Enzymatic isolation
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Yeasts are unicellular fungi that occur in a wide range of ecological niches, where they perform numerous functions. Furthermore, these microorganisms are used in industrial processes, food production, and bioremediation. Understanding the physiological and adaptive characteristics of yeasts is of great importance from ecological, biotechnological, and industrial perspectives. In this context, we evaluated the abilities to assimilate and ferment different carbon sources, to produce extracellular hydrolytic enzymes, and to tolerate salt stress, heavy metal stress, and UV-C radiation of two isolates of Eremothecium coryli, isolated from Momordica indica fruits. The two isolates were molecularly identified based on sequencing of the 18S-ITS1-5.8S-ITS2 region. Our isolates were able to assimilate nine carbon sources (dextrose, galactose, mannose, cellobiose, lactose, maltose, sucrose, melezitose, and pectin) and ferment three (glucose, maltose, and sucrose). The highest values of cellular dry weight were observed in the sugars maltose, sucrose, and melezitose. We observed the presence of hyphae and pseudohyphae in all assimilated carbon sources. The two isolates were also capable of producing amylase, catalase, pectinase, and proteases, with the highest values of enzymatic activity found in amylase. Furthermore, the two isolates were able to grow in media supplemented with copper, iron, manganese, nickel, and zinc and to tolerate saline stress in media supplemented with 5% NaCl. However, we observed a decrease in CFU at higher concentrations of these metals and NaCl. We also observed morphological changes in the presence of metals, which include changes in cell shape and cellular dimorphisms. The isolates were sensitive to UV-C radiation in the shortest exposure time (1 min). Our findings reinforce the importance of endophytic yeasts for biotechnological and industrial applications and also help to understand how these microorganisms respond to environmental variations caused by human activities.
- MeSH
- endofyty * izolace a purifikace genetika metabolismus fyziologie klasifikace účinky záření MeSH
- fermentace MeSH
- fylogeneze MeSH
- fyziologický stres * MeSH
- metabolismus sacharidů * MeSH
- ovoce * mikrobiologie MeSH
- Saccharomycetales * izolace a purifikace genetika fyziologie metabolismus účinky záření klasifikace MeSH
- těžké kovy toxicita MeSH
- ultrafialové záření MeSH
- Publikační typ
- časopisecké články MeSH
Cellular processes such as tissue regeneration, inflammation, and migration require the proteolysis of the extracellular matrix and the proteolytic activation of signaling molecules. A widely used and accessible technique for studying these processes is gelatin zymography, particularly for investigating matrix metalloproteinases (MMPs), though it is not limited to them. This method is favored for its simplicity, low cost, and robustness. Despite certain limitations, it remains a preferred approach for the initial investigation of complex samples.Here, we present a protocol applicable to various sample sources, including proteases from human cell lines and bacteria isolated from chronic wounds. We also explore changes in protease activity within exudates from human chronic wounds, a challenging analysis for more complex techniques. Additionally, we emphasize the potential to extend the basic protocol to study the conditions under which proteases are active.
Bioethanol production from lignocellulosic materials is hindered by the high costs of pretreatment and the enzymes. The present study aimed to evaluate whether co-cultivation of four selected cellulolytic fungi yields higher cellulase and xylanase activities compared to the monocultures and to investigate whether the enzymes from the co-cultures yield higher saccharification on selected plant materials without thermo-chemical pretreatment. The fungal isolates, Trichoderma reesei F118, Penicillium javanicum FS7, Talaromyces sp. F113, and Talaromyces pinophilus FM9, were grown as monocultures and binary co-cultures under submerged conditions for 7 days. The cellulase and xylanase activities of the culture filtrates were measured, and the culture filtrates were employed for the saccharification of sugarcane leaves, Guinea grass leaves, and water hyacinth stems and leaves. Total reducing sugars and individual sugars released from each plant material were quantified. The co-culture of Talaromyces sp. F113 with Penicillium javanicum FS7 and of T. reesei F118 with T. pinophilus FM9 produced significantly higher cellulase activities compared to the corresponding monocultures whereas no effect was observed on xylanase activities. Overall, the highest amounts of total reducing sugars and individual sugars were obtained from Guinea grass leaves saccharified with the co-culture of T. reesei F118 with T. pinophilus FM9, yielding 63.5% saccharification. Guinea grass leaves were found to be the most susceptible to enzymatic saccharification without pre-treatment, while water hyacinth stems and leaves were the least. Accordingly, the study suggests that fungal co-cultivation could be a promising approach for the saccharification of lignocellulosic materials for bioethanol production.
- MeSH
- celulasa * metabolismus MeSH
- endo-1,4-beta-xylanasy metabolismus MeSH
- ethanol metabolismus MeSH
- Hypocreales enzymologie metabolismus růst a vývoj MeSH
- kokultivační techniky * MeSH
- lignin * metabolismus MeSH
- listy rostlin mikrobiologie MeSH
- Penicillium * enzymologie metabolismus růst a vývoj MeSH
- Saccharum * mikrobiologie metabolismus MeSH
- Talaromyces * enzymologie metabolismus růst a vývoj MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Data from surveillance on antibiotic resistance have shown an increasing prevalence of non-enzymatic resistance (β-lactamase-negative ampicillin-resistant) to β-lactam antibiotics among H. influenzae strains in the Czech Republic. Aminopenicillins are recommended agents for non-invasive Haemophilus influenzae infections. The phenomenon of non-enzymatic resistance to β-lactams is complicated by the fact that the phenotypic detection of PBP3 with specific amino acid substitutions (rPBP3) is challenging, since rPBP3 isolates have repeatedly been demonstrated to be split by the epidemiological cut-off values (ECOFF) for aminopenicillins defined by EUCAST. OBJECTIVES: We sought to determine whether the penicillin disc has sufficient detection ability to predict the non-enzymatic mechanism; whether other antibiotics can be used for detection; and what is the agreement between the broth microdilution and disc diffusion methods. METHODS: We undertook susceptibility testing of selected antibiotics according to EUCAST of 153 rPBP3 strains, and sequencing of the ftsI gene to determination amino acid substitutions. RESULTS: For a selected set of rPBP strains: (i) the detection capability for penicillin, ampicillin, cefuroxime and amoxicillin/clavulanate was found to be 91.5%, 94.4%, 89.5% and 70.6%, respectively; (ii) the categorical agreement between the disc diffusion method and the MIC for ampicillin and cefuroxime was 71.1% and 83.8%, respectively. CONCLUSIONS: We observed better recognition of rPBP3 strains by the ampicillin disc than by the penicillin disc. There is frequently a discrepancy in the interpretation of susceptibility results between the methods used.
- MeSH
- antibakteriální látky * farmakologie MeSH
- bakteriální proteiny * genetika MeSH
- beta-laktamová rezistence * MeSH
- beta-laktamy * farmakologie MeSH
- fenotyp MeSH
- Haemophilus influenzae * účinky léků genetika izolace a purifikace enzymologie MeSH
- hemofilové infekce mikrobiologie MeSH
- lidé MeSH
- mikrobiální testy citlivosti metody MeSH
- proteiny vázající penicilin * genetika MeSH
- sekvenční analýza DNA MeSH
- substituce aminokyselin * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
Aminophylline, a bronchodilator mainly used to treat severe asthma attacks, may induce arrhythmias. Unfortunately, the underlying mechanism is not well understood. We have recently described a significant, on average inhibitory effect of aminophylline on inward rectifier potassium current IK1, known to substantially contribute to arrhythmogenesis, in rat ventricular myocytes at room temperature. This study was aimed to examine whether a similar effect may be observed under clinically relevant conditions. Experiments were performed using the whole cell patch clamp technique at 37°C on enzymatically isolated healthy porcine and failing human ventricular myocytes. The effect of clinically relevant concentrations of aminophylline (10-100 μM) on IK1 did not significantly differ in healthy porcine and failing human ventricular myocytes. IK1 was reversibly inhibited by ∼20 and 30 % in the presence of 30 and 100 μM aminophylline, respectively, at -110 mV; an analogical effect was observed at -50 mV. To separate the impact of IK1 changes on AP configuration, potentially interfering ionic currents were blocked (L-type calcium and delayed rectifier potassium currents). A significant prolongation of AP duration was observed in the presence of 100 μM aminophylline in porcine cardiomyocytes which well agreed with the effect of a specific IK1 inhibitor Ba2+ (10 μM) and with the result of simulations using a porcine ventricular cell model. We conclude that the observed effect of aminophylline on healthy porcine and failing human IK1 might be involved in its proarrhythmic action. To fully understand the underlying mechanism, potential aminophylline impact on other ionic currents should be explored.
- MeSH
- akční potenciály účinky léků MeSH
- aminofylin * farmakologie MeSH
- draslíkové kanály dovnitř usměrňující * metabolismus MeSH
- kardiomyocyty * účinky léků metabolismus MeSH
- lidé MeSH
- metoda terčíkového zámku MeSH
- prasata MeSH
- srdeční komory účinky léků metabolismus MeSH
- srdeční selhání metabolismus farmakoterapie MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Citrulline is a non-proteinogenic amino acid that forms as by-product in nitric oxide (NO) synthesis from arginine and may act in concert with NO as an independent signaling molecule that involves in the mechanism of vascular smooth muscle vasodilation. In this study we examined the effects of citrulline on pulmonary artery smooth muscles. Experimental design comprised outward potassium currents measurements in enzymatically isolated rat pulmonary artery smooth muscle (PASMc) cells using whole-cell patch clamp technique, isometric contractile force recordings on rat pulmonary artery rings and method of molecular docking simulation. Citrulline in a concentration 10-9-10-5 M relaxed phenylephrine (PHE)-preactivated SM of rat pulmonary artery in a dose-dependent manner (EC50 0,67 μM). This citrulline-induced relaxation was dependent on an intact endothelium. Bath application of citrulline (10-8-10-5 M) on isolated PASMc induced a significant increase in the amplitude of outward potassium current (Ik). The adenosine antagonist caffeine (10-6 M) effectively blocked both the citrulline-induced relaxation response and Ik increment. Molecular docking modeling suggests that caffeine blocking the potent activity of citrulline results from competitive interactions at the A2 adenosine receptor binding site. In summary, our data suggest that citrulline, released with NO at low concentrations, can effectively interact with adenosine receptors in smooth muscle cells, causing their relaxation, indicating surprising interaction between NO and adenosine pathways.
- MeSH
- arteria pulmonalis účinky léků metabolismus MeSH
- citrulin * farmakologie metabolismus MeSH
- krysa rodu rattus MeSH
- potkani Wistar MeSH
- purinergní receptory P1 metabolismus MeSH
- simulace molekulového dockingu * MeSH
- svaly hladké cévní metabolismus účinky léků MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Innovative approaches to controlled nucleobase-modified RNA synthesis are urgently needed to support RNA biology exploration and to synthesize potential RNA therapeutics. Here we present a strategy for enzymatic construction of nucleobase-modified RNA based on primer-dependent engineered thermophilic DNA polymerases - SFM4-3 and TGK. We demonstrate introduction of one or several different base-modified nucleotides in one strand including hypermodified RNA containing all four modified nucleotides bearing four different substituents, as well as strategy for primer segment removal. We also show facile site-specific or segmented introduction of fluorophores or other functional groups at defined positions in variety of RNA molecules, including structured or long mRNA. Intriguing translation efficacy of single-site modified mRNAs underscores the necessity to study isolated modifications placed at designer positions to disentangle their biological effects and enable development of improved mRNA therapeutics. Our toolbox paves the way for more precise dissecting RNA structures and functions, as well as for construction of diverse types of base-functionalized RNA for therapeutic applications and diagnostics.
- MeSH
- DNA-dependentní DNA-polymerasy * genetika MeSH
- messenger RNA genetika MeSH
- nukleotidy chemie MeSH
- RNA * genetika chemie MeSH
- Publikační typ
- časopisecké články MeSH
Numerous functions in pathogenic Pectobacterium are regulated by quorum sensing (QS). Two different aiiA genes isolated from Bacillus sp. A24(aiiAA24) and Bacillus sp. DMS133(aiiADMS133) were used. Both genes encode acyl-homoserine lactonase (AiiA), which disrupts QS in Pectobacterium. To investigate the effect of different AiiAs on the inhibition of Pectobacterium carotovorum pathogenicity, two aiiA genes from different Bacillus strains were cloned and the resulting plasmids pME6863 (aiiAA24) and pME7080 (aiiADMS133) were transformed into P. carotovorum EMPCC cells. The effects of different lactonases on virulence features such as enzymatic activity, twitching and swimming motilities, and production of pellicle and biofilm formation were investigated. In EMPCC/pME6863, twitching and swimming motilities, and pellicle production were significantly reduced compared with EMPCC/pME7080. Quantitative real-time PCR (qRT-PCR) was used to measure virulence gene expression in transformed cells compared with expression levels in wild-type EMPCC. The expression of peh and hrpL genes was greatly reduced in EMPCC/pME6863 compared with EMPCC/pME7080. The sequence alignment and molecular dynamic modeling of two different AiiAA24 and AiiADMS133 proteins suggested that the replacement of proline 210 from AiiAA24 to serine in AiiADMS133 caused the reduction of enzyme activity in AiiADMS133.
- MeSH
- Bacillus * genetika enzymologie MeSH
- bakteriální proteiny * genetika metabolismus MeSH
- biofilmy růst a vývoj MeSH
- karboxylesterhydrolasy * genetika metabolismus MeSH
- klonování DNA MeSH
- metaloendopeptidasy MeSH
- Pectobacterium carotovorum genetika enzymologie patogenita MeSH
- quorum sensing * MeSH
- regulace genové exprese u bakterií MeSH
- virulence MeSH
- Publikační typ
- časopisecké články MeSH
Oxalate degradation is one of lactic acid bacteria's desirable activities. It is achieved by two enzymes, formyl coenzyme A transferase (frc) and oxalyl coenzyme A decarboxylase (oxc). The current study aimed to screen 15 locally isolated lactic acid bacteria to select those with the highest oxalate degradation ability. It also aimed to amplify the genes involved in degradation. MRS broth supplemented with 20 mM sodium oxalate was used to culture the tested isolates for 72 h. This was followed by an enzymatic assay to detect remaining oxalate. All isolates showed oxalate degradation activity to variable degrees. Five isolates demonstrated high oxalate degradation, 78 to 88%. To investigate the oxalate-degradation potential of the selected isolates, they have been further tested for the presence of genes that encode for enzymes involved in oxalate catabolism, formyl coenzyme A transferase (frc) and oxalyl coenzyme A decarboxylase (oxc). Three strains showed bands with the specific OXC and FRC forward and reverse primers designated as (SA-5, 9 and 37). Species-level identification revealed Loigolactobacillus bifermentans, Lacticaseibacillus paracasei, and Lactiplantibacillus plantarum. Preliminary results revealed that the tested probiotic strains harbored both oxc and frc whose products are putatively involved in oxalate catabolism. The probiotic potential of the selected strains was evaluated, and they showed high survival rates to both simulated gastric and intestinal fluids and variable degrees of antagonism against the tested Gram-positive and negative pathogens and were sensitive to clarithromycin but resistant to both metronidazole and ceftazidime. Finally, these strains could be exploited as an innovative approach to establish oxalate homeostasis in humans and prevent kidney stone formation.
- MeSH
- acylkoenzym A * MeSH
- CoA-transferasy genetika metabolismus MeSH
- karboxylyasy * genetika MeSH
- lidé MeSH
- oxaláty metabolismus MeSH
- probiotika * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Only a few studies dealt with the occurrence of endospore-forming clostridia in the microbiota of infants without obvious health complications. METHODS: A methodology pipeline was developed to determine the occurrence of endospore formers in infant feces. Twenty-four fecal samples (FS) were collected from one infant in monthly intervals and were subjected to variable chemical and heat treatment in combination with culture-dependent analysis. Isolates were identified by MALDI-TOF mass spectrometry, 16S rRNA gene sequencing, and characterized with biochemical assays. RESULTS: More than 800 isolates were obtained, and a total of 21 Eubacteriales taxa belonging to the Clostridiaceae, Lachnospiraceae, Oscillospiraceae, and Peptostreptococcaceae families were detected. Clostridium perfringens, C. paraputrificum, C. tertium, C. symbiosum, C. butyricum, and C. ramosum were the most frequently identified species compared to the rarely detected Enterocloster bolteae, C. baratii, and C. jeddahense. Furthermore, the methodology enabled the subsequent cultivation of less frequently detectable gut taxa such as Flavonifractor plautii, Intestinibacter bartlettii, Eisenbergiella tayi, and Eubacterium tenue. The isolates showed phenotypic variability regarding enzymatic activity, fermentation profiles, and butyrate production. CONCLUSIONS: Taken together, this approach suggests and challenges a cultivation-based pipeline that allows the investigation of the population of endospore formers in complex ecosystems such as the human gastrointestinal tract.
- MeSH
- Clostridium * genetika MeSH
- feces mikrobiologie MeSH
- Firmicutes genetika MeSH
- kojenec MeSH
- lidé MeSH
- mikrobiota * MeSH
- RNA ribozomální 16S genetika MeSH
- Check Tag
- kojenec MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH