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International Journal of Molecular... Oct 2023The healing properties of silver have been used since ancient times. The main aim of the study was to collect and review the literature on the clinical potential of... (Review)
Review
The healing properties of silver have been used since ancient times. The main aim of the study was to collect and review the literature on the clinical potential of silver, its salts and complex compounds. The second goal was to present an outline of the historical use of silver in medicine and pharmacy, taking into account the possibility of producing pharmaceutical drug forms on the premises of pharmacies. In the context of the growing resistance of microorganisms to available, widely used antibiotics, silver plays a key role. There is only one known case of bacterial resistance to silver-the strain, which naturally occurs in silver mines. The development of research in the field of coordination chemistry offers great opportunities in the design of new substances in which silver ions can be incorporated. These substances exhibit increased potency and often an extended antimicrobial spectrum. Silver-based compounds are, however, only limited to external applications, as opposed to their historic oral administration. Advanced studies of their physicochemical, microbiological, cytotoxic and genotoxic properties are ongoing and full of challenges. The improvement of the methods of synthesis gives the possibility of applying the newly synthesized compounds , as was the case with the complex of metronidazole with silver (I) nitrate. Some of these experimental efforts performed in vitro are followed with clinical trials. The third and final goal of this study was to present the possibility of obtaining an ointment under the conditions of an actual pharmacy using silver (I) salts and a ligand, both of which are active substances with antimicrobial properties.
Topics: Silver; Salts; Pharmacies; Anti-Infective Agents; Anti-Bacterial Agents; Silver Compounds; Pharmaceutical Preparations; Pharmacy
PubMed: 37958707
DOI: 10.3390/ijms242115723 -
The Science of the Total Environment May 2020The mechanism of total nitrogen (TN) removal at aerobic condition in wastewater treatment plants (WWTPs) has been one of the most popular research fields. However, the...
The mechanism of total nitrogen (TN) removal at aerobic condition in wastewater treatment plants (WWTPs) has been one of the most popular research fields. However, the role of aerobic denitrification in TN removal was unclear because of the lack of stoichiometric coefficients and kinetic constants of aerobic denitrification bacterium. Thus, this study aimed to investigate the stoichiometry and kinetics of aerobic denitrification by using Pseudomonas stutzeri T13 as a model aerobic denitrification bacterium. Results indicated that strain T13 obtained the maximum yield coefficient (0.1098 mol biomass-N/mol COD) when using NH-N as the sole nitrogen source. This value decreased slightly (0.1077 mol biomass-N/mol COD) during aerobic denitrification, but was still higher than that of conventional denitrification. The half-saturation constants for ammonium, nitrate and nitrite ( [Formula: see text] , [Formula: see text] and [Formula: see text] ) of strain T13 were fitted based on the experimental data and were 2.72, 18.33 and 209.07 mg/L, respectively. The validity of the stoichiometric coefficients and kinetic constants was tested at two extra conditions and perfect fitting results were obtained. To our knowledge, this is the first time to report the stoichiometric coefficients and kinetic constants of aerobic denitrification. These parameters will be useful in modelling nitrogen removal performance in systems inoculated with aerobic denitrification bacterium. Moreover, this study could provide an experimental basis for further clarifying the mechanism of aerobic denitrification from a quantitative perspective.
Topics: Aerobiosis; Ammonium Compounds; Denitrification; Heterotrophic Processes; Kinetics; Nitrification; Nitrites; Nitrogen; Pseudomonas stutzeri
PubMed: 31839288
DOI: 10.1016/j.scitotenv.2019.135181 -
Environmental Research Feb 2023Neonicotinoids (NEOs) are fourth generation pesticides, which emerged after organophosphates, pyrethroids, and carbamates and they are widely used in vegetables, fruits,... (Review)
Review
Neonicotinoids (NEOs) are fourth generation pesticides, which emerged after organophosphates, pyrethroids, and carbamates and they are widely used in vegetables, fruits, cotton, rice, and other industrial crops to control insect pests. NEOs are considered ideal substitutes for highly toxic pesticides. Multiple studies have reported NEOs have harmful impacts on non-target biological targets, such as bees, aquatic animals, birds, and mammals. Thus, the remediation of neonicotinoid-sullied environments has gradually become a concern. Microbial degradation is a key natural method for eliminating neonicotinoid insecticides, as biodegradation is an effective, practical, and environmentally friendly strategy for the removal of pesticide residues. To date, several neonicotinoid-degrading strains have been isolated from the environment, including Stenotrophomonas maltophilia, Bacillus thuringiensis, Ensifer meliloti, Pseudomonas stutzeri, Variovorax boronicumulans, and Fusarium sp., and their degradation properties have been investigated. Furthermore, the metabolism and degradation pathways of neonicotinoids have been broadly detailed. Imidacloprid can form 6-chloronicotinic acid via the oxidative cleavage of guanidine residues, and it is then finally converted to non-toxic carbon dioxide. Acetamiprid can also be demethylated to remove cyanoimine (=N-CN) to form a less toxic intermediate metabolite. A few studies have discussed the neonicotinoid toxicity and microbial degradation in contaminated environments. This review is focused on providing an in-depth understanding of neonicotinoid toxicity, microbial degradation, catabolic pathways, and information related to the remediation process of NEOs. Future research directions are also proposed to provide a scientific basis for the risk assessment and removal of these pesticides.
Topics: Bees; Animals; Insecticides; Neonicotinoids; Pesticides; Insecta; Nitro Compounds; Crops, Agricultural; Biodegradation, Environmental; Mammals
PubMed: 36504008
DOI: 10.1016/j.envres.2022.114953 -
ACS Synthetic Biology Dec 2023The soil environment adjacent to plant roots, termed the rhizosphere, is home to a wide variety of microorganisms that can significantly affect the physiology of nearby...
The soil environment adjacent to plant roots, termed the rhizosphere, is home to a wide variety of microorganisms that can significantly affect the physiology of nearby plants. Microbes in the rhizosphere can provide nutrients, secrete signaling compounds, and inhibit pathogens. These processes could be manipulated with synthetic biology to enhance the agricultural performance of crops grown for food, energy, or environmental remediation, if methods can be implemented in these nonmodel microbes. A common first step for domesticating nonmodel organisms is the development of a set of genetic engineering tools, termed a synthetic biology toolbox. A toolbox comprises transformation protocols, replicating vectors, genome engineering (e.g., CRISPR/Cas9), constitutive and inducible promoter systems, and other gene expression control elements. This work validated synthetic biology toolboxes in three nitrogen-fixing soil bacteria: , (), and a new isolate of . All three organisms were amenable to transformation and reporter protein expression, with several functional inducible systems available for each organism. and showed more reliable plasmid-based expression, resulting in successful Cas9 recombineering to create scarless deletions and insertions. Using these tools, we generated mutants with inducible nitrogenase activity and introduced heterologous genes to produce resorcinol products with relevant biological activity in the rhizosphere.
Topics: Nitrogen; Soil; Synthetic Biology; Plasmids; Genetic Engineering; CRISPR-Cas Systems
PubMed: 37988619
DOI: 10.1021/acssynbio.3c00414 -
Archives of Microbiology Jul 2022Textile wastewater contains dyes mixed with other contaminants in various concentrations. Bacteria-mediated decolorization and degradation of azo dyes have achieved...
Textile wastewater contains dyes mixed with other contaminants in various concentrations. Bacteria-mediated decolorization and degradation of azo dyes have achieved momentum as a method of treatment attributed to their inexpensive, eco-friendly, and application to a wide range of azo dyes. However, a single species of bacteria is inefficient in decolorizing diverse groups of dyes which is one of the most significant challenges for environmental technologists working in bioremediation. In the present study, an aerobic bacterial consortium AUJ consisting of six different bacterial strains (Pseudomonas stutzeri AK1, Pseudomonas stutzeri AK2, Pseudomonas stutzeri AK3, Bacillus spp. AK4, Pseudomonas stutzeri AK5, and Pseudomonas stutzeri AK6) removed the individual azo dyes in the 24-94% range when used in more than 200 ppm concentration within 72-96 h. In addition, the consortium was able to decolorize 52.19% mixed dyes (100 ppm) and 44.55% Acid blue 113 when used at a concentration as high as 1100 ppm within 96 h. Optimization of various nutritional and environmental parameters revealed that glucose and yeast extract were the preferred carbon and nitrogen source, respectively, and analysis of treated dye products using high-performance liquid chromatography (HPLC), Fourier-transform infrared spectroscopy (FTIR), and gas chromatography-mass spectrometry (GC-MS) confirmed the breakdown of dye. In all, we present a bacterial consortium with a good ability of dye decolorization that can be used for degrading a wide variety of azo dyes.
Topics: Azo Compounds; Bacteria; Biodegradation, Environmental; Coloring Agents; Wastewater
PubMed: 35867172
DOI: 10.1007/s00203-022-03108-0 -
Archives of Virology Feb 2021Bacteriophage 8P was isolated with a Pseudomonas stutzeri strain isolated from an oil reservoir as its host bacterium. The phage genome comprises 63,753 base pairs with...
Bacteriophage 8P was isolated with a Pseudomonas stutzeri strain isolated from an oil reservoir as its host bacterium. The phage genome comprises 63,753 base pairs with a G+C content of 64.35. The phage encodes 63 predicted proteins, and 27 of them were functionally assigned. No tRNA genes were found. Comparative genomics analysis showed that 8P displayed some relatedness to F116-like phages (78% identity, 20% query coverage). The genome has very low sequence similarity to the other phage genomes in the GenBank database and Viral Sequence Database. Based on whole-genome analysis and transmission electron microscopy imaging, 8P is proposed to be a member of a new species in the genus Hollowayvirus, family Podoviridae.
Topics: Bacteriophages; Base Composition; DNA, Viral; Genome, Viral; Genomics; Host Specificity; Phylogeny; Podoviridae; Pseudomonas Phages; Pseudomonas stutzeri; Sequence Analysis, DNA
PubMed: 33392816
DOI: 10.1007/s00705-020-04912-z -
Frontiers in Cellular and Infection... 2022Coronavirus disease 2019 (COVID-19) remains a serious emerging global health problem, and little is known about the role of oropharynx commensal microbes in infection...
Coronavirus disease 2019 (COVID-19) remains a serious emerging global health problem, and little is known about the role of oropharynx commensal microbes in infection susceptibility and severity. Here, we present the oropharyngeal microbiota characteristics identified by full-length 16S rRNA gene sequencing through the NANOPORE platform of oropharynx swab specimens from 10 mild COVID-19 patients and 10 healthy controls. Our results revealed a distinct oropharyngeal microbiota composition in mild COVID-19 patients, characterized by enrichment of opportunistic pathogens such as and and depletion of , , and . Based on the relative abundance of the oropharyngeal microbiota at the species level, we built a microbial classifier to distinguish COVID-19 patients from healthy controls, in which , , and were identified as the most prominent signatures for their depletion in the COVID-19 group. Several members of the genus , especially and , which were highly enriched in COVID-19 patients with higher severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral load and showed a significant correlation with disease status and several routine clinical blood indicators, indicate that several bacteria may transform into opportunistic pathogen in COVID-19 patients when facing the challenges of viral infection. We also found the diver taxa and in the network of disease patients, suggesting that these oropharynx microbiota alterations may impact COVID-19 severity by influencing the microbial association patterns. In conclusion, the low sample size of SARS-CoV-2 infection patients (n = 10) here makes these results tentative; however, we have provided the overall characterization that oropharyngeal microbiota alterations and microbial correlation patterns were associated with COVID-19 severity in Anhui Province.
Topics: COVID-19; Humans; Microbiota; Oropharynx; RNA, Ribosomal, 16S; SARS-CoV-2
PubMed: 35372134
DOI: 10.3389/fcimb.2022.824578 -
Synthetic and Systems Biotechnology Dec 2023A1501 is a non-fluorescent denitrifying bacteria that belongs to the gram-negative bacterial group. As a prominent strain in the fields of agriculture and...
A1501 is a non-fluorescent denitrifying bacteria that belongs to the gram-negative bacterial group. As a prominent strain in the fields of agriculture and bioengineering, there is still a lack of comprehensive understanding regarding its metabolic capabilities, specifically in terms of central metabolism and substrate utilization. Therefore, further exploration and extensive studies are required to gain a detailed insight into these aspects. This study reconstructed a genome-scale metabolic network model for A1501 and conducted extensive curations, including correcting energy generation cycles, respiratory chains, and biomass composition. The final model, iQY1018, was successfully developed, covering more genes and reactions and having higher prediction accuracy compared with the previously published model iPB890. The substrate utilization ability of 71 carbon sources was investigated by BIOLOG experiment and was utilized to validate the model quality. The model prediction accuracy of substrate utilization for A1501 reached 90 %. The model analysis revealed its new ability in central metabolism and predicted that the strain is a suitable chassis for the production of Acetyl CoA-derived products. This work provides an updated, high-quality model of A1501for further research and will further enhance our understanding of the metabolic capabilities.
PubMed: 37927897
DOI: 10.1016/j.synbio.2023.10.001 -
AMB Express May 2022Psychrotrophic Pseudomonas is one of the significant microbes that lead to putrefaction in chilled meat. One of the biggest problems in the detection of Pseudomonas is...
Psychrotrophic Pseudomonas is one of the significant microbes that lead to putrefaction in chilled meat. One of the biggest problems in the detection of Pseudomonas is that several species are seemingly identical. Currently, antibiotic resistance is one of the most significant challenges facing the world's health and food security. Therefore, this study was designed to apply an accurate technique for eliminating the identification discrepancy of Pseudomonas species and to study their resistance against various antimicrobials. A total of 320 chicken meat specimens were cultivated, and the isolated bacteria' were phenotypically recognized. Protein analysis was carried out for cultured isolates via Microflex LT. The resistance of Pseudomonas isolates was recorded through Vitek® 2 AST-GN83 cards. Overall, 69 samples were identified as Pseudomonas spp. and included 18 Pseudomonas lundensis (P. lundensis), 16 Pseudomonas fragi (P. fragi), 13 Pseudomonas oryzihabitans (P. oryzihabitans), 10 Pseudomonas stutzeri (P. stutzeri), 5 Pseudomonas fluorescens (P. fluorescens), 4 Pseudomonas putida (P. putida), and 3 Pseudomonas aeruginosa (P. aeruginosa) isolates. Microflex LT identified all Pseudomonas isolates (100%) correctly with a score value ≥ 2.00. PCA positively discriminated the identified isolates into various groups. The antimicrobial resistance levels against Pseudomonas isolates were 81.16% for nitrofurantoin, 71% for ampicillin and ampicillin/sulbactam, 65.22% for cefuroxime and ceftriaxone, 55% for aztreonam, and 49.28% for ciprofloxacin. The susceptibilities were 100% for cefotaxime, 98.55% for ceftazidime, 94.20% for each piperacillin/tazobactam and cefepime, 91.3% for cefazolin. In conclusion, chicken meat was found to be contaminated with different Pseudomonas spp., with high incidence rates of P. lundensis. Microflex LT is a potent tool for distinguishing Pseudomonads at the species level.
PubMed: 35532863
DOI: 10.1186/s13568-022-01390-1 -
Turkish Journal of Pharmaceutical... Feb 2021Tamoxifen (TAM), which is used for treating breast cancer, has exhibited another important function as an antimicrobial agent. The objective of this study is to...
OBJECTIVES
Tamoxifen (TAM), which is used for treating breast cancer, has exhibited another important function as an antimicrobial agent. The objective of this study is to investigate the antibacterial action of TAM against the bacteria present in the human oral cavity.
MATERIALS AND METHODS
The bacteria present in the human oral cavity were isolated from healthy individuals. Different concentrations of TAM were tested against the isolated bacteria. Additionally, bactericidal and bacteriostatic effects of TAM were also determined.
RESULTS
Out of 23 isolated bacteria, a greater number of Gram-positive bacteria were highly susceptible to the low concentrations of TAM than Gram-negative bacteria. , which is Gram-positive bacterium, and , which is Gram-negative bacterium, needed a high minimum inhibitory concentration value of TAM (2.5 mg/mL) to be inhibited by TAM's bacteriostatic action. Resistance to TAM was also observed in three strains of Gram-positive and four strains of Gram-negative bacteria.
CONCLUSION
TAM has shown a potential antibacterial effect against the bacteria present in the oral cavity, especially against Gram-positive bacteria. This effect is mostly bacteriostatic. This study also found bacterial resistance toward TAM.
PubMed: 33634670
DOI: 10.4274/tjps.galenos.2019.23500