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PloS One 2020High concentrations of metals in the environment alter bacterial diversity, selecting resistant and tolerant species. The study evaluated the selection of a potential...
High concentrations of metals in the environment alter bacterial diversity, selecting resistant and tolerant species. The study evaluated the selection of a potential bacterial strain from Sepetiba Bay-Rio de Janeiro, Brazil marine sediments to remove Cu and Pb. The bacterial strain isolated from the sediments was used in three different bioassays: (1) Cu at concentrations of 0 (control), 6 and 50 μg.mL-1; (2) Pb at concentrations of 0 (control), 6 and 50 μg.mL-1; (3) Cu + Pb in concentrations of 3 μg.mL-1 Cu + 3 μg.mL-1 Pb (6 μg.mL-1) and 25 μg.mL-1 Cu + 25 μg.mL-1 Pb (50 μg.mL-1). The number of cells and the enzymatic activities of dehydrogenases and esterases were quantified. Results of taxonomic identification indicated the selection of the Pseudomonas stutzeri W228 strain, showing a greater degree of similarity (±73%) with the database used. There was no significant variation in the number of cells, 108 cells.mL-1, which represents a high biomass production in the presence of stressors. However, we observed a reduction in dehydrogenase activity at all tested concentrations of Cu, Pb and Cu + Pb. The activity of esterase increased, indicating a higher energy demand to complete the bacterial life cycle. The study showed significant results for the absorption of Pb by the extracellular polymeric substances (EPS) and the efflux of Cu. The capacity of Pb absorption by EPS can be considered a resistance mechanism, as well as the efflux of Cu, so that the available EPS sites could be occupied by the most toxic ions demonstrating that Pseudomonas stutzeri is resistant to Pb and Cu.
Topics: Bacterial Proteins; Bacteriological Techniques; Biodegradation, Environmental; Biomass; Brazil; Copper; Esterases; Extracellular Polymeric Substance Matrix; Gene Expression Regulation, Bacterial; Gene Expression Regulation, Enzymologic; Geologic Sediments; Lead; Oxidoreductases; Pseudomonas stutzeri; Water Pollutants, Chemical
PubMed: 33104697
DOI: 10.1371/journal.pone.0240486 -
International Journal of Nanomedicine 2020Selenium nanoparticles (SeNP) have several applications in the field of biotechnology, including their use as anti-cancer drugs. The purpose of the present study is to...
PURPOSE
Selenium nanoparticles (SeNP) have several applications in the field of biotechnology, including their use as anti-cancer drugs. The purpose of the present study is to analyze the efficacy of green synthesis on the preparation of SeNP and its effect on their anti-cancer properties.
METHODS
A bacterial strain isolated from a freshwater source was shown to efficiently synthesize SeNP with potential therapeutic properties. The quality and stability of the NP were studied by scanning electron microscopy, X-ray diffraction, zeta-potential and FTIR analysis. A cost-effective medium formulation from biowaste having 6% banana peel extract enriched with 0.25 mM tryptophan was used to synthesize the NP. The NP after optimization was used to analyze their anti-tumor and anti-angiogenic activity. For this purpose, first, the cytotoxicity of the NP against cancer cells was analyzed by MTT assay and then chorioallantoic membrane assay was performed to assess anti-angiogenic activity. Further, cell migration assay and clonogenic inhibition assay were performed to test the anti-tumor properties of SeNP. To assess the cytotoxicity of SeNP on healthy RBC, hemolysis assay was performed.
RESULTS
The strain identified as (MH191156) produced phenazine carboxylic acid, which aids the conversion of Se oxyanions to reduced NP state, resulting in particles in the size range of 75 nm to 200 nm with improved stability and quality of SeNP, as observed by zeta (ξ) potential of the particles which was found to be -46.2 mV. Cytotoxicity of the SeNP was observed even at low concentrations such as 5 µg/mL against cervical cancer cell line, ie, HeLa cells. Further, neovascularization was inhibited by upto 30 % in CAMs of eggs coinoculated with SeNp when compared with untreated controls, indicating significant anti-angiogenic activity of SeNP. The NP also inhibited the invasiveness of HeLa cells as observed by decreased cell migration and clonogenic proliferation. These observations indicate significant anti-tumor and anti-angiogenic activity of the SeNP in cervical cancer cells.
CONCLUSION
(MH191156) is an efficient source of Se NP production with potential anti-angiogenic and anti-tumor properties, particularly against cervical cancer cells.
Topics: Angiogenesis Inhibitors; Animals; Antineoplastic Agents; Cell Death; Cell Movement; Cell Proliferation; Cell Survival; Chick Embryo; Costs and Cost Analysis; Female; HeLa Cells; Hemolysis; Humans; Metal Nanoparticles; Phenazines; Pseudomonas stutzeri; Reproducibility of Results; Selenium; Spectroscopy, Fourier Transform Infrared; Static Electricity; Uterine Cervical Neoplasms; X-Ray Diffraction
PubMed: 32606692
DOI: 10.2147/IJN.S247426 -
3 Biotech Feb 2023Toxic polycyclic aromatic hydrocarbons (PAHs) are often released into the environment during the combustion and processing of fossil fuels and are capable of causing...
UNLABELLED
Toxic polycyclic aromatic hydrocarbons (PAHs) are often released into the environment during the combustion and processing of fossil fuels and are capable of causing significant pollution to people and the environment. One of the representative substances of PAHs is phenanthrene, which is often studied as a model compound for PAHs treatment. In this study, we compared the results of transcriptome analysis of in two different culture conditions under phenanthrene-induced culture (test group) and glucose-induced culture (control group), and analysed the key enzymatic mechanisms of in the biodegradation of phenanthrene. In our experiments, the transcriptome results showed that a total of 380 genes were more than twofold differentially expressed in the test group, of which 187 genes were significantly up-regulated in expression under Phenanthrene induction. Among the 380 differentially expressed genes, 90 genes were involved in Phenanthrene biodegradation, mainly including genes involved in biometabolism, cellular chemotaxis, substrate transport, signal induction and other related processes. Based on the transcriptome sequence analysis of at the time of phenanthrene induction, a total of 25 dioxygenase genes were identified, and the related genes were mainly concentrated in two relatively concentrated clusters of PAHs biodegradation genes. The transcriptome analysis resulted in a complete set of enzyme genes related to the phenanthrene biodegradation pathway. The analysis of key enzymes led to the inference of a possible phenanthrene biodegradation pathway: the salicylic acid degradation pathway. The results of this study provide a theoretical basis for in situ remediation of PAHs-contaminated environments using .
SUPPLEMENTARY INFORMATION
The online version contains supplementary material available at 10.1007/s13205-023-03473-7.
PubMed: 36718409
DOI: 10.1007/s13205-023-03473-7 -
The Science of the Total Environment Aug 2020Functional durability of bio-augmented microbes in contaminated fields remains a major challenge in bioremediation. In the present study, various immobilization...
Functional durability of bio-augmented microbes in contaminated fields remains a major challenge in bioremediation. In the present study, various immobilization materials and compositional combinations were designed and compared to enhance the functional durability of Pseudomonas stutzeri sp. Y2 for degradation of simazine, one of the most used herbicides, in industrial wastewater and maize fields. Among four combinations of materials tested, the optimal combination obtained from the orthogonal array trials was 14% polyvinyl alcohol (PVA), 1-3% sodium alginate (SA), 2% activated carbon (AC), and 1-2% Y2 cells (PSC-Y2), which yielded 1.7 fold faster degradation of simazine at 50 mg L than that by free Y2 cells in the industrial wastewater. The degradation half-lives (DT) of simazine (10 mg L) by free Y2 cells and PSC-Y2 was 1.1 d and 5.3 d in laboratory soil, respectively. The DT of simazine by PSC-Y2 at the recommended and double dosages of simazine (0.45 and 0.9 g ai·m) was 17.2 d and 12.4 d in the maize fields, respectively, in comparison with 23 d and 17.4 d by free Y2 cells. In addition, the PSC-Y2 degraded 100% of atrazine and terbuthylazine, and 96% of propazine at an initial concentration of 50 mg L each in 4 days. This study provides an immobilization strategy to stabilize bacteria and prolong bacterial functions to treat s-triazine herbicides contaminated water and soil.
Topics: Atrazine; Herbicides; Pseudomonas stutzeri; Simazine; Triazines; Wastewater; Zea mays
PubMed: 32388161
DOI: 10.1016/j.scitotenv.2020.139183 -
Scientific Reports Feb 2021The bacterium Pseudomonas stutzeri SPM-1, obtained from textile wastewater dumping sites of Surat, Gujarat was studied for the degradation of the textile azo dye Procion...
The bacterium Pseudomonas stutzeri SPM-1, obtained from textile wastewater dumping sites of Surat, Gujarat was studied for the degradation of the textile azo dye Procion Red-H3B. The optimization was carried on the phenanthrene enrichment medium followed by exposing it to variable environmental factors and nutritional sources. The complete decolorization of dye (50 mg/L) happened within 20 h of incubation at pH 8 and temperature 32 ± 0.2 °C under microaerophilic conditions. Decolourization was monitored with the shifting of absorbance peak in UV-Vis spectrophotometry and HPLC analysis. The physicochemical studies of effluent before and after the treatment revealed 85%, 90%, and 65% decline in BOD, COD, and TOC levels. The strain showed significant activities of azoreductase (95%), laccase (76%), and NADH-DCIP reductase (88%) at 12 h, 10 h, and 8 h of growth respectively indicating evidence for reductive cleavage of the dye. The changes in the functional groups were confirmed by the presence of new peaks in FT-IR data. GC-MS analysis helped in recognizing the degraded dye compounds thus elucidating the proposed pathway for degradation of Procion Red-H3B. The potential of the bioremediation process was concluded by a phytotoxicity test using two plants, Vigna radiata and Cicer arietinum. Our study demonstrates that the strain Pseudomonas stutzeri SPM-1 has rapid decolorization efficiency and holds a noteworthy perspective in industrial application for textile wastewater treatment.
Topics: Azo Compounds; Biodegradation, Environmental; Gas Chromatography-Mass Spectrometry; Humans; Pseudomonas stutzeri; Spectroscopy, Fourier Transform Infrared; Triazines; Wastewater; Water Pollutants, Chemical; Water Purification
PubMed: 33542307
DOI: 10.1038/s41598-021-82494-9 -
Bioscience, Biotechnology, and... Jul 2023d-Aldotetroses are rare sugars that are obtained via chemical synthesis in low yield. In this study, we demonstrated that d-aldotetroses could be produced using 3...
d-Aldotetroses are rare sugars that are obtained via chemical synthesis in low yield. In this study, we demonstrated that d-aldotetroses could be produced using 3 isomerases. First, l-erythrulose was epimerized using d-tagatose 3-epimerase from Pseudomonas cichorii ST-24. The specific optical rotation of the reaction solution gradually decreased to zero, indicating that approximately 50% of the l-erythrulose was converted to d-erythrulose. d, l-Erythrulose mixture was isomerized with d-arabinose isomerase from Klebsiella pneumoniae 40bXX to produce d-threose, resulting in a conversion rate of 9.35%. d-Erythrose production using l-rhamnose isomerase from Pseudomonas stutzeri LL172 resulted in a conversion rate of 12.9%. Because of the low purity of the purchased d-erythrose, the product was reduced by the Raney nickel catalyst compared with authentic erythritol. We confirmed the products using HPLC and 13C-NMR spectra. This is the first report of d-aldotetrose production using an enzymatic reaction.
Topics: Tetroses; Hexoses; Isomerases; Aldose-Ketose Isomerases; Racemases and Epimerases
PubMed: 37156528
DOI: 10.1093/bbb/zbad058 -
Journal of Visualized Experiments : JoVE Jan 2022Melanins are natural pigments, and the presence of indole ring and numerous functional groups makes melanin an ideal choice for many applications such as UV protective...
Melanins are natural pigments, and the presence of indole ring and numerous functional groups makes melanin an ideal choice for many applications such as UV protective agents, skincare, cosmetics etc. A marine Pseudomonas stutzeri produces melanin without the addition of tyrosine. The feedback inhibition was observed by melanin in the culture of a melanin-producing marine bacterium, Pseudomonas stutzeri. Melanin also demonstrated microbial growth inhibition. The Han-Levenspiel model-based analysis identified uncompetitive type product inhibition of melanin on the cell growth. Tyrosinase enzyme, which produces melanin, was inhibited by melanin. The double reciprocal plot of the enzymatic reaction in the presence of different melanin concentrations revealed uncompetitive product inhibition. An adsorbent-based adsorptive bioprocess was developed to reduce the feedback inhibition by melanin. Different adsorbents were screened to select the best adsorbent for melanin adsorption. Dosage amount and time were optimized to develop the adsorptive bioprocess, which resulted in an 8.8-fold enhancement in melanin production by the marine bacteria Pseudomonas stutzeri (153 mg/L to 1349 mg/L) without supplementation of tyrosine and yeast extract.
Topics: Adsorption; Cosmetics; Melanins; Pseudomonas stutzeri; Tyrosine
PubMed: 35098948
DOI: 10.3791/63339 -
Applied and Environmental Microbiology Feb 2021Diazotrophs can produce bioavailable nitrogen from inert N gas by bioelectrochemical nitrogen fixation (-BNF), which is emerging as an energy-saving and highly selective...
Diazotrophs can produce bioavailable nitrogen from inert N gas by bioelectrochemical nitrogen fixation (-BNF), which is emerging as an energy-saving and highly selective strategy for agriculture and industry. However, current -BNF technology is impeded by requirements for NH assimilation inhibitors to facilitate intracellular ammonia secretion and precious metal catalysts to generate H as the energy-carrying intermediate. Here, we initially demonstrate inhibitor- and catalystless extracellular NH production by the diazotroph Pseudomonas stutzeri A1501 using an electrode as the sole electron donor. Multiple lines of evidence revealed that P. stutzeri produced 2.32 ± 0.25 mg/liter extracellular NH at a poised potential of -0.3 V (versus standard hydrogen electrode [SHE]) without the addition of inhibitors or expensive catalysts. The electron uptake mechanism was attributed to the endogenous electron shuttle phenazine-1-carboxylic acid, which was excreted by P. stutzeri and mediated electron transfer from electrodes into cells to directly drive N fixation. The faradaic efficiency was 20% ± 3%, which was 2 to 4 times that of previous -BNF attempts using the H-mediated pathway. This study reports a diazotroph capable of producing secretable NH via extracellular electron uptake, which has important implications for optimizing the performance of -BNF systems and exploring the novel nitrogen-fixing mode of syntrophic microbial communities in the natural environment. Ammonia greatly affects global ecology, agriculture, and the food industry. Diazotrophs with an enhanced capacity of extracellular NH excretion have been proven to be more beneficial to the growth of microalgae and plants, whereas most previously reported diazotrophs produce intracellular organic nitrogen in the absence of chemical suppression and genetic manipulation. Here, we demonstrate that Pseudomonas stutzeri A1501 is capable of extracellular NH production without chemical suppression or genetic manipulation when the extracellular electrode is used as the sole electron donor. We also reveal the electron uptake pathway from the extracellular electron-donating partner to P. stutzeri A1501 via redox electron shuttle phenazines. Since both P. stutzeri A1501 and potential electron-donating partners (such as electroactive microbes and natural semiconductor minerals) are abundant in diverse soils and sediments, P. stutzeri A1501 has broader implications on the improvement of nitrogen fertilization in the natural environment.
Topics: Ammonia; Nitrogen Fixation; Pseudomonas stutzeri
PubMed: 33310714
DOI: 10.1128/AEM.01998-20 -
Infection and Drug Resistance 2021To investigate the genomic and plasmid characteristics of a newly discovered strain with a -carrying plasmid and novel integron In isolated from a cerebrospinal fluid...
PURPOSE
To investigate the genomic and plasmid characteristics of a newly discovered strain with a -carrying plasmid and novel integron In isolated from a cerebrospinal fluid specimen in a teaching hospital.
METHODS
Species identification was performed by MALDI-TOF MS, and was identified by PCR and Sanger sequencing. Whole-genome sequencing analysis was conducted using the Illumina NovaSeq 6000 and Oxford Nanopore platforms. Integron detection was performed using INTEGRALL. The phylogenetic tree was constructed by using kSNP3.0. Plasmid characteristics were assessed by S1-pulsed-field gel electrophoresis (S1-PFGE), Southern blotting, conjugation experiments, and whole-genome sequencing analysis. Comparative genomics analysis of the plasmid and genetic context of were conducted by using BLAST Ring Image Generator (BRIG) and Easyfig 2.3, respectively.
RESULTS
ZDHY95, an MDR strain of harboring , was identified. It was sensitive only to amikacin and was resistant to carbapenems, β-lactams, aztreonam, fluoroquinolones, and aminoglycosides. Joint S1-PFGE, Southern blot, conjugation assay, and whole-genome sequencing experiments confirmed that the gene was located within class I integron In of the plasmid and that the surrounding genetic environment was 5'CS- --3'CS. The novel class I integron In was detected on the chromosome of ZDHY95, and the gene cassette array was 5'CS- --3'CS. Phylogenetic analysis showed that antimicrobial resistance gene-carrying isolates were divided into two clusters, mainly containing isolates from the USA and Pakistan.
CONCLUSION
A novel -carrying conjugative plasmid, pZDHY95-VIM-2, was reported for the first time in , elucidating the genetic environment and transfer mechanism. The gene structure of the novel class I integron In was also clarified. We explored the phylogenetic relationship of with drug resistance genes and suggested that with metallo-β-lactamases (MBLs) in the hospital environment may cause infection in patients with long-term intubation or after interventional surgery.
PubMed: 34466007
DOI: 10.2147/IDR.S320294 -
Journal of Medical Case Reports Oct 2021Pseudomonas stutzeri is a nonfluorescent denitrifying bacterium widely distributed in the environment, and it has also been isolated as an opportunistic pathogen from... (Review)
Review
BACKGROUND
Pseudomonas stutzeri is a nonfluorescent denitrifying bacterium widely distributed in the environment, and it has also been isolated as an opportunistic pathogen from humans. It is a Gram-negative bacterium and a common inhabitant of soil and water.
CASE PRESENTATION
We report the case of a 51-year-old arab gentleman who has systemic lupus erythematous complicated by lupus nephritis and underwent renal transplantation twice. He underwent mitral valve replacement and 4 years later was diagnosed with prosthetic valve endocarditis caused by Pseudomonas stutzeri.
CONCLUSIONS
Literature review was conducted and revealed that this pathogen may be of a particular medical relevance in immunocompromised patients. Our case proves that early infection and relapse despite optimal antibiotics course are possible outcomes of Pseudomonas stutzeri endocarditis. To the best of our knowledge, this is the second case of fulminant early prosthetic valve endocarditis occurring only 1 month post-cardiac surgery with relapse despite a complete antibiotics course.
Topics: Anti-Bacterial Agents; Endocarditis, Bacterial; Heart Valve Prosthesis; Humans; Male; Middle Aged; Pseudomonas stutzeri
PubMed: 34627386
DOI: 10.1186/s13256-021-03084-x