| Autor: |
Fukuda, Takashi, Takenaka, Shoji, Kota, Kohichi, Iwaku, Masaaki, Hoshino, Etsuro |
| Předmět: |
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| Zdroj: |
Microbial Ecology in Health & Disease; Dec2004, Vol. 16 Issue 4, p205-210, 6p |
| Abstrakt: |
The aim of this study was to establish a method for quantitative differential counting of live/dead anaerobic microorganisms. Artificial biofilms of Peptostreptococcus anaerobius 4330-1, one of the strictest anaerobes, were made on filters of 0.4 μm pore size. A commercial Live/Dead BacLight Bacterial Viability Kit using propidium iodide (PI) and SYTO9 fluorescent staining was found to be suitable for the facultatively anaerobic organism Propionibacterium acnes . However, P. anaerobius seemed to reduce SYTO9 and change fluorescent intensity, which made the kit unsuitable for this anaerobe. As an alternative method suitable for even P. anaerobius , a combination of phase-contrast microscopy and PI staining was adapted. Bacterial numbers could be counted in phase-contrast microscopic fields, and PI-positive organisms were counted as dead organisms in the same field. Only 3.8% of P. anaerobius cells in artificial biofilms were found to be PI-positive after exposure to air for 24 h, while 44% of planktonic P. anaerobius cells were PI-positive after exposure to air for 24 h. Similarly, 38% of P. anaerobius cells were PI-positive when organisms were collected onto filters to make bacterial masses and thereafter exposed to air for 24 h. These results indicate that P. anaerobius is highly aerotolerant in biofilms. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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