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Environmental Research Nov 2023The widespread presence of oxytetracycline (OTC) in aquatic ecosystems poses both health risks and ecological concerns. The present study revealed the beneficial role of...
The widespread presence of oxytetracycline (OTC) in aquatic ecosystems poses both health risks and ecological concerns. The present study revealed the beneficial role of hydrogen peroxide (HO)-pretreated biochar (BC) derived from agricultural hardwood waste in an activated sludge (AS) bioprocess. The BC addition significantly enhanced the removal and detoxification of OTC and its byproducts. BC was initially modified using HO to improve its OTC adsorption. Two AS reactors were then established, one with HO-modified BC and one without, and both were exposed to OTC. The BC-added reactor exhibited significantly higher OTC removal rates during both the start-up (0.97 d) and steady-state (0.98 d) phases than the reactor without BC (0.54 d and 0.83 d, respectively). Two novel transformation pathways for OTC were proposed, with four byproducts originating from OTC identified, some of which were found to be more toxic than OTC itself. The BC-added reactor had significantly higher system functioning in terms of its heterotrophic activity and the reduction of the toxicity of OTC and its byproducts, as illustrated by structure-based toxicity simulations, antimicrobial susceptibility experiments, analytical chemistry, and bioinformatics analysis. Bioinformatics revealed two novel bacterial populations closely related to the known OTC-degrader Pandoraea. The ecophysiology and selective enrichment of these populations suggested their role in the enzymatic breakdown and detoxification of OTC (e.g., via demethylation and hydrogenation). Overall, the present study highlighted the beneficial role of HO-modified BC in combination with the AS microbiome in terms of enhancing treatment performance and resilience, reducing the toxicological disruption to biodiversity, and detoxifying micropollutants.
PubMed: 37543124
DOI: 10.1016/j.envres.2023.116832 -
Cancer Research and Treatment Jan 2024Triple-negative breast cancer (TNBC) is a breast cancer subtype that has poor prognosis and exhibits a unique tumor microenvironment. Analysis of the tumor microbiome...
PURPOSE
Triple-negative breast cancer (TNBC) is a breast cancer subtype that has poor prognosis and exhibits a unique tumor microenvironment. Analysis of the tumor microbiome has indicated a relationship between the tumor microenvironment and treatment response. Therefore, we attempted to reveal the role of the tumor microbiome in patients with TNBC receiving neoadjuvant chemotherapy.
MATERIALS AND METHODS
We collected TNBC patient RNA-sequencing samples from the Gene Expression Omnibus and extracted microbiome count data. Differential and relative abundance were estimated with linear discriminant analysis effect size. We calculated the immune cell fraction with CIBERSORTx and conducted survival analysis using the Cancer Genome Atlas patient data. Correlations between the microbiome and immune cell compositions were analyzed and a prediction model was constructed to estimate drug response.
RESULTS
Among the pathological complete response group (pCR), the beta diversity varied considerably; consequently, 20 genera and 24 species were observed to express a significant differential and relative abundance. Pandoraea pulmonicola and Brucella melitensis were found to be important features in determining drug response. In correlation analysis, Geosporobacter ferrireducens, Streptococcus sanguinis, and resting natural killer cells were the most correlated factors in the pCR, whereas Nitrosospira briensis, Plantactinospora sp. BC1, and regulatory T cells were key features in the residual disease group.
CONCLUSION
Our study demonstrated that the microbiome analysis of tumor tissue can predict chemotherapy response of patients with TNBC. Further, the immunological tumor microenvironment may be impacted by the tumor microbiome, thereby affecting the corresponding survival and treatment response.
Topics: Humans; Triple Negative Breast Neoplasms; Neoadjuvant Therapy; Tumor Microenvironment; Antineoplastic Combined Chemotherapy Protocols; Prognosis
PubMed: 37499695
DOI: 10.4143/crt.2023.330 -
Chemosphere Sep 2023Bioremediation has tremendous potential to mitigate the serious threats posed by polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs). In the present study,...
Bioremediation has tremendous potential to mitigate the serious threats posed by polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs). In the present study, nine bacterial-fungal consortia were progressively acclimated under different culture conditions. Among them, a microbial consortium 1, originating from activated sludge and copper mine sludge microorganisms, was developed through the acclimation of a multi-substrate intermediate (catechol)-target contaminant (Cd, phenanthrene (PHE)). Consortium 1 exhibited the best PHE degradation, with an efficiency of 95.6% after 7 d of inoculation, and its tolerance concentration for Cd was up to 1800 mg/L within 48 h. Bacteria Pandoraea and Burkholderia-Caballeronia-Paraburkholderia, as well as fungi Ascomycota and Basidiomycota predominated in the consortium 1. Furthermore, a biochar-loaded consortium was constructed to better cope with the co-contamination behavior, which exhibited excellent adaptation to Cd ranging of 50-200 mg/L. Immobilized consortium efficiently degraded 92.02-97.77% of 50 mg/L PHE within 7 d while removing 93.67-99.04% of Cd. In remediation of co-pollution, immobilization technology improved the bioavailability of PHE and dehydrogenase activity of the consortium to enhance PHE degradation, and the phthalic acid pathway was the main metabolic pathway. As for Cd removal, oxygen-containing functional groups (-OH, C=O, and C-O) of biochar or microbial cell walls and EPS components, fulvic acid and aromatic proteins, participated through chemical complexation and precipitation. Furthermore, immobilization led to more active consortium metabolic activity during the reaction, and the community structure developed in a more favorable direction. The dominant species were Proteobacteria, Bacteroidota, and Fusarium, and the predictive expression of functional genes corresponding to key enzymes was elevated. This study provides a basis for combining biochar and acclimated bacterial-fungal consortia for co-contaminated site remediation.
Topics: Cadmium; Sewage; Soil Pollutants; Phenanthrenes; Polycyclic Aromatic Hydrocarbons; Bacteria; Biodegradation, Environmental; Acclimatization; Soil
PubMed: 37327827
DOI: 10.1016/j.chemosphere.2023.139234 -
International Microbiology : the... Feb 2024Polymyxin B is considered a last-line therapeutic option against multidrug-resistant gram-negative bacteria, especially in COVID-19 coinfections or other serious...
BACKGROUND
Polymyxin B is considered a last-line therapeutic option against multidrug-resistant gram-negative bacteria, especially in COVID-19 coinfections or other serious infections. However, the risk of antimicrobial resistance and its spread to the environment should be brought to the forefront.
METHODS
Pandoraea pnomenusa M202 was isolated under selection with 8 mg/L polymyxin B from hospital sewage and then was sequenced by the PacBio RS II and Illumina HiSeq 4000 platforms. Mating experiments were performed to evaluate the transfer of the major facilitator superfamily (MFS) transporter in genomic islands (GIs) to Escherichia coli 25DN. The recombinant E. coli strain Mrc-3 harboring MFS transporter encoding gene FKQ53_RS21695 was also constructed. The influence of efflux pump inhibitors (EPIs) on MICs was determined. The mechanism of polymyxin B excretion mediated by FKQ53_RS21695 was investigated by Discovery Studio 2.0 based on homology modeling.
RESULTS
The MIC of polymyxin B for the multidrug-resistant bacterial strain P. pnomenusa M202, isolated from hospital sewage, was 96 mg/L. GI-M202a, harboring an MFS transporter-encoding gene and conjugative transfer protein-encoding genes of the type IV secretion system, was identified in P. pnomenusa M202. The mating experiment between M202 and E. coli 25DN reflected the transferability of polymyxin B resistance via GI-M202a. EPI and heterogeneous expression assays also suggested that the MFS transporter gene FKQ53_RS21695 in GI-M202a was responsible for polymyxin B resistance. Molecular docking revealed that the polymyxin B fatty acyl group inserts into the hydrophobic region of the transmembrane core with Pi-alkyl and unfavorable bump interactions, and then polymyxin B rotates around Tyr43 to externally display the peptide group during the efflux process, accompanied by an inward-to-outward conformational change in the MFS transporter. Additionally, verapamil and CCCP exhibited significant inhibition via competition for binding sites.
CONCLUSIONS
These findings demonstrated that GI-M202a along with the MFS transporter FKQ53_RS21695 in P. pnomenusa M202 could mediate the transmission of polymyxin B resistance.
Topics: Polymyxin B; Escherichia coli; Genomic Islands; Molecular Docking Simulation; Sewage; Membrane Transport Proteins; Anti-Bacterial Agents; Microbial Sensitivity Tests; Burkholderiaceae
PubMed: 37316617
DOI: 10.1007/s10123-023-00384-8 -
Journal of Hazardous Materials Sep 2023The treatment of chlorinated volatile organic compounds faces challenges of secondary pollution and less-efficiency due to the substitution of chlorine. Microbial fuel...
The treatment of chlorinated volatile organic compounds faces challenges of secondary pollution and less-efficiency due to the substitution of chlorine. Microbial fuel cells (MFCs) provide a promising opportunity for its abatement. In this study, a novel FeO nanoparticles and silicone-based powder (SP) were integrated and immobilized on carbon felt (CF+FeO@SP), which was further used as anode in the chlorobenzene (CB) powered MFC. Owing to the cooperation between SP and FeO, the anode exhibited excellent performance for both biodechlorination and power generation. The results indicated that the CF+FeO@SP anode loaded MFC achieved 98.5% removal of 200 mg/L CB within 28 h, and the maximum power density was 675.9 mW/m, which was a 45.6% increase compared to that of the bare CF anode. Microbial community analysis indicated that the genera Comamonadaceae, Pandoraea, Obscuribacteraceae, and Truepera were dominated, especially, the Comamonadaceae and Obscuribacteraceae showed outstanding affinity for FeO and SP, respectively. Moreover, the proportion of live bacteria, secretion of extracellular polymer substances, and protein content in the extracellular polymer substances were significantly increased by modifying FeO@SP onto the carbon-based anode. Thus, this study provides new insights into the development of MFCs for refractory and hydrophobic volatile organic compounds removal.
Topics: Bacteria; Bioelectric Energy Sources; Carbon; Electricity; Electrodes; Polymers; Powders; Volatile Organic Compounds; Water Purification; Water Pollutants, Chemical
PubMed: 37315409
DOI: 10.1016/j.jhazmat.2023.131794 -
Cardiology in the Young Nov 2023Recombinant angiotensin II is an emerging drug therapy for refractory hypotension. Its use is relevant to patients with disruption of the renin-angiotensin-aldosterone...
Recombinant angiotensin II is an emerging drug therapy for refractory hypotension. Its use is relevant to patients with disruption of the renin-angiotensin-aldosterone system denoted by elevated direct renin levels. We present a child that responded to recombinant angiotensin II in the setting of right ventricular hypertension and multi-organism septic shock.
Topics: Humans; Child; Angiotensin II; Hemodynamics; Heart Diseases; Sepsis; Candida
PubMed: 37212085
DOI: 10.1017/S1047951123001221 -
Current Biology : CB Jul 2023The stability of endosymbiotic associations between eukaryotes and bacteria depends on a reliable mechanism ensuring vertical inheritance of the latter. Here, we...
The stability of endosymbiotic associations between eukaryotes and bacteria depends on a reliable mechanism ensuring vertical inheritance of the latter. Here, we demonstrate that a host-encoded protein, located at the interface between the endoplasmic reticulum of the trypanosomatid Novymonas esmeraldas and its endosymbiotic bacterium Ca. Pandoraea novymonadis, regulates such a process. This protein, named TMP18e, is a product of duplication and neo-functionalization of the ubiquitous transmembrane protein 18 (TMEM18). Its expression level is increased at the proliferative stage of the host life cycle correlating with the confinement of bacteria to the nuclear vicinity. This is important for the proper segregation of bacteria into the daughter host cells as evidenced from the TMP18e ablation, which disrupts the nucleus-endosymbiont association and leads to greater variability of bacterial cell numbers, including an elevated proportion of aposymbiotic cells. Thus, we conclude that TMP18e is necessary for the reliable vertical inheritance of endosymbionts.
Topics: Trypanosomatina; Bacteria; Symbiosis; Eukaryota
PubMed: 37201521
DOI: 10.1016/j.cub.2023.04.060 -
Journal of Environmental Management Jul 2023P-Chloro-Meta-Xylenol (PCMX) is a widely used disinfectant. In the current pandemic scenario, its consumption has increased largely, and as a result, wastewater is...
P-Chloro-Meta-Xylenol (PCMX) is a widely used disinfectant. In the current pandemic scenario, its consumption has increased largely, and as a result, wastewater is loaded heavily with PCMX as a contaminant. Remediation of this ecologically toxic phenolic compound is therefore a burning issue. This study proposes an eco-friendly biosorption-based remediation technique to remove PCMX. A novel isolated phenol-resistant gram-negative bacterium, Pandoraea sp. strain BT102, is first encapsulated in biopolymeric calcium alginate beads. These beads are packed in a long adsorption tube and the contaminated water was passed through this packed tube resembling a plug flow reactor. This unique plug-flow set-up is capable of reducing PCMX concentration from 100 mg L to 2.85 μg L within 4 h using only 30 g of adsorbent, resulting in 99.99% removal efficiency. Adsorption isotherms and kinetics are studied using batch experimental data. A PCMX loading capacity of the encapsulated calcium alginate beads is found to be 961.7 mg g, and the Freundlich isotherm results suggested the phenomenon of cooperative adsorption. A good agreement of the pseudo-second-order kinetic model along with the intra-particle diffusion model suggests a multilayer diffusion-controlled adsorption process. Biosorption of PCMX by the bacterium-modified beads was confirmed by Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), and Fourier-Transform Infrared spectroscopy (FT-IR) analyses. The application of multivariate model-based Response Surface Methodology (RSM) reveals flow rate to be the most important factor controlling the rate of bioremediation.
Topics: Alginates; Spectroscopy, Fourier Transform Infrared; Phenols; Bacteria; Adsorption; Kinetics; Hydrogen-Ion Concentration; Water Pollutants, Chemical
PubMed: 36989918
DOI: 10.1016/j.jenvman.2023.117764