM-15, blaSHV).
CONCLUSIONS
In this study, we report the first incidence of blaNDM-1 gene in Enterobacter cloacae isolated from urine sample in Algeria.
Topics: Enterobacter cloacae; beta-Lactamases; Bacterial Proteins; Gram-Negative Bacteria; Anti-Bacterial Agents; Carbapenems; Imipenem; Escherichia coli; Microbial Sensitivity Tests
PubMed: 37824354
DOI: 10.3855/jidc.18031 -
The Science of the Total Environment Aug 2023Anthropogenic activities have increased the dispersal of emerging contaminants (ECs), particularly of parabens, causing an escalation of their presence in wastewater...
Anthropogenic activities have increased the dispersal of emerging contaminants (ECs), particularly of parabens, causing an escalation of their presence in wastewater (WW). Current WW technologies do not present satisfactory efficiency or sustainability in removing these contaminants. However, bioremediation with microalgae-based systems is proving to be a relevant technology for WW polishing, and the use of microalgae-bacteria consortia can improve the efficiency of WW treatment. This work aimed to study dual cultures of selected bacteria (Raoultella ornithinolytica, Acidovorax facilis, Acinetobacter calcoaceticus, Leucobacter sp. or Rhodococcus fascians) and the microalga Chlorella vulgaris in microbial growth and WW bioremediation - removal of methylparaben (MetP) and nutrients. The association with the bacteria was antagonistic for C. vulgaris biomass productivity as a result of the decreased growth kinetics in comparison to the axenic microalga. The presence of MetP did not disturb the growth of C. vulgaris under axenic or co-cultured conditions, except when associated with R. fascians, where growth enhancement was observed. The removal of MetP by the microalga was modest (circa 30 %, with a removal rate of 0.0343 mg/L.d), but increased remarkably when the consortia were used (> 50 %, with an average removal rate > 0.0779 mg/L.d), through biodegradation and photodegradation. For nutrient removal, the consortia were found to be less effective than the axenic microalga, except for nitrogen (N) removal by C. vulgaris w/ R. fascians. The overall results propose that C. vulgaris co-cultivation with bacteria can increase MetP removal, while negatively affecting the microalga growth and the consequent reduction of sludge production, highlighting the potential of microalgae-bacteria consortia for the effective polishing of WW contaminated with parabens.
Topics: Chlorella vulgaris; Wastewater; Coculture Techniques; Parabens; Bacteria; Microalgae
PubMed: 37121314
DOI: 10.1016/j.scitotenv.2023.163746 -
Veterinary Sciences Oct 2023The spread of antibiotic resistance genes (ARGs) in the environment exacerbates the contamination of these genes; therefore, the role plants play in the transmission of...
The spread of antibiotic resistance genes (ARGs) in the environment exacerbates the contamination of these genes; therefore, the role plants play in the transmission of resistance genes in the food chain requires further research. Giant pandas consume different bamboo parts at different times, which provides the possibility of investigating how a single food source can affect the variation in the spread of ARGs. In this study, metagenomic analysis and the Comprehensive Antibiotic Resistance Database (CARD) database were used to annotate ARGs and the differences in gut microbiota ARGs during the consumption of bamboo shoots, leaves, and culms by captive giant pandas. These ARGs were then compared to investigate the impact of bamboo part consumption on the spread of ARGs. The results showed that the number of ARGs in the gut microbiota of the subjects was highest during the consumption of bamboo leaves, while the variety of ARGs was highest during the consumption of shoots. Escherichia coli, which poses a higher risk of ARG dissemination, was significantly higher in the leaf group, while , , and were significantly higher in the shoot group. The ARG risk brought by bamboo shoots and leaves may originate from soil and environmental pollution. It is recommended to handle the feces of giant pandas properly and regularly monitor the antimicrobial and virulence genes in their gut microbiota to mitigate the threat of antibiotic resistance.
PubMed: 37999453
DOI: 10.3390/vetsci10110630 -
in a Healthy, Young Person: Rapidly Progressive Sinusitis with Orbital and Intracranial Involvement.European Journal of Case Reports in... 2023is an encapsulated, Gram-negative, nonmotile, rod belonging to the family. Infections involving the gastrointestinal tract and the hepatopancreatobiliary system are...
UNLABELLED
is an encapsulated, Gram-negative, nonmotile, rod belonging to the family. Infections involving the gastrointestinal tract and the hepatopancreatobiliary system are most frequently reported, especially in immunocompromised patients. The authors present an unusual case of acute complicated sinusitis with orbital and intracranial involvement caused by . The infection was rapidly progressive, even though the patient was a healthy, young person without any co-morbidities. The patient's condition improved after antibiotic treatment and multiple ophthalmic and sinus surgeries.
LEARNING POINTS
can cause rapidly progressive infections, even in immunocompetent young individuals. identified in sinusitis can be a true pathogen rather than an innocent bystander.
PubMed: 37789980
DOI: 10.12890/2023_003987 -
Polymers Dec 2023The product of ozonolysis, glycero-(9,10-trioxolane)-trioleate (ozonide of oleic acid triglyceride, [OTOA]), was incorporated into polylactic acid/polycaprolactone...
The product of ozonolysis, glycero-(9,10-trioxolane)-trioleate (ozonide of oleic acid triglyceride, [OTOA]), was incorporated into polylactic acid/polycaprolactone (PLA/PCL) blend films in the amount of 1, 5, 10, 20, 30 and 40% /. The morphological, mechanical, thermal and antibacterial properties of the biodegradable PLA/PCL films after the OTOA addition were studied. According to DSC and XRD data, the degree of crystallinity of the PLA/PCL + OTOA films showed a general decreasing trend with an increase in OTOA content. Thus, a significant decrease from 34.0% for the reference PLA/PCL film to 15.7% for the PLA/PCL + 40% OTOA film was established using DSC. Observed results could be explained by the plasticizing effect of OTOA. On the other hand, the PLA/PCL film with 20% OTOA does not follow this trend, showing an increase in crystallinity both via DSC (20.3%) and XRD (34.6%). OTOA molecules, acting as a plasticizer, reduce the entropic barrier for nuclei formation, leading to large number of PLA spherulites in the plasticized PLA/PCL matrix. In addition, OTOA molecules could decrease the local melt viscosity at the vicinity of the growing lamellae, leading to faster crystal growth. Morphological analysis showed that the structure of the films with an OTOA concentration above 20% drastically changed. Specifically, an interface between the PLA/PCL matrix and OTOA was formed, thereby forming a capsule with the embedded antibacterial agent. The moisture permeability of the resulting PLA/PCL + OTOA films decreased due to the formation of uniformly distributed hydrophobic amorphous zones that prevented water penetration. This architecture affects the tensile characteristics of the films: strength decreases to 5.6 MPa, elastic modulus E by 40%. The behavior of film elasticity is associated with the redistribution of amorphous regions in the matrix. Additionally, PLA/PCL + OTOA films with 20, 30 and 40% of OTOA showed good antibacterial properties on , () and , making the developed films potentially promising materials for wound-dressing applications.
PubMed: 38201793
DOI: 10.3390/polym16010128 -
Zhonghua Yu Fang Yi Xue Za Zhi [Chinese... Dec 2023To explore the drug resistance mechanism and gene structure characteristics of a carbapenemase-producing novel incompatibility group plasmid pNY2385-KPC from . A...
To explore the drug resistance mechanism and gene structure characteristics of a carbapenemase-producing novel incompatibility group plasmid pNY2385-KPC from . A multi-drug resistant strain was obtained from urine samples of patients with fever in the emergency ward of Li Huili Hospital, Ningbo Medical Center. Bacterial species was preliminary identified and finally confirmed by 16S rRNA gene amplification and the average nucleotide identity alignment, respectively. The minimum inhibitory concentrations of the antimicrobial agents were determined by VITEK 2 Compact System. The complete genome sequence was obtained by "third-generation" sequencing methods, and then detailed annotation of gene function and comparative genomic analysis of plasmid structure were carried out by BLASTP/BLASTN, RefSeq, ConservedDomains, ResFinder, Isfinder, etc. The pNY2385-KPC carried by NY2385 belonged a novel incompatibility group, and contained and conjugative transfer (type Ⅳ secretory system, T4SS) genes, which could induce conjugative transfer. A total of 15 plasmids of the same type as pNY2385-KPC were retrieved by NCBI, which were from , and the rest were from , , , , and other bacteria, and were broad-host-range plasmids. The sequence comparative analysis of all 6 of the novel plasmid from showed that the structure of the novel plasmid had certain conserved property, with Tn variant structure carrying , and plasmid pCF1807-3 had both and . The pNY2385-KPC type plasmids in carried resistance gene, which were divided into two subtypes: single replicator and / complex replicator, belonging to broad-host-range plasmids. And as a mobile genetic element, the plasmids promote the spread of .
Topics: Humans; Citrobacter freundii; RNA, Ribosomal, 16S; Emergency Service, Hospital; Escherichia coli; Genomics
PubMed: 38186165
DOI: 10.3760/cma.j.cn112150-20230530-00419