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Wyniki wyszukiwania dla: BACTERAEMIA BOWEL TRANSLOCATION ESCHERICHIA COLI LEUKAEMIA VIRULENCE FACTORS
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Characterisation of Escherichia coli isolates from the blood of haematological adult patients with bacteraemia: translocation from gut to blood requires the cooperation of multiple virulence factors
PublikacjaThe aim of the study was to investigate whether there are unique pathotypes of Escherichia coli capable of transmission from the gastrointestinal tract to the vascular bed. The study included E. coli strains isolated from clinical materials collected from 115 patients suffering from haematologic malignancies diagnosed with bacteraemia. The genotyping techniques established that 89 E. coli isolates from the blood had the same genotype...
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Recurrent bowel-blood translocations of Escherichia coli with the unique virulence characteristics over three-year period in the patient with acute myeloid leukaemia – case report
PublikacjaIn patients with haematological malignancies, the bowel remains the main source of Escherichia coli bloodstream infections. We present the clinical example of recurrent bowel-blood translocations of E. coli with the unique virulence characteristics in a 55-year-old male with the diagnosis of acute myeloid leukaemia. The virulent factors profile of examined strains confirmed that the co-existence of genes papC, sfa, usp and cnf1,...
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Leukemia and risk of recurrent Escherichia coli bacteremia: genotyping implicates E. coli translocation from the colon to the bloodstream.
PublikacjaIn patients with leukemia, the portal(s) and reasons for the persistence of an Escherichia coli recurrent bacteremia remain unclear. Adult Hematology Clinic (AHC) databases at the State Clinical Hospital in Gdańsk were reviewed to evaluate the frequency of E. coli bacteremia between 2002 and 2005. Blood and bowel E. coli strains were obtained and the genetic relatedness of the strains was analyzed. The rate of E. coli bacteremia...
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A subset of two adherence systems, acute pro-inflammatory pap genes and invasion coding dra, fim, or sfa, increases the risk of Escherichia coli translocation to the bloodstream
PublikacjaAn analysis of the phylogenetic distribution and virulence genes of Escherichia coli isolates which predispose this bacteria to translocate from the urinary tract to the bloodstream is presented. One-dimensional analysis indicated that the occurrence of P fimbriae and α-hemolysin coding genes is more frequent among the E. coli which cause bacteremia. However, a two-dimensional analysis revealed that a combination of genes coding...
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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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Regulated Assembly of LPS, Its Structural Alterations and Cellular Response to LPS Defects
PublikacjaDistinguishing feature of the outer membrane (OM) of Gram-negative bacteria is its asymmetry due to the presence of lipopolysaccharide (LPS) in the outer leaflet of the OM and phospholipids in the inner leaflet. Recent studies have revealed the existence of regulatory controls that ensure a balanced biosynthesis of LPS and phospholipids, both of which are essential for bacterial viability. LPS provides the essential permeability...
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Enzymatic degradation and transport of endothiopeptides into Escherichia coli K12 mutant strains
PublikacjaZbadano transport trzech otrzymanych na drodze syntezy ditiopeptydów do komórek Escherichia coli K12. Ponadto zbadano szybkość hydrolizy tych związków. Wszystkie peptydy są transportowane przez permeazy, natomiast są bardziej oporne na hydrolizę enzymatyczną w stosunku do naturalnych peptydów.
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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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Genotyping and characterization of virulence factors in Escherichia coli strains isolated from patients from Polish hospital
PublikacjaZakażenia układu moczowego (UTIs - ang. urinary track infections) są jedną z najczęstszy infekcji, za które w 85% przypadków odpowiedzialne są bakterie Escherichia coli. Infekcje układu moczowego mogą prowadzić do groźnych powikłań m. in. odmiedniczkowego zapalenia nerek. Śmiertelność wśród tej grupy pacjentów wynosi 1-3%. Zakażenia układu moczowego występują również u ok. 7% kobiet ciężarnych. W pracy przebadano 82 szczepy E....
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Biofilm formation as a virulence determinant of uropathogenic Escherichia coli Dr+ strains
PublikacjaInfekcje dróg moczowych stanowią największy problem zdrowotny dotykający miliony osób populacji ludzkiej każdego roku. Uropatogenne szczepy Escherichia coli są najczęstszym czynnikiem etiologicznym odpowiedzialnym za wywoływanie górnych i dolnych dróg moczowych. Powyższe szczepy bakteryjne produkują szereg czynników wirulentnych pośród, których wyróżnić można eksponowane powierzchniowo polimeryczne struktury adhezyjne (fimbrie/pile)...
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Type II secretory pathway for surface secretion of DraD invasin from the uropathogenic Escherichia coli Dr+ strain
PublikacjaWłaściwości wirulentne uropatogennych szczepów Escherichia coli Dr+ IH11128 związane są z obecnością struktur fimbrialnych typu Dr i białka inwazyny DraD, które może na powierzchni komórki bakteryjnej pełnić rolę fimbrialnej podjednostki szczytowej. Ostatnie badania wykazały, że białko DraD jest eksponowane na powierzchni bakterii w dwóch formach: związanej ze strukturą fimbrialną i jako niezależna od fimbrii otoczka białkowa....
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A freeze-thaw method for desintegration of Escherichia coli cells producing T7 lysozyme used in pBAD expression systems
PublikacjaPlazmid pLysN zawierający gen kodujący lizozym T7 pod kontrolą promotora lac został skonstruowany w celu ułatwienia dezintegracji komórek po ekspresji rekombinantowych białek w systemach ekspresji indukowanych arabinozą. Użyteczność plazmidu została przetestowana w komórkach Escherichia coli TOP10 i E. coli LMG194, niosących plazmid pBADMHADgeSSB, zawierający gen kodujący białko SSB Deinococcus geothermalis pod kontrolą promotora...
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Molecular typing of clinical isolates of Escherichia coli by a new PCR MP method
PublikacjaTypowanie epidemiologiczne bakterii jest rutynową procedurą stosowaną w badaniach zakażeń szpitalnych i wymaga stosowania odpowiednich metod o wysokim potencjale różnicującym. Przedstawiliśmy możliwości nowej techniki PCR MP w różnicowaniu szczepów E. coli. Rezultaty zostały porównane z wynikami uzyskanymi metodą PFGE.
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Molecular typing of clinical isolates of Escherichia coli by a new PCR MP method
PublikacjaTypowanie epidemiologiczne bakterii jest rutynową procedurą stosowaną w badaniach zakażeń szpitalnych i wymaga stosowania odpowiednich metod o wysokim potencjale różnicującym. Przedstawiliśmy możliwości nowej techniki PCR MP w różnicowaniu szczepów E. coli. Rezultaty zostały porównane z wynikami uzyskanymi metodą PFGE.
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Antibiotic resistance, virulence, and phylogenetic analysis of Escherichia coli strains isolated from free-living birds in human habitats
PublikacjaWild birds can be colonized by bacteria, which are often resistant to antibiotics and have various virulence profiles. The aim of this study was to analyze antibiotic resistance mechanisms and virulence profiles in relation to the phylogenetic group of E. coli strains that were isolated from the GI tract of wildfowl. Out of 241 faecal samples, presence of E. coli resistant to a cephalosporin (ESBL/AmpC) was estimated for 33 isolates...
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Escherichia coli Strains with Virulent Factors Typical for Uropathogens were Isolated from Sinuses from Patients with Chronic Rhinosinusitis—Case Report
PublikacjaEscherichia coli were isolated from three patients with chronic rhinosinusitis (CRS) by intraoperative sinus tissue biopsy. Taking into account the unusual replicative niche and previous treatment failures, it was decided to focus on the virulence and drug resistance of these bacteria. The strains turned out to be multi-sensitive, but the rich virulence factors profile of bacteria typical for phylogenetic group B2 deserved attention....
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Biochemical characteristic of biofilm of uropathogenic Escherichia coli Dr+ strains.
PublikacjaUrinary tract infections caused by Escherichia coli are very common health problem in the developed countries. The virulence of the uropathogenic E. coli Dr+ IH11128 is determined by Dr fimbriae, which are homopolymeric structures composed of DraE subunits with the DraD protein capping the fiber. In this study, we have analyzed the structural and biochemical properties of biofilms developed by E. coli strains expressing Dr fimbriae...
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Beata Krawczyk dr hab.
Osobydr hab. Beata Krawczyk, prof. uczelni Stopnie naukowe, wykształcenie, kwalifikacje Beata Krawczyk uzyskała tytuł magistra biologii na Wydziale Biologii (wówczas: Wydział Biologii i Nauk o Ziemi), Uniwersytetu Gdańskiego w 1986 roku, a doktorat z biologii molekularnej na Wydziale Biologii (wówczas: Wydział Biologii, Geografii i Oceanologii) Uniwersytetu Gdańskiego w 1996 roku. Stopień doktora habilitowanego w zakresie nauk biologicznych...
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New Approaches for Escherichia coli Genotyping
PublikacjaEasy-to-perform, fast, and inexpensive methods of differentiation of Escherichia coli strains beyond the species level are highly required. Herein two new, original tools for genotyping of E. coli isolates are proposed. The first of the developed method, a PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) test uses a highly variable fliC gene, encoding the H antigen as a molecular target. The designing...
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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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Checkpoints that regulate balanced biosynthesis of lipopolysaccharide and its essentiality in Escherichia coli
PublikacjaThe outer membrane (OM) of Gram-negative bacteria, such as Escherichia coli, is essential for their viability. Lipopolysaccharide (LPS) constitutes the major component of OM, providing the permeability barrier, and a tight balance exists between LPS and phospholipids amounts as both of these essential components use a common metabolic precursor. Hence, checkpoints are in place, right from the regulation of the first committed step...
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Use of Escherichia coli Nissle 1917 producing recombinant colicins for treatment of IBD patients
PublikacjaPatients with Crohn’s Disease and ulcerative colitis infected with Adherent-Invasive Escherichia coli strains constitute the largest group among Inflammatory Bowel Disease subjects, when taking into account all known etiological agents of the disease. A possible link between these pathogenic bacteria and inflammation process has gained the confidence in recently published papers. Observed enteric neuroglial cells apoptosis and...
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Increased Levels of (p)ppGpp Correlate with Virulence and Biofilm Formation, but Not with Growth, in Strains of Uropathogenic Escherichia coli
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Alternative treatment approaches of urinary tract infections caused by uropathogenic Escherichia coli strains
PublikacjaUrinary tract infections (UTIs) are the most widespread and annoying infections affecting millions of people every year annually. The biggest problem of urinary diseases are recurrences, the increasing resistance of uropathogens to commonly used antibiotics, as well as the high health care costs of afflicted persons. Uropathogenic Escherichia coli strains (UPECs) are the most dominant etiologic agent of community-acquired infections...
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Phylogenetic relationship and antimicrobial resistance in Escherichia coli isolated from the Reda River and the Oliwski Stream, Northern Poland = Lekooporność i przynależność filogenetyczna szczepów Escherichia Coli izolowanych z rzeki Redy i Potoku Oliwskiego
PublikacjaThe high abundance of fecal bacteria in surface water is usually related to poor agricultural practice, pollution caused by domesticated and wild animals as well as with septic tank failures. Identification of fecal contamination sources seems to be crucial in order to effectively estimate the inherent risk. In this study, the phylogenetic relationship of 30 isolates of E. coli, originated from surface water, was estimated by employing...
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Influence of Escherichia coli on Expression of Selected Human Drug Addiction Genes
PublikacjaThe impact of enteric microflora on the expression of genes associated with cocaine and amphetamine addiction was described. Human genome-wide experiments on RNA transcripts expressed in response to three selected Escherichia coli strains allowed for significant alteration (p > 0.05) of the linear regression model between HT-29 RNA transcripts associated with the KEGG pathway:hsa05030:Cocaine addiction after 3 h stimulation with...
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Isolation and some properties of the thermostable beta-galactosidase of Pyrococcus woesei expressed in Escherichia coli
PublikacjaOpracowano metodę izolowania oraz zbadano właściwości enzymu otrzymanego ze szczepu Escherichia coli zawierającego gen kodujący termostabilną beta-ga-laktozydazę z Pyrococcus woesei.
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Regulated assembly of lipopolysaccharide and sensing of its alterations in Escherichia coli
PublikacjaThis thesis describes mechanism of the regulation of the transcription of the rpoE gene encoding an essential RNA polymerase subunit in Escherichia coli. The RpoE regulates extracytoplasmic stress response regulon and is required to initiate transcription of genes, whose products are involvedin the folding of periplasmic proteins and synthesis and transport of outer membrane components. The transcriptional regulation of the rpoE...
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Expression of goose parvovirus whole VP3 protein and its epitopes in Escherichia coli cells
PublikacjaThe aim of this study was the expression of goose parvovirus capsid protein (VP3) and its epitopes in Escherichia coli cells. Expression of the whole VP3 protein provided an insufficient amount of protein. In contrast, the expression of two VP3 epitopes (VP3ep4, VP3ep6) in E. coli, resulted in very high expression levels. This may suggest that smaller parts of the GPV antigenic determinants are more efficiently expressed than the...
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Phosphorylation‐mediated regulation of heat shock response in Escherichia coli
PublikacjaEscherichia coli has two heat shock regulons under the transcriptional control of Esigma(32) and Esigma(E) RNA polymerases. These polymerases control the expression of genes, the products of which are needed for correct folding of proteins in the cytoplasm and the extracytoplasm respectively. In this study, we report that mutations in a tyrosine phosphatase-encoding gene led to decreased activity of these heat shock regulons. The...
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A systematic review on cellular responses of Escherichia coli to nonthermal electromagnetic irradiation
PublikacjaInvestigation of Escherichia coli under electromagnetic fields is of significance in human studies owing to its short doubling time and human‐like DNA mechanisms. The present review aims to systematically evaluate the literature to conclude causality between 0 and 300 GHz electromagnetic fields and biological effects in E. coli. To that end, the OHAT methodology and risk of bias tool were employed. Exponentially growing cells exposed...
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Cloning of the thermostable alpha-amylase gene from Pyrococcus woesei in Escherichia coli.
PublikacjaGen kodujący alfa-amylazę z Pyrococcus woesei klonowano do plazmidów pET21d(+)lub pYTB2, którymi transformowano komórki Escherichia coli. Otrzymana rekombinantowa alfa amylaza wykazuje maksymalną aktywność przy pH 5.6 w temperaturze 95 stC i przejawia około 24 % początkowej aktywności nawet po 2 godz. inkubacji w 120 stC. Duża termostabilność otrzymanego preparatu świadczy o jego przydatności do enzymatycznego upłynniania skrobi.
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Resistance of Escherichia coli and Enterococcus spp. to selected antimicrobial agents present in municipal
PublikacjaIn this study, the susceptibility to erythromycin (E) and to trimethoprim/sulfamethoxazole (SXT) among isolates of Enterococcus spp. and Escherichia coli was tested, respectively. Both fecal indicators were detected and isolated from raw(RW) and treated wastewater (TW) as well as from samples of activated sludge (AS) collected in a local wastewater treatment plant (WWTP). Biodiversity of bacterial community in AS was also monitored...
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Identification of antigen Ag43 in uropathogenic Escherichia coli Dr+ strains and defining its role in the pathogenesis of urinary tract infections
PublikacjaUrinary tract infections (UTIs) caused by uropathogenic Escherichia coli (UPEC) are among the most common bacterial infectious diseases in the developed world. The urovirulence of UPEC is mainly associated with the surface-exposed fimbrial adhesins and adhesins of the autotransporter (AT) family. The best studied of theses proteins is antigen 43 (Ag43) mediating cell aggregation, adhesion and biofilm development as the causes of...
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Properties of recombinant trehalose synthase from Deinococcus radiodurans expressed in Escherichia coli
PublikacjaA trehalose synthase gene from Deinococcus radiodurans(DSMZ 20539)containing 1659 bp reading frame encoding 552 amino acids was amplified using PCR. The gene was finally ligated into pET30Ek/LIC vector and expressed after isopropyl β-d-thiogalactopyranoside induction in Escherichia coli (DE3) Rosetta pLysS. The recombinanttrehalose synthase (DraTreS) containing a His6-tag at the C-terminus was purified by metal affinity chromatography...
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Intra-operative biopsy in chronic sinusitis detects pathogenic Escherichia coli that carry fimG/H, fyuA and agn43 genes coding biofilm formation
PublikacjaThe aim of this study was to investigate whether or not surgical biopsy of sinus tissue in chronic sinusitis, not responsive to treatment, would detect E. coli. We intended to evaluate E. coli virulence genes, therefore dispute the causal role of such an unusual microorganism in chronic sinusitis, as well as consider effective pathogen-targeted therapy. Patients with E. coli isolated by intra-operative puncture biopsy were included...
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Escherichia coli - zapomniany patogen posocznic
PublikacjaPrzedstawiono próbę retrospektywnej analizy częstości występowania bakteriemii Gram-ujemnych, wywołanych przez E. coli u chorych hospitalizowanych w ośmiu grupach oddziałów klinicznych SPSK1 ACK AM w Gdańsku w latach 2002-2004. Dokonano oceny częstości występowania bakteriemii o etologii E. coli, liczby zgonów związanych bezpośrednio z posocznicą, analizy potencjalnych wrót zakażenia oraz analizy lekowrażliwości szczepów E. coli...
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Efficient production of Staphylococcus simulans lysostaphin in a benchtop bioreactor by recombinant Escherichia coli.
PublikacjaLysostaphin is an enzyme with bactericidal activity against Staphylococcus aureus and other staphylococcal species. In spite of many advantages and promising results of preliminary research, the enzyme is still not widely used in medicine, veterinary or as a food preservative. One of the most important factors limiting application of the enzyme in clinical or technological practice is the high costs of its production. In the present...
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Characterization of immobilized Escherichia coli cells transformed by β-galactosidase gene from Pyrococcus woesei
PublikacjaThermostable β-galactosidase from Escherichia coli transformant containing theenzyme gene from Pyrococcus woesei was immobilized on alginate gel.The benefits of using whole bacterial cells not only exclude expensive, laborious proteinisolation and purification but also stabilize enzymes by cytosol components. Increase inproductivity of enzyme can be achieved by cells permeabilization. To increase permeability ofcytoplasmic membrane...
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Tetracycline and ampicillin resistance of Escherichia coli strains of surface water origin: the potential for horizontal transfer of resistance genes = Oporność na tetracyklinę i ampicylinę szczepów Escherichia Coli wyizolowanych z wody powierzchniowej : możliwość horyzontalnego przenoszenia genów oporności
PublikacjaThe aim of this preliminary study was to assess the occurrence and molecular diversity of tetracycline and ampicillin resistance genes carried by Escherichia coli present in surface water. Bacterial strains were isolated from two watercourses (the Reda River and the Oliwski Stream) that influence the quality of coastal waters in the Gdańsk Bay (Northern Poland) by direct discharge. The bacterial drug susceptibility, tested against...
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Molecular aspects of biogenesis of Escherichia coli Dr Fimbriae: characterization of DraB-DraE complexes
PublikacjaHemaglutynina Dr uropatogennych szczepów Escherichia coli jest fimbrialnym homopolimerem zbudowanym z podjednostek białkowych DraE kodowanych przez operon dra. Operon dra zawiera geny draB i draC, kodujące białka homologiczne do białek (białko opiekuńcze-białko kanałotwórcze) zaangażowanych w procesie biogenezy struktur polimerycznych eksprymowanych powierzchniowo. Białko DraB jest jednym z białek periplazmatycznych, należącym...
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Expression of Deinococcus geothermalis Trehalose Synthase Gene in Escherichia coli and Its Enzymatic Properties
PublikacjaA novel trehalose synthase gene from Deinococcus geothermalis (DSMZ 11300) containing 1,692 bp reading-frame encoding 564 amino acids was amplified using PCR. The gene was ligated into pET30Ek/LIC vector and expressed after isopropyl alfa-D-thiogalactopyranoside induction in Escherichia coli BL21(DE3)pLysS. The recombinant trehalose synthase (DgeoTreS) containing a His6 tag at the C-terminus was purified by metal affinity chromatography...
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Molecular and structural basis of inner core lipopolysaccharide alterations in Escherichia coli: incorporation of glucuronic acid and phosphoethanolamine in the heptose region.
PublikacjaIt is well established that lipopolysaccharide (LPS) often carries nonstoichiometric substitutions in lipid A and in the inner core. In this work, the molecular basis of inner core alterations and their physiological significance are addressed. A new inner core modification of LPS is described, which arises due to the addition of glucuronic acid on the third heptose with a concomitant loss of phosphate on the second heptose. This...
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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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Comparative analysis of mRNA transcripts of HT-29 cell line expressed in identical quantities for pathogenic E. coli strains UM146 and UM147 with control Escherichia coli Nissle 1917
PublikacjaAim of study was comparative analysis of mRNA transcripts of HT-29 cell line, expressed in identical quantities for the combination of pathogenic and non-pathogenic Escherichia coli strains. HT-29 confluent monolayers infection with two pathogenic E. coli strains UM146 and UM147 resulted in two sets of mRNA transcripts that were identical with RNA transcripts obtained for non-pathogenic one strain E. coli Nissle 1917. In this study...
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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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Hydrolytic and transgalactosylation activities of immobilized Escherichia coli cells transformed by β-galactosidase gene from Pyrococcus woesei
PublikacjaPrzedstawiono wyniki badań dotyczących skuteczności transformacji laktozy katalizowanej immobilizowanymi w żelu alginianowym rekombinantowymi komórkami Escherichia coli, transformowanymi genem b-galaktozydazy z Pyrococcus woesei. Wykazano, że aktywność hydrolityczna rekombinantowych komórek wzrasta o 35% po permeabilizacji w środowisku 40% etanolu. Optymalna temperatura i pH katalizowanej reakcji wynosiły odpowiednio 98C i 5,4....
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Wykorzystanie komórek Escherichia coli transformowanych genem termostabilnej beta-galaktozydazy z Pyrococcus woesei do wytwarzania galaktozylofruktozy
PublikacjaKomórki rekombinantowej Escherichia coli transformowane genem beta-galaktozydazy z Pyrococcus woesei wykorzystano jako biokatalizator syntezy galaktozylofruktozy. Największą aktywność syntezy wymienionego prebiotyku (7,6 g/L x godz)uzyskano w 80C przy pH 5,4, stosując jako substrat roztwór zawierający 10% laktozy i 20% fruktozy. Aktywność transgalaktozylacji nie ulegała istotnym zmianom podczas sześciu kolejnych szarż produkcyjnych.
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Identification of Substrates of Cytoplasmic Peptidyl-Prolyl Cis/Trans Isomerases and Their Collective Essentiality in Escherichia Coli
PublikacjaProtein folding often requires molecular chaperones and folding catalysts, such as peptidyl-prolyl cis/trans isomerases (PPIs). The Escherichia coli cytoplasm contains six well-known PPIs, although a requirement of their PPIase activity, the identity of their substrates and relative enzymatic contribution is unknown. Thus, strains lacking all periplasmic and one of the cytoplasmic PPIs were constructed. Measurement of their PPIase...
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Role of the disulfide bond in stabilizing and folding of the fimbrial protein DraE from uropathogenic Escherichia coli
PublikacjaDr fimbriae are homopolymeric adhesive organelles of uropathogenic Escherichia coli composed of DraE subunits, responsible for the attachment to host cells. These structures are characterized by enormously high stability resulting from the structural properties of an Ig-like fold of DraE. One feature of DraE and other fimbrial subunits that makes them peculiar among Ig-like domain-containing proteins is a conserved disulfide bond...