Renata Godlewska

University of Warsaw | UW · Institute of Microbiology

Helicobacter pylori ( H. pylori ) is a Gram-negative bacterium that colonizes the human stomach leading to the development of chronic gastritis, peptic ulcers and gastric adenocarcinoma. A combination of host, environment and bacterial virulence factors contribute to disease development. The H. pylori TNFα inducing protein (Tipɑ) is a virulence fac...

Pathogenic bacteria interact with cells of their host via many factors. The surface components , i.e., adhesins, lipoproteins, LPS and glycoconjugates, are particularly important in the initial stages of colonization. They enable adhesion and multiplication, as well as the formation of biofilms. In contrast, virulence factors such as invasins and t...

Since 2005, campylobacteriosis has been the most common zoonotic disease in Europe. The main reservoir of pathogenic Campylobacter strains is broilers, which makes raw and undercooked poultry meat two major sources of disease. Infection in chicken flocks is most often asymptomatic, despite a high level of colonization reaching 106–109cfu/g in anima...

The proteomes of outer membrane vesicles (OMVs) secreted by C. jejuni 81–176 strain, which was exposed to oxygen or antibiotic stress (polymyxin B), were characterized. We also assessed the OMVs production and their content in two mutated strains – ∆dsbI and ∆htrA. OMVs production was significantly increased under the polymyxin B stress and remaine...

The study aimed to investigate the effectiveness of photodynamic therapy in the elimination of intracanal Enterococcus faecalis biofilm and to analyse how a repeated light irradiation, replenishment of oxygen and photosensitiser affect the results of the photodynamic disinfecting protocol. After chemomechanical preparation, 46 single-rooted human t...

Outer membrane vesicles (OMVs) are extracellular structures produced by most gram-negative bacteria, including pathogens of humans and animals. OMVs play an important role in the physiology of microorganisms and are an integral part of many biological processes. Following the discovery that they are able to transport many biomolecules, also these w...

Background. Photodynamic therapy is a new treatment protocol used in many areas of medicine. It has the potential to eliminate bacteria, fungi and parasites that may cause different pathological states. Objectives. The aim of the study was to evaluate the efficacy of a specific photodynamic protocol in the reduction of Enterococcus faecalis biofilm...

Campylobacter jejuni is the most prevalent cause of a food-borne gastroenteritis in the developed world, with poultry being the main source of infection. Campylobacter jejuni, like other Gram-negative bacteria, constitutively releases outer membrane vesicles (OMVs). OMVs are highly immunogenic, can be taken up by mammalian cells, and are easily mod...

Enterococci are Gram-positive, catalase-negative, facultative anaerobic bacteria. They inhabit the oral cavity and gastrointestinal tract in humans as normal commensals. However, they can also cause infections of the urinary tract, surgical wound infections, neonatal sepsis and endocarditis. Enterococcus faecalis is associated with great number of...

Campylobacter spp, especially the species Campylobacter jejuni, are important human enteropathogens responsible for millions of cases of gastro-intestinal disease worldwide every year. C. jejuni is a zoonotic pathogen, and poultry meat that has been contaminated by microorganisms is recognized as a key source of human infections. Although numerous...

Western blot analysis of the specificity of 6xHis-rCjaAD-LysM. Proteins were separated by 12% SDS-PAGE under reducing conditions and probed with: (A) anti-LysM, (B) anti-CjaA, and (C) anti-CjaD antibodies. Lanes: 1 – purified protein 6xHis-rCjaAD-LysM, M – protein molecular-weight marker.

Western blot analysis of the specificity of anti-LysM serum. Protein extracts purified by affinity chromatography were separated by 12% SDS-PAGE under reducing conditions and probed with anti-LysM antibodies. Lanes: 1 – 6xHis-LysM, 2 – 6xHis-CjaA-LysM; 3 – 6xHis-CjaD-LysM; M – protein molecular-weight marker.

Localization of rCjaADLysM fusion protein on TCA-pretreated L. salivarius. Fusion protein were visualized with anti-rCjaAD antibodies that were further detected with goat anti-rabbit IgG Alexa Fluor A488. Fluorescence was visualized with a NIKON A1R MP microscope. The bar represents 2 μm.

Helicobacter pylori does not encode the classical DsbA/DsbB oxidoreductases that are crucial for oxidative folding of extracytoplasmic proteins. Instead, this microorganism encodes an untypical two proteins playing a role in disulfide bond formation – periplasmic HP0231, which structure resembles that of EcDsbC/DsbG, and its redox partner, a membra...

Bacterial Dsb enzymes are involved in the oxidative folding of many proteins, through the formation of disulfide bonds between their cysteine residues. The Dsb protein network has been well characterized in cells of the model microorganism Escherichia coli. To gain insight into the functioning of the Dsb system in epsilon-Proteobacteria, where it p...

Campylobacter jejuni is a major food-borne pathogen, causing gastroenteritis worldwide. Chickens are considered to be one of the most common sources of human C. jejuni infection in developed countries. Campylobacter CjaD/Pal protein (annotated as Cj0113 in C. jejuni strain NCTC11168) is a highly immunogenic, membrane-located antigen, conserved amon...

ABSTRACT: After publication of this work [Grabowska et al. BMC Microbiol 2011, 11:166.], it came to our attention that the grant numbers in the Acknowledgements section were incorrect. This work was supported by two grants from Polish Ministry of Science and Higher Education (No. N303 341835 and N401 183 31/3968) and by intramural grant of Universi...

Experiment details concerning DsbI stability and glycosylation.

Influence of the dba/Dba on DsbI stability in E. coli cells. Western blot (anti-rDsbI) analysis of C. jejuni/E. coli protein extracts separated by 12% SDS-PAGE. Relative positions of molecular weight markers (lane 1) are listed on the left (in kilodaltons). Lanes 2-7 contain 20 μg of total proteins from: C. jejuni 81-176 wt (2), E. coli/pBluescript...

DsbI glycosylation. Western blot (anti-rDsbI) analysis of C. jejuni protein extracts separated by 12% SDS-PAGE. A - proteins isolated from C. jejuni 81-176 wt and pglB isogenic mutant. Relative positions of molecular weight markers (lane 1) are listed on the left (in kilodaltons). Lanes 2 and 3 contain 20 μg of total proteins from: C. jejuni 81-176...

Arylsulfatase (AstA) assay in C. jejuni 81-176 cells. Arylsulfatase (AstA) activity of C. jejuni 81-176 cultivated on MH liquid medium under high- and low-iron conditions (chelator) till the culture reached OD600 ~0,6-0,7. Results are from four assays with each sample performed in triplicate. Values are reported as arylsulphatase units. One unit eq...

Many bacterial extracytoplasmic proteins are stabilized by intramolecular disulfide bridges that are formed post-translationally between their cysteine residues. This protein modification plays an important role in bacterial pathogenesis, and is facilitated by the Dsb (disulfide bond) family of the redox proteins. These proteins function in two par...

The protein Pal (peptidoglycan-associated lipoprotein) is anchored in the outer membrane (OM) of Gram-negative bacteria and interacts with Tol proteins. Tol-Pal proteins form two complexes: the first is composed of three inner membrane Tol proteins (TolA, TolQ and TolR); the second consists of the TolB and Pal proteins linked to the cell's OM. Thes...

The Campylobacter coli 72Dz/92 cjaA gene (orthologue of cj0982c of C. jejuni NCTC 11168) product is a highly immunogenic, amino acid-binding protein. CjaA was palmitic acid-modified when processed in E. coli. In addition, site-directed mutagenesis of the Cys residue of the LAAC motif of its signal sequence confirmed that CjaA is a lipoprotein when...

A product of the Helicobacter pylori hp0596 gene (Tip-α) is a highly immunogenic homodimeric protein, unique for this bacterium. Cell fractionation experiments indicate that Tip-α is anchored to the inner membrane. In contrast, the three-dimensional model of the protein suggests that Tip-α is soluble or, at least, largely exposed to the solvent. hp...

Despite the enormous progress in understanding the process of bacterial pathogenesis and interactions of pathogens with eucaryotic cells the infectious diseases still remain the main cause of human premature deaths. It is now recognized that Helicobacter pylori infects about half of the world's population. Based on results of clinical studies the W...

Helicobacter pylori, Gram-negative spiral-shaped bacterium and a member of the ε-Proteobacteria, colonizes the gastric mucosa of humans. It was first isolated in 1983 from a patient with chronic active gastritis. It is now recognized that H. pylori infects about half of the world's population (87% of the Polish population). H. pylori has been ident...

Dsb proteins control the formation and rearrangement of disulfide bonds during the folding of membrane and exported proteins. Here we examined the role of DsbI protein in Helicobacter pylori pathogenesis and demonstrated that a dsbI mutant impaired in disulfide bond formation revealed a greatly reduced ability to colonize mice gastric mucosa.

Lipid modified proteins, which belong to a group of membrane proteins, are present in cells of various organisms, from bacteria to eukaryotes. Lipid modification of these proteins occurs post-translationally on the periplasmic surface of the inner membrane. Lipoproteins of Gram-negative bacteria are anchored into inner or outer membrane via fatty a...

Several pathogenic bacteria are able to trigger apoptosis in the host cell, but the mechanisms by which it occurs differ, and the resulting pathology can take different courses. Induction and/or blockage of programmed cell death upon infection is a result of complex interaction of bacterial proteins with cellular proteins involved in signal transdu...

In Gram-negative bacterial cells, disulfide bond formation occurs in the oxidative environment of the periplasm and is catalysed by Dsb (disulfide bond) proteins found in the periplasm and in the inner membrane. In this report the identification of a new subfamily of disulfide oxidoreductases encoded by a gene denoted dsbI, and functional character...

Helicobacter pylori, one of the most common bacterial pathogens of humans, is a curved, microaerophilic, Gram-negative bacterium that persistently colonizes the gastric epithelium, causes gastritis, peptic ulcer disase, and is associated with certain types of gastric cancer. The analysis of the complete genomic sequence of two unrelated pathogenic...

Screening of the Helicobacter pylori genomic library with sera from infected humans and from immunized rabbits resulted in identification of the 25 kDa protein cell envelope (HppA) which exhibits acid phosphatase activity. Enzyme activity was demonstrated by specific enzymatic assays with whole-cell protein preparations of H. pylori strain N6 and f...

The powerful combination of the gene cloning methods with the rapid progress in the sequencing techniques followed by the combination of genomics and bioinformatics provided fresh insight into physiology and pathogenicity of many important agent of human diseases. Analysis of the complete genome sequence allows to classified annotated ORF, potentia...

Prevention of Helicobacter pylori infection may help to control related gastritis, peptic ulcer and cancer. Of the possible preventive measures, immunization was successfully employed in various animal studies. However, no immunization protocol has been accepted for humans. A better characterization of the immune response against the pathogen may b...