Zroznicowanie agregacji komorek Enterococcus faecalis pAD1 [-] pod wplywem feromonu cAD1

• Autorzy: Jarzembowski T. , Bryl E. , Galinski J. , Witkowski J.M.

Warianty tytułu

EN

Flow cytometric analysis of Enterococcus faecalis pAD1 [-] strains response to cAD1 pheromone

• Języki publikacji: PL

Abstrakty

PL

Przy użyciu cytometru przepływowego zbadano wpływ feromonu cADl na szczepy Enterococcus faecalis pozbawione plazmidu pADl. Stwierdzono statystycznie istotną zmianę natężenia fluorescencji komórek barwionych kar- boksyfluoresceiną i stopnia agregacji pod wpływem cADl. Na podstawie wielkości różnic wyróżniono dwie grupy szczepów pAD(-).

EN

Conjugative plasrnids transfer in Enterococcus faecalis is inducted by sex pheromones. The pheromone is excreted by recipient cells and induces expression of aggregation protein AS in donor cells. This protein is involved in formation of matting aggregates. Use of flow cytometry and anti-As monoconal antibodies allowed collect of interesting data pheromone response. However, according to our knowledge, no study focused on unspecific influence on particular pheromone for plasmid -free recipient strains. Six pADl (-) and tree pADl (+) Enterococcus faecalis stains were cultivated for 18h in ВHI, with and without cADl pheromone (Sigma, Germany), respectively. The bacteria were washed, stained with carboksyfluorescein (FCDA, and analyzed by flow cytometry in FACS BD scan cytometr. Relative fluorescence and size of aggregation was used to compare influence on particular strains. Surprisingly, the results shows divergence in fluorescence, size of aggregates and degree of correlation between fluorescence of aggregates and their sizes among pADl(-) strains, allowing for distinguish of two groups. Three of studied strains have higher fluorescence than pAD (+) stains. Correlation between fluorescence and size of aggregates, significant higher than in pADl(+) stains, decrease from r = 0, 88 to r=0, 74 in reaction to cADl. The strains if other group fluorize with lower intensity than pADl(+). Furthermore, 30,4% pADl(-) of second group have no detectable fluorescence. In contrast to pADl(- ) strains of the first group and pADl(+) strains, low (r=0,55) correlation between fluorescence and size of aggregates of group II increase up to r=0,74 after incubation with cADl pheromone. Previous study of these pADl(-) strains, currently assigned to group II, shown their low frequency of collecting aph2" gene encoded on other conjugative plasmid, pMG. According to these results, such flow cytometric analysis may be used to predict ability of strain to collect unrelated conjugative plasmid.

Słowa kluczowe

PL

Enterococcus faecalis; koniugacja; feromony; plazmidy; feromon cAD1; plazmid pAD1; cytometria przeplywowa; agregacja komorek; zroznicowanie

• Wydawca: -
• Czasopismo: Medycyna Doświadczalna i Mikrobiologia
• Rocznik: 2005
• Tom: 57
• Numer: 3
• Opis fizyczny: s.263-268,rys.,tab.,bibliogr.

Twórcy

autor

Jarzembowski T.

• Akademia Medyczna w Gdansku, ul.Do Studzienki 38, 80-227 Gdansk

autor

Bryl E.

autor

Galinski J.

autor

Witkowski J.M.

Bibliografia

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