scholarly journals On the Ability of Perfluorohexane Sulfonate (PFHxS) Bioaccumulation by Two Pseudomonas sp. Strains Isolated from PFAS-Contaminated Environmental Matrices

2020 ◽  
Vol 8 (1) ◽  
pp. 92 ◽  
Author(s):  
Alessandro Presentato ◽  
Silvia Lampis ◽  
Andrea Vantini ◽  
Flavio Manea ◽  
Francesca Daprà ◽  
...  
Keyword(s):  
Short Chain ◽  
Industrial Processes ◽  
Bacterial Cells ◽  
Pseudomonas Sp ◽  
Environmental Matrices ◽  
Synthetic Compounds ◽  
Physiological Conditions ◽  
End Products ◽  
Polyfluoroalkyl Substances ◽  
Thermal And Chemical Stability

PFASs (perfluoroalkyl and polyfluoroalkyl substances) are highly fluorinated, aliphatic, synthetic compounds with high thermal and chemical stability as well as unique amphiphilic properties which make them ingredients in a range of industrial processes. PFASs have attracted consideration due to their persistence, toxicity and bioaccumulation tendency in the environment. Recently, attention has begun to be addressed to shorter-chain PFASs, such as perfluorohexane sulfonate [PFHxS], apparently less toxic to and more easily eliminated from lab animals. However, short-chain PFASs represent end-products from the transformation of fluorotelomers whose biotic breakdown reactions have not been identified to date. This means that such emergent pollutants will tend to accumulate and persist in ecosystems. Since we are just learning about the interaction between short-chain PFASs and microorganisms, this study reports on the response to PFHxS of two Pseudomonas sp. strains isolated from environmental matrices contaminated by PFASs. The PFHxS bioaccumulation potential of these strains was unveiled by exploiting different physiological conditions as either axenic or mixed cultures under alkanothrofic settings. Moreover, electron microscopy revealed nonorthodox features of the bacterial cells, as a consequence of the stress caused by both organic solvents and PFHxS in the culturing substrate.

scholarly journals Influence of Supplementation of Lactoferrin, Melittin and Cecropin A to Rat Diet on Changes in Faecal Ammonia Concentrations, Short-Chain Fatty Acid Concentrations and Activities of Bacterial Enzymes

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1203
Author(s):  
Jerzy Juśkiewicz ◽  
Aleksandra Rawicka ◽  
Bartosz Fotschki ◽  
Michał Majewski ◽  
Zenon Zduńczyk
Keyword(s):  
Fatty Acid ◽  
Short Chain Fatty Acid ◽  
Control Diet ◽  
Chain Fatty Acid ◽  
Short Chain ◽  
Antimicrobial Protein ◽  
Enzyme Release ◽  
Bacterial Cells ◽  
Suppression Effect ◽  
Cecropin A

We hypothesised that the dietary addition of the bioactive antimicrobial protein lactoferrin (LF) and peptides melittin (MT) or cecropin A (CR) at a dosage of 100 mg/kg to the diet of Wistar rats would result in strong modulatory effects on faecal microbial enzymatic activity, short-chain fatty acid and ammonia concentrations. To date, the changes in bacterial extracellular and intracellular enzymatic activities upon addition of dietary AMPs have not yet been studied. This experiment lasted 15 days; during the first 5 day period, the rats were fed the control diet (S) and diets supplemented with LF, MT or CR. On days 6–15, all rats were fed the control S diet. The faecal fermentation processes were substantially stopped after two days of treatment, on average, in all rats receiving LF and two AMPs. The deepest suppression effect was observed on the last day of treatment (day 5) and persisted through days 5–8. The highest decreases in faecal bacterial β-glucosidase and β-glucuronidase activities as well as in SCFA and ammonia concentrations were observed in the rats fed the CR diet. Only in the CR animals did the mechanism of suppressed microbial fermentation involve diminished enzyme release from bacterial cells to the digesta.

scholarly journals Analysis and identification of Pseudomonas sp. and molds on dried anchovy (Stelophorus sp) products produced by the people of Toniku Village, Halmahera Barat Regency, North Maluku Province

2019 ◽  
Vol 3 (1) ◽  
pp. 1
Author(s):  
Ruslan A. Daeng ◽  
Azis Husen
Keyword(s):  
Plate Count ◽  
Bacterial Cells ◽  
Pseudomonas Sp ◽  
Fishing Community ◽  
Total Plate Count ◽  
The People ◽  
Sampling Locations ◽  
Preparation Stage ◽  
Three Stages ◽  
Identification Stage

This research was conducted to determine the characteristics of Pseudomonas sp. and mold on dried anchovies. The sample in this study was obtained from the fishing community of Toniku Village, West Halmahera Regency, North Maluku Province. The stages carried out in this study were 3 (three) stages, namely the sample preparation stage, the analysis phase and the identification stage of Pseudomonas sp. and mold. The results showed that the characteristics of the Total Plate Count (TPC) of dried anchovy in the Toniku Village obtained a different composition from each other, with the highest log Total Plate Count (TPC) obtained, namely 5.5 or 3.2 x 105 Cfu/g or 320.000 cells bacteria, while the lowest Total Plate Count (TPC) log was obtained, 2.5 or 3.1 x 102 Cfu/g or 310 bacterial cells and for total Pseudomonas bacteria from the three sampling locations no growth was found. The highest total log fungi were obtained ie 5.6 or 3.7 x 105 Cfu/g or 370.000 mold cells, while the lowest total log fungi were obtained which were 2.4 or 2.6 x 102 Cfu/g or 260 mold cells

Immobilization of Phenol Degrader Pseudomonas sp In Repeated Batch Culture Using Bioceramic and Sponge as Support Materials

2012 ◽  
Author(s):  
Mailin Misson ◽  
Firdausi Razali
Keyword(s):  
Batch Culture ◽  
Packed Column ◽  
Tolerance Limit ◽  
Phenol Removal ◽  
Bacterial Cells ◽  
Pseudomonas Sp ◽  
Support Materials ◽  
Removal Capacity ◽  
Repeated Batch Culture ◽  
Repeated Batch

Prestasi dua jenis penyokong yang lengai iaitu bioseramik dan span untuk menyekat gerak bakteria pengurai fenol Pseudomonas sp di dalam turus terpadat telah dikaji dalam kultur kelompok berulang. Sebelum ini, kajian kami menunjukkan bahawa penyekat gerakan telah menggandakan had daya tahan mikrob terhadap kepekatan fenol dari 1000 ppm (dalam kultur ampaian) ke 2000 ppm. Pada isipadu yang sama, bioseramik berupaya memerangkap sel bakteria 1.8 kali lebih banyak daripada span. Oleh itu, ia berupaya mengurai 100% fenol yang berkepekatan 1000 ppm dalam masa 24 jam pada kadar alir suapan 2.5 ml/min, dan mengulangi prestasi yang sama dalam enam kelompok berturut–turut seterusnya. Namun demikian, sel yang terperangkap dalam span hanya berupaya mengurai 90% fenol dalam lima kelompok. Walaupun prestasinya lebih rendah, penggunaan span untuk memerangkap sel dalam skala yang besar memberikan beberapa kebaikan seperti ringan dan senang diperoleh pada harga yang lebih murah. Kata kunci: Tersekat gerak, fenol, Pseudomonas sp, bioseramik, kultur kelompok berulang The performance of two types of inert support, namely bioceramic and sponge to immobilize a locally isolated phenol degrader Pseudomonas sp. in a packed column was investigated in repeated batch culture. Prior to this, our study indicated that immobilization had doubled the tolerance limit of the cells towards phenol from 1000 ppm (in the suspended culture), to 2000 ppm. For the same volume, the bioceramic managed to trap bacterial cells 1.8 times greater than the sponge did. As a result, it was able to remove 100% of 1000 ppm 600–ml phenol fed at a rate of 2.5 ml/min within 24 hours, and the phenol removal capacity was sustained in the next six consecutive batches. Cells entrapped in sponge however, managed to remove around 90% phenol in five batches. Despite lower performance, at large scales, the use of sponge for cell entrapment offers some merits such as lightness, and easily available at cheaper cost. Key words: Immobilization, phenol, Pseudomonas sp, bioceramic, repeated batch

The growth inhibition of Azotobacter chroococcum by Pseudomonas sp.

1970 ◽  
Vol 16 (1) ◽  
pp. 9-16 ◽  
Author(s):  
E. C. S. Chan ◽  
Pramila Basavanand ◽  
Tiiu Liivak
Keyword(s):  
Agar Medium ◽  
High Sensitivity ◽  
Azotobacter Chroococcum ◽  
Point Of View ◽  
Pseudomonas Sp ◽  
Microbial Interaction ◽  
Metabolic Intermediates ◽  
Microbial Association ◽  
End Products ◽  
Diffusible Factor

When Azotobacter chroococcum and Pseudomonas sp. were grown together on nitrogen-deficient azotobacter agar medium, the growth of the azotobacter was inhibited. Studies were undertaken to explain this microbial interaction. No demonstrable active diffusible factor was found in cell-free filtrates (neutralized) and extracts. Experiments with indicator agar plates and HEPES-buffered liquid medium suggested that the interaction was attributable to the transformation by the pseudomonad of metabolic intermediates of azotobacter to inhibitory acidic end products. The high sensitivity of A. chroococcum to acidity resulted in the inhibition phenomenon. This microbial association is discussed briefly from the point of view of the ecology of the two species.

scholarly journals Peptide Deformylase as an Antibacterial Drug Target: Assays for Detection of Its Inhibition in Escherichia coli Cell Homogenates and Intact Cells

2001 ◽  
Vol 45 (4) ◽  
pp. 1053-1057 ◽  
Author(s):  
Christian M. Apfel ◽  
Stefan Evers ◽  
Christian Hubschwerlen ◽  
Wolfgang Pirson ◽  
Malcolm G. P. Page ◽  
...  
Keyword(s):  
Drug Target ◽  
Peptide Deformylase ◽  
Translation System ◽  
Antibacterial Drug ◽  
Bacterial Cells ◽  
Methionine Aminopeptidase ◽  
Intact Cells ◽  
Physiological Conditions ◽  
A Cell ◽  
Antibacterial Drug Target

ABSTRACT An assay was developed to determine the activity of peptide deformylase (PDF) inhibitors under conditions as close as possible to the physiological situation. The assay principle is the detection of N-terminal [35S]methionine labeling of a protein that contains no internal methionine. If PDF is active, the deformylation of the methionine renders the peptide a substrate for methionine aminopeptidase, resulting in the removal of the N-terminal methionine label. In the presence of a PDF inhibitor, the deformylation is blocked so that the N-formylated peptide is not processed and the label is detected. Using this assay, it is possible to determine the PDF activity under near-physiological conditions in a cell-free transcription-translation system as well as in intact bacterial cells.

scholarly journals Short-chain chlorinated paraffins in biota – levels and effects

2013 ◽  
Vol 14 (1) ◽  
pp. 66-71
Keyword(s):  
Flame Retardants ◽  
Water Solubility ◽  
Atmospheric Transport ◽  
Carbon Chain ◽  
Short Chain ◽  
The Arctic ◽  
Environmental Matrices ◽  
Flame Resistance ◽  
Chlorinated Paraffins ◽  
Chain Lengths

Short-chain chlorinated paraffins (SCCPs) are highly complex technical mixtures of polychlorinated n-alkanes with carbon-chain lengths from C10-C13 and chlorine content between 49 and 70%. They are produced by chlorination of n-alkanes and do not occur naturally. Because of their physical properties (viscosity, flame resistance) they are used in many different applications, such as lubricant additives, PVC plasticizers and flame retardants in paints, adhesives and sealants. Among the chlorinated paraffin mixtures, SCCPs have the highest potential for release into the environment, because of their higher vapour pressure and water solubility (about 10-100 times higher than for PCBs). SCCPs can reach the environment through production, storage or use, as well as through leeching, runoff and volatilization from contaminated areas. Despite the fact that they are one of the most challenging groups of compounds to quantify and analyze, SCCPs have been detected in biota and humans, as well as a variety of environmental matrices such as sediments and air. SCCPs have also been detected in remote places such as the Arctic (Reth et al., 2006) and dated sediment cores, suggesting long-range atmospheric transport and persistence in the environment. SCCPs have been found to be toxic to aquatic and soil organisms, fish and there is some evidence of carcinogenicity. This paper reviews the current state of knowledge and highlights the need for further research in order to improve future monitoring efforts.

scholarly journals Proteomic Examination for Gluconeogenesis Pathway-Shift during Polyhydroxyalkanoate Formation in Cupriavidus necator Grown on Glycerol

2020 ◽  
Vol 7 (4) ◽  
pp. 154
Author(s):  
Nuttapol Tanadchangsaeng ◽  
Sittiruk Roytrakul
Keyword(s):  
Mass Spectrometry ◽  
Glycosyl Hydrolase ◽  
Expression Patterns ◽  
Polyacrylamide Gel Electrophoresis ◽  
Cupriavidus Necator ◽  
Production Costs ◽  
Raw Material ◽  
Short Chain ◽  
Bacterial Cells ◽  
Glucose Content

Because of availability and inexpensiveness, glycerol can be considered as a suitable raw material for polyhydroxyalkanoate (PHA) production with bacterial fermentation. Nevertheless, compared to the production of glucose as a raw precursor, PHA produced from glycerol by Cupriavidus necator was found to produce lower PHA with low bacterial growth rates. According to our study, C. necator was able to synthesize glucose-like intermediates from glycerol via gluconeogenesis. This resulted in a decrease of the cell dry weight and the yield of PHA polymers, especially in the active cell growth phase. It was indicated that glycerol used as a carbon source of the PHA synthesis pathway has glucogenesis-shift, which causes a decrease of the PHA content and productivity. In this research, we investigated the proteins that were closely expressed with the increase of the intracellular PHA and glucose content. For solving the above problem, the proteins inside the bacterial cells were analyzed and compared to the database proteins via mass spectrometry. The proteins were isolated by 1-D SDS-polyacrylamide gel electrophoresis (PAGE) technique and identified by the liquid chromatography mass spectrometry (LC-MS) technique. By using bioinformatics validation, a total number of 1361 proteins were examined and found in the culture bacterial cells. Selective protein expression was correlated with the amount of PHA at each cultivation time and generating glucose by studying the 1361 proteins was elucidated in proteomic information. The results of the cluster of proteins were found to contain 93 proteins using the multiple array viewer (MEV) program with the KMS data analysis model. Protein species with the same expression pattern for PHA and six proteins with similar expression patterns were found to be correlated with generating glucose content. The associations of the two protein groups were then determined through a Stitch program. The protein and chemical associations were analyzed both directly and indirectly through different databases. The proteins of interest were found with research data linked between glycerol and glucose. Five protein types are connecting to glucose and glycerol shift pathway, two of which are glycosyl hydrolase (H16_B1563) and short-chain dehydrogenase (H16_B0687), both of which are enzymes used to break the bonds of complex sugars, possibly related to the partial conversion of glycerol to glucose. The two proteins found in the strains used in the Cupriavidus necator H16 experiment give rise to the break down the bonds of α,α-1,1-glucoside of malto-oligosyltrehalose and short-chain sugar molecules such as mannitol (C6H14O6), respectively. In this research, finding the associated expression proteins which is involved in changing the pathway of gluconeogenesis shift to PHA synthesis will be useful information on genetically modifying microorganisms to produce PHA more efficiently, leading to reduction of the production costs.

scholarly journals A Review of the Applications, Environmental Release, and Remediation Technologies of Per- and Polyfluoroalkyl Substances

2020 ◽  
Vol 17 (21) ◽  
pp. 8117
Author(s):  
Jay N. Meegoda ◽  
Jitendra A. Kewalramani ◽  
Brian Li ◽  
Richard W. Marsh
Keyword(s):  
Emerging Technologies ◽  
Industrial Applications ◽  
Consumer Products ◽  
The Body ◽  
Environmental Matrices ◽  
Considerable Uncertainty ◽  
Regulatory Standards ◽  
Treatment Train ◽  
Polyfluoroalkyl Substances ◽  
The Impact

Per- and polyfluoroalkyl substances (PFAS) are pollutants that have demonstrated a high level of environmental persistence and are very difficult to remediate. As the body of literature on their environmental effects has increased, so has regulatory and research scrutiny. The widespread usage of PFAS in industrial applications and consumer products, complicated by their environmental release, mobility, fate, and transport, have resulted in multiple exposure routes for humans. Furthermore, low screening levels and stringent regulatory standards that vary by state introduce considerable uncertainty and potential costs in the environmental management of PFAS. The recalcitrant nature of PFAS render their removal difficult, but existing and emerging technologies can be leveraged to destroy or sequester PFAS in a variety of environmental matrices. Additionally, new research on PFAS remediation technologies has emerged to address the efficiency, costs, and other shortcomings of existing remediation methods. Further research on the impact of field parameters such as secondary water quality effects, the presence of co-contaminants and emerging PFAS, reaction mechanisms, defluorination yields, and the decomposition products of treatment technologies is needed to fully evaluate these emerging technologies, and industry attention should focus on treatment train approaches to improve efficiency and reduce the cost of treatment.

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