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Wyniki wyszukiwania dla: e. coli
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Źródła, otrzymywanie i przydatność niektórych termostabilnych enzymów w przetwórstwie skrobi i mleka
PublikacjaPrezentowane wyniki wskazują na możliwość usprawnienia produkcji syropów skrobiowych przez zastosowanie rekombinantowej alfa-amylazy z Pyrococcus woesei i termostabilnej alfa-glukozydazy z Thermus thermophilus. Wykazano także przydatność rekombinantowej, termosta-bilnej beta-galaktozydazy z Pyrococcus woesei do wytwarzania bez-laktozowego mleka i serwatki. Enzym ten wykazuje dużą termostabil-ność i znaczną aktywność w szerokim...
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A new MIC1-MAG1 recombinant chimeric antigen can be used instead of the Toxoplasma lysate antigen in the serodiagnosis of human toxoplasmosis
PublikacjaW niniejszej publikacji po raz pierwszy przedstawiono otrzymanie i oszacowanie przydatności diagnostycznej nowego chimerycznego antygenu MIC1-MAG1 Toxoplasma gondii do rozpoznawania toksoplazmozy u ludzi. Antygen chimeryczny MIC1-MAG1 został otrzymany jako białko fuzyjne zawierające dwie domeny oligohistydynowe na N- i C-końcu z użyciem systemu ekspresyjnego Escherichia coli. Po oczyszczeniu z wykorzystaniem metody chromatografii...
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Organizmy obecne w osadzie dennym basenów kąpielowych
PublikacjaMonitorowanie parametrów wody basenowej jest istotne z uwagi na zdrowie osób korzystających z basenu jak i pracowników obsługi. Istnieją trzy źródła materii organicznej: woda dostarczona do basenu, pasywne zanieczyszczenia wnoszone przez osoby kąpiące się oraz zanieczyszczenia organiczne w postaci moczu i kału. Jakość wody w basenach powinna być porównywalna do jakości wody pitnej. Jakość mikrobiologiczna opiera się na tradycyjnych...
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Characterization of recombinant homocitrate synthase from Candida albicans
PublikacjaLYS21 and LYS22 genes from Candida albicans encoding isoforms of homocitrate synthase (HCS), an enzyme catalyzing the first committed step in the L-lysine biosynthetic pathway, were cloned and expressed as NoligoHistagged fusion proteins in Escherichia coli. The purified gene products revealed HCS activity, i.e. catalyzed the condensation of α-ketoglutarate with acetyl-coenzyme A to yield homocitrate. The recombinant enzymes were purified...
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Assembly of Lipopolysaccharide in Escherichia coli Requires the Essential LapB Heat Shock Protein
PublikacjaHere, we describe two new heat shock proteins involved in the assembly of LPS in Escherichia coli, LapA and LapB (lipopolysaccharide assembly protein A and B). lapB mutants were identified based on an increased envelope stress response. Envelope stress responsive pathways control key steps in LPS biogenesis and respond to defects in the LPS assembly. Accordingly, the LPS content in ΔlapB or Δ(lapA lapB) mutants was elevated, with...
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Identification and characterization of single-stranded DNA-binding protein from the facultative psychrophilic bacteria Pseudoalteromonas haloplanktis
PublikacjaSingle-stranded DNA-binding protein (SSB) plays an important role in DNA metabolism such as DNAreplication, repair, and recombination, and is essential for cell survival. This study reports on the ssb-likegene cloning, gene expression and characterization of a single-stranded DNA-binding protein of Pseudoal-teromonas haloplanktis (PhaSSB) and is the first report of such a protein from psychrophilic microorganism.PhaSSB possesses...
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Electrochemical detection of bacterial endotoxin lipopolysaccharide (LPS) on gold electrode modified with DAL-PEG-DK5-PEG-OH - Antimicrobial peptide conjugate
PublikacjaThis work describes fabrication of gold electrodes modified with peptide conjugate DAL-PEG-DK5-PEG-OH that enables ultra-sensitive detection of lipopolysaccharide (LPS) isolated from the reference strain of Escherichia coli O26:B6. The initial step of the established procedure implies immobilization of the fully protected DAL-PEG-DK5-PEG-OH peptide on the surface of the gold electrode previously modified by cysteamine. Then side...
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Defected Ag/Cu-MOF as a modifier of polyethersulfone membranes for enhancing permeability, antifouling properties and heavy metal and dye pollutant removal
PublikacjaIn this study, a novel bimetallic metal-organic framework (MOF) i.e. Ag/Cu-MOF was synthesized using a solvothermal method and later incorporated at different concentrations (0.1–2 wt%) using a phase inversion method for modification and antifouling property improvement of polyethersulfone (PES) membranes. The resulting Ag/Cu-MOF characteristics were investigated using different techniques, such as FTIR, XRD, FE-SEM and EDX. The...
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Multiple transcriptional factors regulate transcription of the rpoE gene in Escherichia coli under different growth conditions and when the lipopolysaccharide biosynthesis is defective.
PublikacjaThe RpoE sigma factor is essential for the viability of Escherichia coli. RpoE regulates extracytoplasmic functions including lipopolysaccharide (LPS) translocation and some of its non-stoichiometric modifications. Transcription of the rpoE gene is positively autoregulated by EσE and by unknown mechanisms that control the expression of its distally located promoter(s). Mapping of 5′ ends of rpoE mRNA identified five new transcriptional...
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High prevalence of Escherichia coli belonging to the B2+D phylogenetic group in inflammatory bowel disease
PublikacjaBACKGROUND: It is not clear which species of bacteria may be involved in inflammatory bowel disease (IBD). One way of determining which bacteria might be likely candidates is to use culture-independent methods to identify microorganisms that are present in diseased tissues but not in controls. AIMS: (1) To assess the diversity of microbial communities of biopsy tissue using culture-independent methods; (2) to culture the bacteria...
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Toxoplasma gondii: Enzyme-Linked Immunosorbent Assay using different fragments of recombinant microneme protein 1 (MIC1) for detection of immunoglobulin G antibodies
PublikacjaTrzy rekombinantowe fragmenty białka antygenowego MIC1 Toxoplasma gondii (r-MIC1ex2, r-MIC1ex34 i r-MIC1) zostały wyprodukowane jako białka fuzyjne (zawierające dwie domeny oligohistydynowe na N- i C-końcu) w komórkach bakteryjnych Escherichia coli. Homogenne preparaty antygenów rekombinantowych otrzymane z zastosowaniem jednoetapowego oczyszczania metodą chromatografii metalopowinowactwa, wykorzystano następnie do immunoidentyfikacji...
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THE GENE CLONING, OVEREXPRESSION, PURIFICATION AND BIOCHEMICAL CHARACTERISATION OF A NEW COLD-ADAPTED β–GALACTOSIDASE FROM ARTHROBACTER SP. VII-4
PublikacjaINTRODUCTION. β-Galactosidase [EC 3.2.1.23] is an enzyme that catalyzes the hydrolysis of O-glycosidic linkages in galactosides. It is commercially used in dairy industry for the production of milk with reduced lactose content. Potentially, the best method for lactose removal under cooling conditions should be carried out with a cold-adapted enzyme. AIM. The aim of this study was to determine the taxonomic affiliation of the isolate...
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B-GALACTOSIDASE ARTHROBACTER SP. 32cB - OBTAINING THE GENE SEQUENCE, CONSTRUCTION OF THE EXPRESSION SYSTEM, BIOSYNTHESIS AND BIOCHEMICAL CHARACTERIZATION OF THE ENZYME
PublikacjaINTRODUCTION: β-Galactosidase is an enzyme which catalyzes the hydrolysis of O glycosidic bond in β-galactosides. Another activity of β galactosidase is a transglycosylation activity. The main industrial use of this protein is the hydrolysis of lactose in milk in a cooling conditions. Synthesis of galactooligosaccharides, which are mostly used as a prebiotics added to some foods or available as dietary supplements, is only one...
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Characterization of a single-stranded DNA-binding-like Protein from Nanoarchaeum equitans - a nucleic acid binding protein with broad substrate specificity
PublikacjaBackground SSB (single-stranded DNA-binding) proteins play an essential role in all living cells and viruses, as they are involved in processes connected with ssDNA metabolism. There has recently been an increasing interest in SSBs, since they can be applied in molecular biology techniques and analytical methods. Nanoarchaeum equitans, the only known representative of Archaea phylum Nanoarchaeota, is a hyperthermophilic, nanosized,...
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Molecular basis of lipopolysaccharide heterogeneity in Escherichia coli: envelope stress-responsive regulators control the incorporation of glycoforms with a third 3-deoxy-α-D-manno-oct-2-ulosonic acid and rhamnose.
PublikacjaMass spectrometric analyses of lipopolysaccharide (LPS) from isogenic Escherichia coli strains with nonpolar mutations in the waa locus or overexpression of their cognate genes revealed that waaZ and waaS are the structural genes required for the incorporation of the third 3-deoxy-α-D-manno-oct-2-ulosonic acid (Kdo) linked to Kdo disaccharide and rhamnose, respectively. The incorporation of rhamnose requires prior sequential incorporation...
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Bioactivation of Konjac Glucomannan Films by Tannic Acid and Gluconolactone Addition
PublikacjaWound healing is a dynamic process that requires an optimal extracellular environment, as well as an accurate synchronization between various cell types. Over the past few years, great efforts have been devoted to developing novel approaches for treating and managing burn injuries, sepsis, and chronic or accidental skin injuries. Multifunctional smart-polymer-based dressings represent a promising approach to support natural healing...
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Structural studies of a cold-adapted dimeric Beta-D-galactosidase from Paracoccus sp. 32d
PublikacjaThe crystal structure of a novel dimeric [beta]-D-galactosidase from Paracoccus sp. 32d (Par[beta]DG) was solved in space group P212121 at a resolution of 2.4 Å by molecular replacement with multiple models using the BALBES software. This enzyme belongs to glycoside hydrolase family 2 (GH2), similar to the tetrameric and hexameric [beta]-D-galactosidases from Escherichia coli and Arthrobacter sp. C2-2, respectively. It is the second...
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Lipopolysaccharides: regulated biosynthesis and structural diversity
PublikacjaThe cell envelope of Gram-negative bacteria contains two distinct membranes, an inner (IM) and an outer (OM) membrane, separated by the periplasm, a hydrophilic compartment that includes a thin layer of peptidoglycan. The most distinguishing feature of such bacteria is the presence of an asymmetric OM with phospholipids located in the inner leaflet and lipopolysaccharides (LPSs) facing the outer leaflet. The maintenance of this...
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Possibility of Using Tea Fungus for Fermentation of Beetroot and Carrot Pomace Beverages
PublikacjaFermented beverages obtained from plant-based raw materials are becoming more popular due to their beneficial effects on human health. These include kombucha beverages, which are obtained by fermenting tea brew using the so-called tea fungus, which includes acetic acid bacteria and osmophilic yeast. A consortium of these microorganisms could also be used to prepare functional fermented beverages obtained from extracts of vegetable...
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A two-plasmid Escherichia coli system for expression of Dr adhesins
PublikacjaPraca opisuje konstrukcję wydajnego systemu produkcji fimbrii Dr. System składa się z dwóch plazmidów. Plazmid pACYCpBAD-DraC-C-His zawiera pod kontrolą promotora arabinozowego gen draC kodujący białko kanałotwórcze DraC. Plazmid pET-30b-sygDraBE zawiera pod kontrolą promotora T7lac geny draB i draE kodujące odpowiednio białko opiekuńcze DraB oraz adhezynę DraE. Oba plzamidy posiadają różne ori replikacji co pozwala na ich jednoczesne...
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Preclusion of irreversible destruction of Dr adhesin structures by a high activation barrier for the unfolding stage of the fimbrial DraE subunit
PublikacjaFimbrie Dr uropatogennych szczepów Escherichia coli stanowią przykład eksponowanych powierzchniowo struktur adhezyjnych podlegających biogenezie według zakonserwowanego, pośród bakterii Gram-ujemnych, systemu "chaperone-usher" ("białko opiekuńcze-zewnątrzbłonowe białko kanałowe"). Powyższe struktury adhezyjne są niezbędne w procesie specyficznej adhezji bakterii do receptorów zlokalizowanych na powierzchni docelowych komórek gospodarza....
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FUNKCJONALIZOWANIE 2H-TIAZOLO[3,2-α]PIRYDYN-5-(3H)-ONÓW, ALTERNATYWNA ŚCIEŻKA SYNTEZY NOWYCH PILICYDÓW
PublikacjaUropatogenne szczepy Escherichia coli są przyczyną blisko 80% przypadków zakażeń dróg moczowych (ang. UTI- Urinary tract infection). Ponadto, aż 30% odmiedniczkowego zapalenia nerek występującego u ciężarnych kobiet jest spowodowane przez szczepy E.coli Dr+. Szerząca się lekooporność bakterii i trudności w leczeniu UTI wymusiły na środowiskach naukowych poszukiwania nowych związków chemicznych pełniących rolę chemoterapeutyków. Na...
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MutS3: a MutS homologue of unknown biological function
PublikacjaThe homologues of MutS proteins are widespread among both Prokaryotes and Eukaryotes. MutS designated as MutS1 is a part of MMR (mismatch repair) system which is responsible for removal of mispaired bases and small insertion/deletion loops in DNA. Initially, the only MutS homologues known were those engaged in mismatch repair and these were later designated as MutS1. Subsequently, the MutS2 homologue was distinguished. MutS2 does...
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Regulation of LPS assembly via controlled proteolysis and sensing of LPS stress in Escherichia coli
PublikacjaLipopolysaccharide (LPS) is a complex glycolipid, essential for the bacterial viability and along with phospholipids, it constitutes the major amphiphilic component of outer membrane (OM) in most of the Gram-negative bacteria, including Escherichia coli. LPS molecules confer an effective permeability barrier to the OM and play a crucial role in bacteria-environment and -host interactions. The synthesis and accumulation of this...
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Structural analogues of reactive intermediates as inhibitors of glucosamine-6-phosphate synthase and phosphoglucose isomerase
PublikacjaCentra aktywne izomerazy fosfoglukozowej (PGI) oraz domeny izomerazowej (HPI) syntazy glukozamino-6-fosforanu (GlcN-6-P), wykazują podobieństwo ułożenia przestrzennego kluczowych reszt aminokwasowych, z wyjątkiem reszty Arg272 PGI i reszt Lys603 i Lys485 HPI. Dziesięć pochodnych D-heksitolo-6-P, kwasu 5-fosfoarabonowego i kwasu 6-fosfoglukonowego, strukturalnych analogów cis-enolaminy lub cis-enolanu, przypuszczalnych stanów przejściowych...
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A method for the production of D-tagatose using a recombinant Pichia pastoris strain secreting beta-D-galactosidase from Arthrobacter chlorophenolicus and a recombinant L-arabinose isomerase from Arthrobacter sp. 22c
PublikacjaD-Tagatose is a natural monosaccharide which can be used as a low-calorie sugar substitute in food, beverages and pharmaceutical products. It is also currently being tested as an anti-diabetic and obesity control drug. D-Tagatose is a rare sugar, but it can be manufactured by the chemical or enzymatic isomerization of D-galactose obtained by a beta-D-galactosidase-catalyzed hydrolysis of milk sugar lactose and the separation of...