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Journal of Microbiological Methods Jun 2024Current methods for plasmid-mediated AmpC β-lactamase (pAmpC) detection in routine microbiological laboratories are based on various phenotypic tests.... (Comparative Study)
Comparative Study
Current methods for plasmid-mediated AmpC β-lactamase (pAmpC) detection in routine microbiological laboratories are based on various phenotypic tests. Eazyplex®SuperBug AmpC assay is a molecular assay based on isothermal amplification for rapid detection of the most common pAmpC types from bacterial culture: CMY-2 group, DHA, ACC and MOX. Our aim was to evaluate the diagnostic performance of this assay. The assay was evaluated on 64 clinical isolates of Enterobacterales without chromosomal inducible AmpC, and with phenotypically confirmed AmpC production. The results were confirmed, and isolates further characterized by whole-genome sequencing (WGS). eazyplex®SuperBug AmpC assay correctly detected the two most common pAmpC types CMY-2 group (16/16) and DHA (19/19). Detection of ACC and MOX could not be evaluated on our set of isolates since there was only one isolate harbouring ACC and none with MOX. pAmpC encoding genes could be detected in only eight of 36 investigated Escherichia coli isolates. The remaining 28 E. coli isolates harboured previously described mutations in the bla promoter, leading to the overexpression of chromosomally encoded E. coli specific AmpC β-lactamase. All results were 100% concordant with the results of WGS. eazyplex®SuperBug AmpC assay enabled rapid and reliable detection of pAmpC-encoding genes in Enterobacterales like Klebsiella spp. and Proteus spp. and the distinction between plasmid-mediated and chromosomally encoded AmpC in E. coli.
Topics: beta-Lactamases; Plasmids; Whole Genome Sequencing; Bacterial Proteins; Humans; Escherichia coli; Enterobacteriaceae; Anti-Bacterial Agents; Microbial Sensitivity Tests; Nucleic Acid Amplification Techniques
PubMed: 38642781
DOI: 10.1016/j.mimet.2024.106938 -
Journal of Infection in Developing... Mar 2024The spread of Carbapenemase-producing Enterobacterales (CPEs) has become a significant concern in Algeria, with limited data available on their presence in community...
INTRODUCTION
The spread of Carbapenemase-producing Enterobacterales (CPEs) has become a significant concern in Algeria, with limited data available on their presence in community settings. This research investigated the resistance mechanisms of carbapenem-resistant Enterobacterales (CREs) collected from hospitals and the community in Skikda city, Algeria, between December 2020 and June 2022.
METHODOLOGY
The study collected Enterobacterales strains resistant to ertapenem from inpatient and outpatient populations. An automated system was used for identification and antibiotic susceptibility testing. β-lactamase production was evaluated through phenotypic tests and confirmed by standard PCR. Lastly, the carbapenemase genes were sequenced using the Sanger method.
RESULTS
17 CRE were isolated, with 9 from inpatients and 8 from outpatients. These isolates belonged to four species: Klebsiella pneumoniae (n = 8), Escherichia coli (n = 6), Enterobacter cloacae (n = 1), and Proteus mirabilis (n = 1). Of 15 CPEs, 11 were extended-spectrum β-lactamases (ESBLs) positive, 5 were plasmid-mediated cephalosporinase (AmpC) positive, and 1 harbored all three β-lactamases. All metallo-β-lactamase-producing strains carried the New Delhi metallo-beta-lactamase gene (blaNDM), including 5 NDM-1 and 7 NDM-5 variants. The presence of blaOXA-48 and blaOXA-244 was observed in one outpatient strain each. NDM was associated with Cefotaximase Munich (CTX-M) ESBL in 8 isolates, while Cephamycinase (CMY) was detected in 3 NDM-5-producing E. coli.
CONCLUSIONS
This research highlights the rising prevalence of carbapenemases NDM-1 and NDM-5 among inpatients and outpatients and supports the notion that OXA-48 is becoming increasingly widespread beyond Algerian hospitals.
Topics: Humans; Escherichia coli; Outpatients; Inpatients; Anti-Bacterial Agents; Algeria; Prevalence; beta-Lactamases; Bacterial Proteins; Klebsiella pneumoniae; Carbapenems; Microbial Sensitivity Tests
PubMed: 38635605
DOI: 10.3855/jidc.18263 -
Biotechnologia 2024The ever-increasing demand for wildlife-derived raw or processed meat commonly known as bushmeat, has been identified as one of the critical factors driving the...
The ever-increasing demand for wildlife-derived raw or processed meat commonly known as bushmeat, has been identified as one of the critical factors driving the emergence of infectious diseases. This study focused on examining the bacterial community composition of smoked and fermented bushmeats, specifically grasscutter, rat, rabbit, and mona monkey. The analysis involved exploring 16Sr RNA amplicon sequences isolated from bushmeat using QIIME2. Microbiome profiles and their correlation with proximate components (PLS regression) were computed in STAMP and XLSTAT, respectively. Results indicate the predominance of (70.9%), (18.58%), and (9.12%) in bushmeat samples at the phylum level. , , , and constituted the core microbiomes in bushmeat samples, ranked in descending order. Notably, significant differences were observed between the bacterial communities of bushmeat obtained from omnivores and herbivores (rat and mona monkey, and grasscutter and mona monkey), as well as those with similar feeding habits (rat and monkey, and grasscutter and rabbit) at the family and genus levels. Each type of bushmeat possessed unique microbial diversity, with some proximate components such as fat in rat samples correlating with , while proteins in Mona monkey correlated with and , respectively. The study underscores public health concerns and highlights probiotic benefits, as bushmeat samples contained both pathogenic and beneficial bacteria. Therefore, future research efforts could focus on improving bushmeat quality.
PubMed: 38633890
DOI: 10.5114/bta.2024.135637 -
The Science of the Total Environment Jun 2024Microplastics (MP) have become a well-known and widely investigated environmental pollutant. Despite the huge amount of new studies investigating the potential threat...
Microplastics (MP) have become a well-known and widely investigated environmental pollutant. Despite the huge amount of new studies investigating the potential threat posed by MP, the possible uptake and trophic transfer in lower trophic levels of freshwater ecosystems remains understudied. This study aims to investigate the internalization and potential trophic transfer of fluorescent polystyrene (PS) beads (0.5 μm, 3.6 × 10 particles/mL; 6 μm, 2.1 × 10 particles/mL) and fragments (<30 μm, 5 × 10 particles/mL) in three unicellular eukaryotes. This study focuses on the size-dependent uptake of MP by two freshwater Ciliophora, Tetrahymena pyriformis, Paramecium caudatum and one Amoebozoa, Amoeba proteus, serving also as predator for experiments on potential trophic transfer. Size-dependent uptake of MP in all three unicellular eukaryotes was shown. P. caudatum is able to take up MP fragments up to 27.7 μm, while T. pyriformis ingests particles up to 10 μm. In A. proteus, small MP (PS and PS) were taken up via pinocytosis and were detected in the cytoplasm for up to 14 days after exposure. Large PS-MP (PS) were detected in A. proteus only after predation on MP-fed Ciliophora. These results indicate that A. proteus ingests larger MP via predation on Ciliophora (PS), which would not be taken up otherwise. This study shows trophic transfer of MP at the base of the aquatic food web and serves as basis to study the impact of MP in freshwater ecosystems.
Topics: Microplastics; Water Pollutants, Chemical; Food Chain; Polystyrenes; Fresh Water; Environmental Monitoring; Tetrahymena pyriformis; Amoeba; Paramecium caudatum; Particle Size
PubMed: 38621530
DOI: 10.1016/j.scitotenv.2024.172470 -
International Wound Journal Apr 2024Multidrug-resistant (MDR) bacterial infections have become increasingly common in recent years due to the increased prevalence of diabetic foot ulcers (DFUs). We carried... (Meta-Analysis)
Meta-Analysis
Multidrug-resistant (MDR) bacterial infections have become increasingly common in recent years due to the increased prevalence of diabetic foot ulcers (DFUs). We carried out a meta-analysis aimed at investigating the prevalence of MDR bacteria isolated from DFUs and analysing the risk factors for MDR bacterial infection in patients with DFUs. The PubMed/Medline, Web of Science, Embase, Cochrane Library, Ovid, Scopus, and ProQuest databases were searched for studies published up to November 2023 on the clinical outcomes of MDR bacteria in DFUs. The main outcome was the prevalence of MDR bacteria in DFUs. A total of 21 studies were included, representing 4885 patients from which 2633 MDR bacterial isolates were obtained. The prevalence of MDR bacteria in DFUs was 50.86% (95% confidence interval (CI): 41.92%-59.78%). The prevalence of MDR gram-positive bacteria (GPB) in DFUs was 19.81% (95% CI: 14.35%-25.91%), and the prevalence of MDR gram-negative bacteria (GNB) in DFUs was 32.84% (95% CI: 26.40%-39.62%). MDR Staphylococcus aureus (12.13% (95% CI: 8.79%-15.91%)) and MDR Enterococcus spp. (3.33% (95% CI: 1.92%-5.07%)) were the main MDR-GPB in DFUs. MDR Escherichia coli, MDR Pseudomonas aeruginosa, MDR Enterobacter spp., MDR Klebsiella pneumoniae, and MDR Proteus mirabilis were the main MDR-GNB in DFUs. The prevalence rates were 6.93% (95% CI: 5.15%-8.95%), 6.01% (95% CI: 4.03%-8.33%), 3.59% (95% CI: 0.42%-9.30%), 3.50% (95% CI: 2.31%-4.91%), and 3.27% (95% CI: 1.74%-5.21%), respectively. The clinical variables of diabetic foot ulcer patients infected with MDR bacteria and non-MDR bacteria in the included studies were analysed. The results showed that peripheral vascular disease, peripheral neuropathy, nephropathy, osteomyelitis, Wagner's grade, previous hospitalization and previous use of antibacterial drugs were significantly different between the MDR bacterial group and the non-MDR bacterial group. We concluded that there is a high prevalence of MDR bacterial infections in DFUs. The prevalence of MDR-GNB was greater than that of MDR-GPB in DFUs. MDR S. aureus was the main MDR-GPB in DFUs, and MDR E. coli was the main MDR-GNB in DFUs. Our study also indicated that peripheral vascular disease, peripheral neuropathy, nephropathy, osteomyelitis, Wagner's grade, previous hospitalization, and previous use of antibacterial drugs were associated with MDR bacterial infections in patients with DFUs.
Topics: Humans; Diabetic Foot; Escherichia coli; Prevalence; Staphylococcus aureus; Anti-Bacterial Agents; Osteomyelitis; Peripheral Vascular Diseases; Bacterial Infections; Diabetes Mellitus
PubMed: 38619084
DOI: 10.1111/iwj.14864 -
Scientific Reports Apr 2024Heavy metal accumulation increases rapidly in the environment due to anthropogenic activities and industrialization. The leather and surgical industry produces many...
Heavy metal accumulation increases rapidly in the environment due to anthropogenic activities and industrialization. The leather and surgical industry produces many contaminants containing heavy metals. Cadmium, a prominent contaminant, is linked to severe health risks, notably kidney and liver damage, especially among individuals exposed to contaminated wastewater. This study aims to leverage the natural cadmium resistance mechanisms in bacteria for bioaccumulation purposes. The industrial wastewater samples, characterized by an alarming cadmium concentration of 29.6 ppm, 52 ppm, and 76.4 ppm-far exceeding the recommended limit of 0.003 ppm-were subjected to screening for cadmium-resistant bacteria using cadmium-supplemented media with CdCl. 16S rRNA characterization identified Vibrio cholerae and Proteus mirabilis as cadmium-resistant bacteria in the collected samples. Subsequently, the cadmium resistance-associated cadA gene was successfully amplified in Vibrio species and Proteus mirabilis, revealing a product size of 623 bp. Further analysis of the identified bacteria included the examination of virulent genes, specifically the tcpA gene (472 bp) associated with cholera and the UreC gene (317 bp) linked to urinary tract infections. To enhance the bioaccumulation of cadmium, the study proposes the potential suppression of virulent gene expression through in-silico gene-editing tools such as CRISPR-Cas9. A total of 27 gRNAs were generated for UreC, with five selected for expression. Similarly, 42 gRNA sequences were generated for tcpA, with eight chosen for expression analysis. The selected gRNAs were integrated into the lentiCRISPR v2 expression vector. This strategic approach aims to facilitate precise gene editing of disease-causing genes (tcpA and UreC) within the bacterial genome. In conclusion, this study underscores the potential utility of Vibrio species and Proteus mirabilis as effective candidates for the removal of cadmium from industrial wastewater, offering insights for future environmental remediation strategies.
Topics: Humans; Cholera; Proteus mirabilis; Cadmium; CRISPR-Cas Systems; RNA, Ribosomal, 16S; Wastewater; RNA, Guide, CRISPR-Cas Systems; Vibrio; Urinary Tract Infections
PubMed: 38609487
DOI: 10.1038/s41598-024-59340-9 -
Metallomics : Integrated Biometal... May 2024Taking into account that in recent decades there has been an increase in the incidence of urinary stones, especially in highly developed countries, from a wide range of...
Taking into account that in recent decades there has been an increase in the incidence of urinary stones, especially in highly developed countries, from a wide range of potentially harmful substances commonly available in such countries, we chose zinc for the research presented in this article, which is classified by some sources as a heavy metal. In this article, we present the results of research on the influence of Zn2+ ion on the nucleation and growth of struvite crystals-the main component of infection urinary stones. The tests were carried out in an artificial urine environment with and without the presence of Proteus mirabilis bacteria. In the latter case, the activity of bacterial urease was simulated chemically, by systematic addition of an aqueous ammonia solution. The obtained results indicate that Zn2+ ions compete with Mg2+ ions, which leads to the gradual replacement of Mg2+ ions in the struvite crystal lattice with Zn2+ ions to some extent. This means co-precipitation of Mg-struvite (MgNH4PO4·6H2O) and Znx-struvite (Mg1-xZnxNH4PO4·6H2O). Speciation analysis of chemical complexes showed that Znx-struvite precipitates at slightly lower pH values than Mg-struvite. This means that Zn2+ ions shift the nucleation point of crystalline solids towards a lower pH. Additionally, the conducted research shows that Zn2+ ions, in the range of tested concentrations, do not have a toxic effect on bacteria; on the contrary, it has a positive effect on cellular metabolism, enabling bacteria to develop better. It means that Zn2+ ions in artificial urine, in vitro, slightly increase the risk of developing infection urinary stones.
Topics: Struvite; Zinc; Urinary Calculi; Proteus mirabilis; Humans; Phosphates; Ions; Magnesium Compounds; Crystallization
PubMed: 38599629
DOI: 10.1093/mtomcs/mfae017 -
Molecular Therapy. Oncology Mar 2024Cancer immunotherapy based on bioengineering of bacteria can effectively increase anticancer immune responses. However, few studies have investigated the antitumor...
Cancer immunotherapy based on bioengineering of bacteria can effectively increase anticancer immune responses. However, few studies have investigated the antitumor potential of engineering . Here, we genetically engineered to overexpress flagellin B (FlaB) protein in a murine CT26 tumor model. We found that a large number of FlaB-expressing colonized tumor tissues, enhanced T cell infiltration and secretion of cytokines and cytotoxic proteins in tumors, and significantly restrained tumor growth. Our results also showed that programmed death ligand 1 (PD-L1) expression in tumor-infiltrating immune cells was elevated after treatment with FlaB-expressing . In addition, combination therapy with FlaB-expressing and PD-L1 blockade synergistically improved antitumor efficacy by enhancing infiltration of CD8 cells. Furthermore, serum liver biochemical indices of mice increased in the short term in both the and the FlaB-expressing treatment groups but gradually recovered in the later stage of treatment so that FlaB protein expression did not increase the toxicity of . Taken together, our results suggest that could serve as an engineered bacterium for bacterium-based cancer immunotherapy.
PubMed: 38596299
DOI: 10.1016/j.omton.2024.200770 -
Veterinary Research Apr 2024Proteus mirabilis is a commensal bacterium dwelling in the gastrointestinal (GI) tract of humans and animals. Although New Delhi metallo-β-lactamase 1 (NDM-1) producing...
Proteus mirabilis is a commensal bacterium dwelling in the gastrointestinal (GI) tract of humans and animals. Although New Delhi metallo-β-lactamase 1 (NDM-1) producing P. mirabilis is emerging as a threat, its epidemiology in our society remains largely unknown. LHPm1, the first P. mirabilis isolate harboring NDM-1, was detected from a companion dog that resides with a human owner. The whole-genome study revealed 20 different antimicrobial resistance (AMR) genes against various classes of antimicrobial agents, which corresponded to the MIC results. Genomic regions, including MDR genes, were identified with multiple variations and visualized in a comparative manner. In the whole-genome epidemiological analysis, multiple phylogroups were identified, revealing the genetic relationship of LHPm1 with other P. mirabilis strains carrying various AMR genes. These genetic findings offer comprehensive insights into NDM-1-producing P. mirabilis, underscoring the need for urgent control measures and surveillance programs using a "one health approach".
Topics: Dogs; Humans; Animals; Anti-Bacterial Agents; Proteus mirabilis; Pets; Proteus Infections; Drug Resistance, Multiple, Bacterial; Genomics; Republic of Korea; Microbial Sensitivity Tests; Plasmids; Dog Diseases
PubMed: 38594755
DOI: 10.1186/s13567-024-01306-w -
Scientific Reports Apr 2024Although giant fennel is recognized as a "superfood" rich in phytochemicals with antioxidant activity, research into the antibacterial properties of its fruits has been...
Comprehensive analysis of different solvent extracts of Ferula communis L. fruit reveals phenolic compounds and their biological properties via in vitro and in silico assays.
Although giant fennel is recognized as a "superfood" rich in phytochemicals with antioxidant activity, research into the antibacterial properties of its fruits has been relatively limited, compared to studies involving the root and aerial parts of the plant. In this study, seven solvents-acetone, methanol, ethanol, ethyl acetate, chloroform, water, and hexane-were used to extract the chemical constituents of the fruit of giant fennel (Ferula communis), a species of flowering plant in the carrot family Apiaceae. Specific attributes of these extracts were investigated using in silico simulations and in vitro bioassays. High-performance liquid chromatography equipped with a diode-array detector (HPLC-DAD) identified 15 compounds in giant fennel extract, with p-coumaric acid, 3-hydroxybenzoic acid, sinapic acid, and syringic acid being dominant. Among the solvents tested, ethanol demonstrated superior antioxidant activity and phenolic and flavonoid contents. F. communis extracts showed advanced inhibition of gram-negative pathogens (Escherichia coli and Proteus mirabilis) and variable antifungal activity against tested strains. Molecular docking simulations assessed the antioxidative, antibacterial, and antifungal properties of F. communis, facilitating innovative therapeutic development through predicted compound-protein interactions. In conclusion, the results validate the ethnomedicinal use and potential of F. communis. This highlights its significance in natural product research and ethnopharmacology.
Topics: Solvents; Fruit; Ferula; Antifungal Agents; Plant Extracts; Antioxidants; Molecular Docking Simulation; Anti-Bacterial Agents; Ethanol
PubMed: 38594363
DOI: 10.1038/s41598-024-59087-3