Agnieszka Wyszyńska

University of Warsaw | UW · Department of Bacterial Genetics

Campylobacter jejuni/coli infections are the leading cause of bacterial diarrheal illnesses in humans. Many epidemiological studies indicate that improperly prepared meat from chickens that carry a high load of Campylobacter in their intestinal tracts is the key source of human infections. LAB, mainly members of the Lactococcus and Lactobacillus ge...

Among Psychrobacter spp., there are several multireplicon strains, carrying more than two plasmids. Psychrobacter sp. ANT_H3 carries as many as 11 extrachromosomal replicons, which is the highest number in Psychrobacter spp. Plasmids of this strain were subjected to detailed genomic analysis, which enables an insight into the structure and function...

Streszczenie Postępy w genomice związane z ustawicznym sekwencjonowaniem kompletnych genomów drobnoustrojów, w tym mikroorganizmów patogennych, zrewolucjonizowały podejście do wyboru i projektowania antygenów szczepionkowych nowej generacji. Odwrócono klasyczny proces badawczy, ponieważ to zbiór danych genomowych stał się źródłem hipotez o immunoge...

The repABC replication/partitioning loci are widespread in extrachromosomal replicons of Alphaproteobacteria . They are evolutionarily diverse, subject to multi-layer self-regulation, and are responsible for the maintenance of different types of replicons, such as plasmids (e.g., Agrobacterium pTi and pRi tumorigenic and rhizogenic plasmids), megap...

The bacterial proteins of the Dsb family catalyze the formation of disulfide bridges between cysteine residues that stabilize protein structures and ensure their proper functioning. Here, we report the detailed analysis of the Dsb pathway of Campylobacter jejuni. The oxidizing Dsb system of this pathogen is unique because it consists of two monomer...

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...

Campylobacter jejuni / coli is the leading bacterial cause of diarrhoea in humans in both developing and developed countries. Epidemiological studies show that most cases of campylobacteriosis are the result of the consumption of undercooked, contaminated poultry meat. Although campylobacteriosis is largely a self-limiting disease with low mortalit...

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...

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...

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.

Campylobacter jejuni is the most frequent cause of human food-borne gastroenteritis and chicken meat is the main source of infection. Recent studies showed that broiler chicken immunization against Campylobacter should be the most efficient way to lower the number of human infections by this pathogen. Induction of the mucosal immune system after or...

Erratum to: Appl Microbiol Biotechnol (2015) 99:2967-2977DOI 10.1007/s00253-015-6498-0In the original publication, wrong number of supporting grant has been given in the Acknowledgments Section. The correct version is given below:The work was supported by grants from the National Science Center, Poland (grants No 2011/03/B/NZ1/00592) and by Europea...

Lactic acid bacteria are a group of Gram-positive bacteria that include many species, such as Lactococcus, Lactobacillus, Leuconostoc and others. They have health benefits such as immunomodulation and production of antimicrobial substances active against gastric and intestinal pathogens and other microbes. Over the past decade, there has been incre...

Lactic acid bacteria (LAB) are a diverse group of Gram-positive, nonsporulating, low G + C content bacteria. Many of them have been given generally regarded as safe status. Over the past two decades, intensive genetic and molecular research carried out on LAB, mainly Lactococcus lactis and some species of the Lactobacillus genus, has revealed new,...

Food poisoning and diarrheal diseases continue to pose serious health care and socioeconomic problems worldwide. Campylobacter spp. is a very widespread cause of gastroenteritis. Over the past decade there has been increasing interest in the use of lactic acid bacteria (LAB) as mucosal delivery vehicles. They represent an attractive opportunity for...

Fig. S2 CjaA localization in S. Typhimurium strain χ9718 (pYA4346, pUWM1161). Bacteria were grown in nutrient broth containing 0.2 % mannose. S. Typhimurium cells were subjected to a fractionation procedure to obtain cytoplasmic (C), periplasmic (P), inner (IM) and outer membrane (OM) fractions. The proteins were derived from equal amounts of cells...

Campylobacter spp. are regarded as the most common bacterial cause of gastroenteritis worldwide, and consumption of chicken meat contaminated by Campylobacter is considered to be one of the most frequent sources of human infection in developed countries. Here we evaluated the immunogenicity and protective efficacy of Salmonella Typhimurium χ9718 pr...

The cytolethal distending toxins (CDTs) comprise a family of intracellulary acting bacterial protein genotoxins, produced by a variety of Gram-negative pathogenic bacteria, which cause DNA damage in the target cells. The DNA damage-response in the initiated cell results in the characteristic and irreversible cell cycle arrest and apoptosis in a bro...

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...

Numerous organisms produce antimicrobial peptides (AMP) as part of their innate immunity and host defense. Antimicrobial peptides are implicated in antibacterial as well as antifungal activity in phagocytes, inflammatory fluids and intestinal secretions. Among them, the most abundant and the best characterized are defensins. Most of them have been...

The Dsb family of redox proteins catalyzes disulfide bond formation and isomerization. Since mutations indsb genes change the conformation and stability of many extracytoplasmic proteins, and since many virulence factors of pathogenic bacteria are extracytoplasmic, inactivation ofdsb genes often results in pathogen attenuation. This study investiga...

Campylobacteriosis constitutes a serious medical and socioeconomic problem worldwide. Rapidly increasing antibiotic resistance of bacterial strains compels us to develop alternative therapeutic strategies and to search for efficient immunoprophylactic methods. The vast majority of Campylobacter infections in developed countries occur as sporadic ca...

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...

Infectious diseases still remain the main cause of human premature deaths; especially in developing countries. The emergence and spread of pathogenic bacteria resistant to many antibiotics (multidrug-resistant strains) have created the need for the development of novel therapeutic agents. Only two new classes of antibiotics of novel mechanisms of a...

Campylobacter is an asaccharolytic microorganism which uses amino acids as a source of carbon and energy. CjaC/HisJ is a ligand-binding protein, a component of the ABC transport system. Campylobacter CjaC/HisJ is post-translationally modified by glycosylation. The number of glycosylation motifs present in the CjaC protein is species-specific. C. co...

Campylobacter spp, gramnegative microorganisms, are currently recognized as a major cause of human acute bacterial enteritis. This bacterium frequently promotes a commensal lifestyle in the gastrointestinal tracts of many animals including birds. The main route of human infections is through improperly handled or undercooked poultry meat. This revi...

We investigated the regulation of the cjaA and cjaB genes of Campylobacter coli. These genes are seemingly arranged into one operon but appear to encode functionally different proteins i.e. an extracytoplasmic solute receptor and a MHS - metabolite: H+ symporter transport protein. Analysis of various transcriptional cjaA and/or cjaB lacZ fusion con...

During the past 100 years, the widespread use of vaccines has begun to ameliorate the devastating effects of infectious disease, increasing the average life expectancy and enhancing the quality of life of those who have been vaccinated. Smallpox has been eradicated and other diseases such as poliomyelitis or measles have been reduced to very low le...

Campylobacter jejuni is a leading cause of acute bacterial gastroenteritidis in humans. However the bacterium is commensal in cattle, swine and birds. Colonization of the chick gastrointestinal track is multifactorial process. Numerous studies such as STM mutagenesis, differential hybridization and comparative genomics resulted in identification of...

Glycosylation is considered to be the most frequent system of protein modification in eukaryotic cells. It has been recently established that also many bacterial proteins are modified by glycosylation and now it is widely accepted that prokaryotes (Archaea and Bacteria) express glycoproteins. In Gram-negative bacteria O-linked as well as N-linked g...

It is well documented that poultry and poultry products are the major source of human campylobacteriosis and salmonellosis. This study examined the general efficacy of avirulent Salmonella vaccine strains expressing Campylobacter antigen as a bivalent chicken vaccine prototype. Three C. jejuni genes: cjaA (cj0982c), cjaC (cj0734c) and cjaD (cj0113)...

Although vaccination, after having been more than 200 years in medical practice, has proven to be the most effective and the cheapest way to prevent infectious diseases, they remain still the main cause of human premature deaths. As many pathogens enter the human body through the mucosal surfaces, the mucosal way of immunization is considered to be...

Immunogenic C. coli CjaA protein is a candidate for a chicken anti-Campylobacter subunit vaccine. In order to enhance its immunogenicity an antigenic determinant of the CjaA protein was identified. Thereafter, two copies of the antigenic epitope were cloned in tandem directly or with a flexible hinge between them. All experiments documented that th...

Campylobacter jejuni 72Dz/92 cjaD gene, orthologue of C. jejuni NCTC 11168 cj0113, C. jejuni M275 omp18 and C. jejuni ATCC 29428 omp18, has been cloned, sequenced and analysed from the viewpoint of its immunological attributes. Neither the 5' nor 3' fragment of the cjaD encodes protein capable of reacting with anti-Campylobacter antibodies. Several...

Three Campylobacter jejuni 72Dz/92 genes (cjaA (ompH1), cjaC (hisJ) and cjaD (omp18)) encoding immunodominant proteins are considered to be potential chicken vaccine candidates. The presence and conservation of cjaA, cjaC and cjaD genes among different Campylobacter clinical isolates were determined. The genes were detected in thirty Campylobacter...

Three Campylobacter jejuni 72Dz/92 genes (cjaA (ompH1), cjaC (hisJ) and cjaD (omp18)) encoding immunodominant proteins are considered to be potential chicken vaccine candidates. The presence and conservation of cjaA, cjaC and cjaD genes among different Campylobacter clinical isolates were determined. The genes were detected in thirty Campylobacter...