Sylwia Kamila Bloch

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Shiga toxin-producing Escherichia coli (STEC) strains belong to the group of pathogens that cause bloody diarrhea and hemorrhagic colitis with often severe complications. The main problem with human pathogenic E. coli strains, including STEC, is a wide spectrum of phenotypes and clinical manifestations. It is related to a variety of exchangeable genetic(More)
The marine environment is estimated to be one of the most significant sources of biological activity in the world. In the last few decades an increase in the research intensity conducted on marine microorganisms has been observed, which confirms the great potential of these organisms in the field of bioactive compounds' production. In order to efficiently(More)
The exo–xis region, present in genomes of lambdoid bacteriophages, contains highly conserved genes of largely unknown functions. In this report, using bacteriophage λ and Shiga toxin-converting bacteriophage ϕ24Β, we demonstrate that the presence of this region on a multicopy plasmid results in impaired lysogenization of Escherichia coli and delayed, while(More)
A microRNA-size (20-nt long) molecule has been identified in Escherichia coli after induction of Shiga toxin-converting bacteriophage Φ24B. This small RNA, named 24B_1, is encoded in the lom-vb_24B_43 region of the phage genome, and apparently it is produced by cleavage of a larger transcript. A phage devoid of 24B_1 revealed decreased efficiency of(More)
Lambdoid bacteriophages serve as useful models in microbiological and molecular studies on basic biological process. Moreover, this family of viruses plays an important role in pathogenesis of enterohemorrhagic Escherichia coli (EHEC) strains, as they are carriers of genes coding for Shiga toxins. Efficient expression of these genes requires lambdoid(More)
BACKGROUND It is generally believed that there are many natural sources of as yet unknown bioactive compounds with a high biotechnological potential. However, the common method based on the use of cell extracts in the preliminary screening for particular molecules or activities is problematic as amounts of obtained compounds may be low, and such experiments(More)
Metagenomics is a powerful tool to better understand the microbial niches, especially these from extreme habitats like oceans and seas, hot springs or deserts. However, one who is going to face the metagenomic studies should realize the challenges which might occur in the course of experiments. This manuscript indicates common problems in function-driven(More)
Virulence of enterohemorrhagic Escherichia coli (EHEC) strains depends on production of Shiga toxins. These toxins are encoded in genomes of lambdoid bacteriophages (Shiga toxin-converting phages), present in EHEC cells as prophages. The genes coding for Shiga toxins are silent in lysogenic bacteria, and prophage induction is necessary for their efficient(More)
A large scale analysis presented in this article focuses on biological and physiological variety of bacteriophages. A collection of 83 bacteriophages, isolated from urban sewage and able to propagate in cells of different bacterial hosts, has been obtained (60 infecting Escherichia coli, 10 infecting Pseudomonas aeruginosa, 4 infecting Salmonella enterica,(More)
A novel procedure for the detection of specific DNA sequences has been developed. This procedure is based on the already known method employing PCR with appropriate primers and a sequence-specific DNA probe labeled with the fluorescent agent 6-carboxylfluorescein (FAM) at the 5' end and the fluorescence quencher BHQ-1 (black hole quencher) at the 3' end.(More)