All posts by Postępy Mikrobiologii

Postępy badań nad bakteriami rodzaju Listeria

Progress in research on the genus Listeria
K. B. Muskalska, B. Szymczak
25 July 2017

1. Wstęp. 2. Charakterystyka rodzaju Listeria. 2.1. Filogenetyczne pokrewieństwo pomiędzy gatunkami rodzaju Listeria. 2.2. Serotypy. 2.3. Geny charakterystyczne dla Listeria sp. 2.3.1. Mechanizmy wirulencji L. monocytogenes. 2.4. Chorobotwórczość L. monocytogenes. 3. Szczepy atypowe. 3.1. Szczepy atypowe wyizolowane z sera. 3.2. Atypowa niehemolityczna L. seeligeri. 3.3. Atypowa hemolityczna L. innocua. 3.4. L. marthii. 3.5. L. rocourtiae. 3.6. L. weihenstephanensis. 3.7. L. fleischmannii. 4. Podsumowanie

Abstract: The Listeria-like atypical strains have been identified in the natural environment and in the food samples lately. In recent times, Listeria monocytogenes isolates were characterized for molecular serogroup identification by multiplex PCR. Subsequently, virulence genes were detected. The results of the study show that the presence or absence of some virulence genes depends on the serotype of L. monocytogenes. The phylogenetic position and phenotypic character of isolated strains similar to Listeria spp. were studied. The atypical strains were examined based on diagnostic tests (hemolysis, CAMP, sugar fermentation, motility at 25°C) commonly used to identify Listeria. The isolates were highly similar phenotypically. The rrs gene sequence (encoding 16S rRNA) was analyzed in comparison to the genus Listeria. 16S rRNA sequencing data showed that these strains belong to the genus Listeria, but were different from all other known species. Phylogenetic distance from six known species of the genus Listeria indicated that they represent a novel species. The names Listeria marthii, Listeria rocourtiae, Listeria weihenstephanensis and Listeria fleischmannii were proposed for the four novel species isolated from samples obtained from the natural environment and food. Moreover, the presence of natural atypical hemolytic Listeria innocua strains and natural atypical nonhemolytic Listeria seeligeri isolates was observed. These strains differed from known L. innocua and L. seeligeri in only one of the hly gene.

1. Introduction. 2. Characterization of the genus Listeria. 2.1. Phylogenetic relation between species of the genus Listeria. 2.2. Serotypes. 2.3. The specific genes of the Listeria sp. 2.3.1. Mechanisms of virulence of L. monocytogenes. 2.4. Diseases associated with L. monocytogenes. 3. Atypical strains. 3.1. Atypical strains isolated from cheese. 3.2. Atypical nonhemolytic L. seeligeri strains. 3.3. Atypical hemolytic L. innocua strains. 3.4. L. marthii. 3.5. L. rocourtiae. 3.6. L. weihenstephanensis. 3.7. L. fleischmannii. 4. Summary

Autor: Postępy Mikrobiologii
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Probiotyki a wybrane schorzenia u ludzi

Probiotics and the selected diseases in humans
B. Tokarz-Deptuła, J. Śliwa-Dominiak, M. Adamiak, W. Deptuła
25 July 2017

1. Wprowadzenie. 2. Probiotyki, a wybrane schorzenia u ludzi. 2.1. Biegunki. 2.2. Alergie. 2.3. Procesy nowotworowe. 2.4. Infekcje wirusem HIV. 3. Podsumowanie

Abstract: Probiotics are supplements or foods based on microorganisms isolated from the gastrointestinal tract of healthy humans. They have a highly positive effect on macroorganisms reducing the risk of potential pathogenic bacterial growth and influencing the host immune response. It has been proved that the microflora in the digestive tract ecosystem is conditioned by the presence of diarrhea and allergies Also other disorders, recorded already in the neonatal period, when the immune system was differentiating in the direction of pro-inflammatory and/or pro-alergic, can have an impact on the microflora. The administration of probiotic microorganisms and (or) chemotherapeutic agents, including antibiotics, improves the quality of the therapy because it results in the restoration of the balance between pro-and anti-inflammatory response of the gastrointestinal tract in such diseases as diarrhea, allergies, tumor processes, as well as in viral infections, including HIV infection.

1. Introduction. 2. Probiotics and the selected diseases and infections in humans. 2.1. Diarrhea. 2.2. Allergy. 2.3. Cancer processes. 2.4. HIV infection. 3. Summary

Autor: Postępy Mikrobiologii
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Bakterie kwasu mlekowego (LAB) jako wektory do konstrukcji szczepionek

LAB (lactic acid bacteria) as live vectors for the development of safe mucosal vaccines
A. Wyszyńska, P. Kobierecka, E. K. Jagusztyn-Krynicka
25 July 2017

1. Charakterystyka bakterii kwasu mlekowego o potencjalnym zastosowaniu w immunoprofilaktyce. 2. LAB jako nośniki heterologicznych antygenów bakteryjnych, pasożytniczych i wirusowych. 2.1. Porównanie drogi podania. 2.2. Rola lokalizacji i ilości antygenu. 2.3. Porównanie skuteczności działania żywych szczepów LAB i cząstek GEM (Gram-positive Enhancer Matrix). 3. LAB jako szczepionki DNA. 4. Modulacja działania układu odpornościowego. 5. LAB w immunoterapiach chorób nowotworowych. 6. Podsumowanie

Abstract: 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 increasing interest in the use of LAB as mucosal delivery vectors. They represent an attractive alternative for vaccinations employing attenuated bacterial pathogens. In this review, we focused on recent results on the use of lactic acid bacteria as delivery vehicles for heterologous antigens, cytokines, and DNA vaccines. To date, many bacterial, parasitic and viral antigens have been successfully expressed in LAB strains, mainly in L. lactis and Lb. plantarum, and their positive immunological outcomes were documented using mainly mouse model and oral, intragastric or intranasal route of immunization.

1. Characterization of lactic acid bacteria with immunoprophylactic effects. 2. LAB as delivery vehicles for bacterial, parasitic and viral antigens. 2.1. Comparison of administration routes. 2.2. Amount and localization of antigens. 2.3. Comparison of live and killed LAB vaccines – GEM (Gram-positive Enhancer Matrix) particles, 3. LAB as a DNA vaccine. 4. Modulation of immune system. 5. LAB in cancer therapy. 6. Conclusions

Autor: Postępy Mikrobiologii
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Bakterie Xenorhabdus i Photorhabdus, nicienie entomopatogeniczne i owady – funkcjonowanie w złożonym układzie symbiont – pasożyt – żywiciel

Bacteria Xenorhabdus and Photorhabdus, entomopathogenic nematodes and insects – their role in the complex symbiont-parasite- -host relationship
K. Kucharska, D. Kucharski, B. Zajdel
25 July 2017

1. Wprowadzenie. 2. Powstawanie pasożytnictwa nicieni u owadów. 3. Funkcjonowanie układu nicienie entomopatogeniczne – bakterie mutualistyczne – owady. 4. Mechanizmy odpornościowe owadów. 4.1. Odporność fizjologiczna: behawioralna. 4.2. Odporność fizjologiczna: bariery anatomiczno-fizjologiczne. 4.3. Odporność nabyta: polipeptydy i białka odpornościowe. 4.4. Odporność wewnętrzna: komórkowa i humoralna. 5. Mechanizmy odpornościowe nicieni entomopatogenicznych i mutualistycznych bakterii. 6. Podsumowanie

Abstract: Bioinsecticides based on nematodes are becoming increasingly popular agents for pest control. Nematodes used in these insecticides owe their properties to the presence of symbiotic bacteria. Representatives of two genera – Xenorhabdus and Photorhabdus can be found in the digestive tracts of, respectively, Steinernematidae and Heterorhabditidae nematodes. Nematodes have a number of properties, allowing them to penetrate the host integument, breaking the immune defenses, multiplicating in his body, killing the host and finally producing invasive forms, viable in the external environment. Bacterial symbionts are responsible for some of these abilities, since they produce toxins lethal to the victim and maintain adequate conditions for the development of their vectors. The bacteria are an example of one organism living in another as a symbiont, and functioning as a pathogen for another one. The relationship nematodes-mutualistic bacteria-insect is formed. The immune system has the ability to fight against insect entomopathogens, however, a variaty of adaptation mechanisms of parasites and symbionts, molecular mimicry and destruction of phagocytic cells among others, enables them to survive in the host. With an effective biocidal properties, nematodes which are in a mutualist relationship with bacteria, become perfect and safe for use in the environment pest control agents. Transgenic plants producing Xenorhabdus and Photorhabdus toxins can be as effective as those producing Bacillus thuringiensis toxins.

1. Introduction. 2. The emergence of nematode parasitism in insects. 3. System functioning of entomopathogenic nematodes-mutualistic bacteria-insects. 4. Defense mechanisms of insects. 4.1. Physiological resistance: behavioral aspect. 4.2. Physiological resistance: anatomical-physiological barriers. 4.3. Acquired immunity: polypeptides and immune proteins. 4.4. Internal resistance: cellular and humoral factors. 5. Immune mechanisms of entomopathogenic nematodes and mutualist bacteria. 6. Summary

Autor: Postępy Mikrobiologii
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ECA – wspólny antygen powierzchniowy pałeczek rodziny Enterobacteriaceae

ECA – common surface antigen of the bacilli of the Enterobacteriaceae family
K. Kasperkiewicz, M. Noszczyńska, A. Piszczek
25 July 2017

1. Historia odkrycia. 2. Występowanie. 3. Charakterystyka chemiczna. 4. Formy ECA. 5. Biosynteza i jej kontrola genetyczna. 6. Właściwości immunogenne. 7. Lokalizacja ECA w komórce bakteryjnej i sposoby jego detekcji. 8. Rola biologiczna. 9. Zastosowanie. 10. Podsumowanie

Abstract: Almost all the strains of bacteria belonging to the Enterobacteriaceae family share at least one common antigenic component, ECA, which is not present in other Gram-negative and Gram-positive bacteria. From the observations made with immunofluorescence and immunoferritin techniques, it has been concluded that ECA is localized in the outer leaflet of the outer membrane of Gram-negative enteric bacteria. ECA is a glycolipid consisting of linear trisaccharide repeating units composed of [→3)-α-D-Fucp4NAc-(1→4)-β-D-ManpNAcA-(1→4)-α-D-GlcpNAc-(1→]. It occurs in three structural forms: ECAPG linked to phosphatidylglycerol, ECALPS anchored to LPS core region and ECACYC not expressed on the surface. ECA is believed to be connected to the LPS outer core. However, it should be emphasized that Yersinia enterocolitica serotype O:3 mutants defective in outer core synthesis were also ECA-immunogenic. The genes involved in ECA biosynthesis are located in the chromosomal wec gene cluster, from wecA to wecG and the ECA expressions is downregulated at host temperature. So far, ECA has been thoroughly analyzed at the structural and genetic level, however, its significance in vivo has been investigated in relatively few studies. ECA has been linked to pathogenesis in several species of bacteria, although this function seems to differ between the species. ECA has been shown to be involved in the flagellar assembly and motility in Serratia marcescens. Also, the ECA-negative mutants of Salmonella enterica serovar Typhimurium proved to be significantly less virulent than the parental strain. ECA as a marker of Enterobacteriaceae family is a valuable indicator of water and food contaminations with enteric bacteria.

1. Discovery history. 2. Occurrence. 3. Chemical characterization. 4. Forms of ECA. 5. Genetics of ECA biosynthesis. 6. The immunogenic properties. 7. Localization of ECA in the bacterial cell and methods of its detection. 8. Biological significance. 9. Application. 10. Summary

Autor: Postępy Mikrobiologii
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Advancements of Microbiology
Volume 63 (2024): Issue 3

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