Wyniki wyszukiwania - Biblioteka Nauki

1

Chlamydial plasmids and bacteriophages

100%

Pawlikowska-Warych M. , Śliwa-Dominiak J. , Deptuła W.

Acta Biochimica Polonica

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2015

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tom 62

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nr 1

1-6

EN

Chlamydia are absolute pathogens of humans and animals; despite being rather well recognised, they are still open for discovery. One such discovery is the occurrence of extrachromosomal carriers of genetic information. In prokaryotes, such carriers include plasmids and bacteriophages, which are present only among some Chlamydia species. Plasmids were found exclusively in Chlamydia (C.) trachomatis, C. psittaci, C. pneumoniae, C. suis, C. felis, C. muridarum and C. caviae. In prokaryotic organisms, plasmids usually code for genes that facilitate survival of the bacteria in the environment (although they are not essential). In chlamydia, their role has not been definitely recognised, apart from the fact that they participate in the synthesis of glycogen and encode proteins responsible for their virulence. Furthermore, in C. suis it was evidenced that the plasmid is integrated in a genomic island and contains the tetracycline-resistance gene. Bacteriophages specific for chlamydia (chlamydiaphages) were detected only in six species: C. psittaci, C. abortus, C. felis, C. caviae C. pecorum and C. pneumoniae. These chlamydiaphages cause inhibition of the developmental cycle, and delay transformation of reticulate bodies (RBs) into elementary bodies (EBs), thus reducing the possibility of infecting other cells in time. Plasmids and bacteriophages can be used in the diagnostics of chlamydioses; although especially in the case of plasmids, they are already used for detection of chlamydial infections. In addition, bacteriophages could be used as therapeutic agents to replace antibiotics, potentially addressing the problem of increasing antibiotic-resistance among chlamydia.

2

Quick and efficient method for recovering of bacteriophages from soft agar after their propagation by the plate lysate technique

100%

Obuchowski M. , Stopa M.

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1993

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tom 40

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nr 1

3

Somatic and F-specific bacteriophages in waters of the small, municipal Rusałka Lake in Szczecin

88%

Pawlikowska-Warych M. , Czuprynska P. , Tokarz-Deptula B. , Deptula W.

Acta Biologica

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2019

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tom 26

4

The comparative characteristics of DNAs isolated from transducing bacteriophages of Staphylococcus aureus

88%

Mlynarczyk G. , Mlynarczyk A. , Jagusztyn-Krynicka E. , Zawidzka E. , Sawicka-Grzelak A. , Osowiecki H.

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nr 10-12

5

Role of cholera toxin in Vibrio cholerae infection in humans - a review

88%

Pal P.

International Letters of Natural Sciences

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2014

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tom 17

EN

Vibrio cholerae, the causative agent of Asiatic cholera, is a gram-negative motile bacterial species acquired via oral ingestion of contaminated food or water sources. Cholera has spread from the Indian subcontinent where it is endemic to involve nearly the whole world seven times during the past 185 years. V. cholerae serogroup O1, biotype El Tor, has moved from Asia to cause pandemic disease in Africa and South America during the past 35 years. A new serogroup, O139, appeared in south Asia in 1992, has become endemic there, and threatens to start the next pandemic. The facultative human pathogen V. cholerae represents a paradigm that evolved from environmental non-pathogenic strains by acquisition of virulence genes. The major virulence factors of V. cholerae, cholera toxin (CTX) encoded by the ctxAB genes residing in the genome of filamentous lysogenic bacteriophage (CTXɸ) and toxin coregulated pilus (TCP) encoded by vibrio pathogenicity island (VPI). CTX, a potent stimulator of adenylate cyclase, causes the intestine to secrete watery fluid rich in sodium, bicarbonate, and potassium, in volumes far exceeding the intestinal absorptive capacity, by ADP-ribosylation of the alpha subunit of the GTP-binding protein. Thus intestinal infection with V. cholerae results in the loss of large volumes of watery stool, leading to severe and rapidly progressing dehydration and shock. Without adequate and appropriate rehydration therapy, severe cholera kills about half of affected individuals. Today, cholera still remains a burden mainly for underdeveloped countries, which cannot afford to establish or to maintain necessary hygienic and medical facilities. During the last three decades, intensive research has been undertaken to unravel the virulence properties and to study the epidemiology of this significant human pathogen. This review provides an overview of the role of CTX in the occurrence of this disease in humans.

6

Bacteriophage contamination: is there a simple method to reduce its deleterious effects in laboratory cultures and biotechnological factories?

88%

Los M. , Czyz A. , Sell E. , Wegrzyn A. , Neubauer P. , Wegrzyn G.

Journal of Applied Genetics

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2004

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tom 45

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nr 1

7

Preparation of endotoxin-free bacteriophages

88%

Boratynski J. , Syper D. , Weber-Dabrowska B. , Lusiak-Szelachowska M. , Pozniak G. , Gorski A.

Cellular and Molecular Biology Letters

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2004

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tom 09

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nr 2

EN

Bacteriophages (phages) are bacterial viruses that interact with bacterial walls and invade bacterial cells. Moreover, they disturb bacterial metabolism and lead to bacteria lysis. In the case of Gram-negative bacteria crude phage cultures, apart from the phages themselves, the bacterial debris, bacterial proteins and nucleic acids contain endotoxins. These endotoxins (lipopolysaccharides) posses a high degree of toxicity in vitro and in vivo, and their removal is essential for safety in antibacterial bacteriophage therapy. An effective, scaleable purification of bacteriophages from endotoxins was accomplished by sequential ultrafiltration through polysulfone membrane (30 nm) followed by chromatography on sepharose 4B and Matrex Cellulofine Sulfate. The phage fraction after gel filtration chromatography routinely contained endotoxins in the 150-2500 EU/mL range. The procedure yielded bacteriophages contaminated with as little as 0.4-7 EU/ml (Limulus assay). This value lies within the permitted level for intravenous applications (5 EU/kg/h by European Pharmacopoeia, 1997)

8

The influence of environmental factors on survival of Yersinia enterocolitica 0:3

88%

Kot B. , Blaszczyk M. , Kulawiec U.

Polish Journal of Environmental Studies

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2005

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tom 14

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nr 3

EN

The influence of the presence of bacteriophage ZD5, temperature, pH and the interaction of these factors on survival of Y. enterocolitica cells in pond water and buffers was examined. The presence of bacteriophage ZD5 and temperature have substantial influence on survival of Y. enterocolitica cells in buffers with different pHs. The statistical analysis showed a significant influence of the presence of phage ZD5 on the decrease in the number of Y. enterocolitica cells incubated in buffers with pHs 6, 7, and 8. In the presence of phage ZD5, pH itself turned out to be of no significance because the average numbers of Y. enterocolitica cells obtained in pHs 6, 7, and 8 did not differ significantly at p≤0.05. Statistical analysis confirms significant influence of the presence of phage ZD5 on the reduction of the number of Y. enterocolitica cells in pond water at both 4°C and 20°C. The lowest average value of the number of cells was obtained at 4°C in the presence of phage ZD5, both in the tested buffers and in the pond water.

9

Call for a dedicated European legal framework for bacteriophage therapy

75%

Verbeken G. , Pirnay J.-P. , Lavigne R. , Jennes S. , De Vos D. , Casteels M. , Huys I.

Archivum Immunologiae et Therapiae Experimentalis

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2014

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tom 62

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nr 2

10

Construction and characterization of hybrids containing genes coding for proteins of the central part of bacteriophage T4 baseplate

75%

Nieradko J. , Szewczyk B.

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1990

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tom 39

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nr 1-2

11

Zastosowanie bakteriofagów i enzymów fagowych w produkcji żywności

75%

Drulis-Kawa Z. , Maciejewska B. , Olszak T.

Laboratorium - Przegląd Ogólnopolski

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2014

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tom nr 11-12

46--50

PL

Problem zabezpieczenia żywności przed patogennymi bakteriami, takimi jak Escherichia coli O157, Listeria monocytogenes, Staphylococcus aureus czy Salmonella enterica, od lat spędza sen z powiek producentom żywności, mikrobiologom i lekarzom. Wiele grup badawczych poszukuje rozwiązania tego problemu w zastosowaniu bakteriofagów litycznych oraz kodowanych przez nie enzymów o właściwościach przeciwbakteryjnych. Potencjalne możliwości zastosowania wirusów bakteryjnych oraz ich białek przedstawiono w niniejszym artykule.

EN

The issue of the food protection against foodborne pathogens such as Escherichia coli O157, Listeria monocytogenes, Staphylococcus aureus and Salmonella enterica vexes food producers, microbiologists and clinicians for many years. The solution of this problem can be found in the utilization of lytic phages and their antibacterial enzymes. Potential applications of bacterial viruses, and their proteins are presented in this article.

12

CRISPR/Cas9 immune system as a tool for genome engineering

75%

Hryhorowicz M. , Lipinski D. , Zeyland J. , Slomski R.

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nr 3

13

The activity of chosen bacteriophages on Yersinia enterocolitica strains

75%

Kot B. , Bukowski K. , Jakubczak A. , Kaczorek I.

Polish Journal of Veterinary Sciences

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2002

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tom 05

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nr 1

14

The optimal eukaryotic signal for translation initiation from non-aug codons, present upstream of bacteriophage lambda P cistron, is inactive in Escherichia coli

75%

Wrobel B. , Slominski B. , Wegrzyn G.

Cellular and Molecular Biology Letters

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2003

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tom 08

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nr 2

EN

Expression of the replication genes of bacteriophage λ, O and P, is believed to be translationally coupled. However, it was previously noted that, under conditions of amino acid starvation, when O is not synthesized, P continues to be expressed at a relatively high level. The results presented in this report, contrary to the previously presented hypothesis, suggest that an AGACUGGAU sequence (an optimal context for translation initiation from non-AUG codons in eukaryotes, and present upstream the P cistron) is inactive in Escherichia coli. Comparative sequence analysis confirms that such a signal is unlikely to be important for P synthesis. Instead, a weak Shine-Dalgarno sequence may be present upstream the P cistron, and be active in the absence of O gene expression.

15

Bacteriophages provide regulatory signals in mitogen-induced murine splenocyte proliferation

75%

Zimecki M. , Weber-Dabrowska B. , Lusiak-Szelachowska M. , Mulczyk M. , Boratynski J. , Pozniak G. , Syper D. , Gorski A.

Cellular and Molecular Biology Letters

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2003

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tom 08

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nr 3

EN

The aim of this investigation was to reveal the regulatory properties of bacteriophage preparations in a model of mitogen-induced splenocyte proliferation in mice. We showed that sepharose 4B-purified preparations of the Staphylococcus aureus phage A20/R exhibited costimulatory activity in splenocyte proliferation induced by suboptimal (0.25 μg/ml) concentrations of ConA. On the other hand, the purified phage fraction was regulatory with regard to splenocyte proliferation induced by the optimal (2.5 μg/ml) ConA concentration. We also showed that the phage preparation can elicit IL-6 production in splenocyte cultures and enhance ConA-induced production of that cytokine. Furthermore, the phages preferentially induced IL-6 production in adherent splenocytes and increased levels of that cytokine in cultures of peritoneal cells from mice and rats. This phenomenon may explain the costimulatory activity of phages in the model described.

16

Phage related conversion of enterotoxin A, staphylokinase and beta-toxin in Staphylococcus aureus

75%

Zabicka D. , Mlynarczyk A. , Windyga B. , Mlynarczyk G.

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nr 3-4

17

The delayed early gene G23 of temperate mycobacteriophage L1 regulates the expression of deoxyribonuclease, the product of another delayed early gene of the phage

75%

Mandal P. , Datta H. J. , Sau S. , Mandal N. C.

Polish Journal of Microbiology

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2008

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tom 57

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nr 2

EN

To get clues about the genes as well as the gene regulatory circuit controlling the lytic development of temperate mycobacteriophage L1, previously we screened several conditional lethal mutants of L1 and characterized some of them to an extent. One of the mutants, L1 G23ts23, was found defective in both growth and late gene transcription at 42°C but not at 32°C. Here we show that the above phage mutant is also defective in the expression of phage-coded deoxyribonuclease (DNase) at 42°C but not at 32°C. The G23 gene however does not code for the above enzyme. Further analyses using the L1 G23ts23 mutant suggest that synthesis of DNase is also not regulated by G23 at transcriptional level. Expression of functional DNase in fact requires de novo protein synthesis. Among the 25 revertants isolated from the L1 G23ts23 mutant, which are capable of growing at 42°C (by overcoming the ts defect in late transcription), two, R4 and R22, have been shown to retain the ts defect in the expression of the above enzyme and R4, to retain also the G23ts23 mutation. This suggests that R4 (R22 was not tested for the presence of G23ts23 mutation) carries an extragenic suppressor of G23ts23 mutation in a different gene (we call this putative gene as Gx), which now helps bypass the requirement of G23 for late gene transcription. Possible role of G23 on the regulation of L1-coded Gx and deoxyribonuclease has been discussed at length.

18

Expression of genes 51, 27, 28 coding for proteins of the central part of bacteriophage T4 baseplate in the bacteriophage T7 promoter-RNA polymerase expression system

75%

Nieradko J. , Podgorska B.

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1993

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tom 40

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nr 2

XX

A fragment of T4 DNA (XbaI-HindIII) comprising the genes 51,27,28, which encodes the central plug proteins was cloned into plasmid pT7-5 and p7-6 (T7 RNA polymerase expressing system). The examined genes were only overexpressed when the orientation of cloned DNA to promoter <1>10 was as follows: promoter 10 and genes 51, 27, 28. This was achieved when the fragment (Xbal-Hindlll) was cloned into plasmid pT7-5. Gene 27 and 28 were overexpressed when the intact fragment (Xbal-Hindlll) was used. The high rate of the synthesis of proteins 27 and/or 28 had a strong inhibitory effect on the level of synthesis of the product of gene 51. For the overexpression of gene 51 in this system a deletion derivate which was devoid of gene 28 and a larger fragment of gene 27 was prepared.

19

Sensitivity of Vi phages III to gamma-radiation in the presence of cisplatin

75%

Dabrowski T. , Kwiatkowski B.

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2005

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tom 52

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nr 2

EN

In this study we determined Vi bacteriophage III sensitivity to native cisplatin, γ radiation (60Co) or to irradiated cisplatin, and checked the possibility of enhanced Vi bacteriophage III inactivation under combined exposure to cisplatin and γ radiation. We used highly purified phage suspensions in 0.9% NaCl solution or phosphate-buffered saline. Phage suspensions were titrated using a double agar layer method. Our study implies that survival of Vi bacteriophage III shows an exponential inverse correlation with cisplatin concentration in the incubation medium and the time of phage incubation in the presence of cisplatin. The use of irradiated cisplatin reduces phage survival in comparison with suspensions containing non-irradiated cisplatin. Irradiation of phage suspension with cisplatin causes a significant increase of phage inactivation in comparison with either treatment alone. Our results suggest that presence of cisplatin in irradiated medium enhances the radiobiological effect on Vi bacteriophages III.

20

Phage therapy: a reappraisal of bacteriophages as antibiotics

75%

Inal J. M.

Archivum Immunologiae et Therapiae Experimentalis

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2003

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tom 51

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nr 4