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A new laboratory cultivation of Paramecium bursaria using non-pathogenic bacteria strains
1Department of Microbiology, Institute of Biology, Pedagogical University of Cracow, Podbrzezie 3, 31-054 Kraków, Poland. tbator@ap.krakow.pl
Abstract:
In most studies dealing with the laboratory cultivation of paramecia (Paramecium bursaria), Klebsiella pneumoniae bacteria are used to inoculate the medium. However, Klebsiella pneumoniae is a typical pathogen, and its use is always associated with a risk of infection. The aim of the present research was to examine non-pathogenic bacteria strains as components of the medium for Paramecium bursaria. The paramecia were incubated on lettuce infusions bacterized with different bacteria strains: Bacillus subtilis DSM 10, Bacillus megaterium DSM 32, Escherichia coli DSM 498, Micrococcus luteus DSM 348. A strain derived from the natural habitat of Paramecium bursaria was used as the control one. Experiments were conducted under constant light and in the dark. Paramecia cells were counted under a stereomicroscope on consecutive days of incubation. The obtained results show that the most intensive growth of Paramecium bursaria occurs in the presence of Escherichia coli DSM 498. The use of this strain as a component of the medium allows one to obtain a high number of ciliates regardless of the light conditions. It can be concluded that the Paramecium bursaria cultivation procedure can be modified by using the non-pathogenic bacteria strain Escherichia coli DSM 498 instead of Klebsiella pneumoniae.
Insights
Researchers explored non-pathogenic bacteria for cultivating Paramecium bursaria, finding Escherichia coli DSM 498 promotes intensive ciliate growth. This offers a safer alternative to the pathogenic Klebsiella pneumoniae for laboratory paramecia cultures.
Area of Science:
- Microbiology
- Protozoology
- Aquatic biology
Background:
- Laboratory cultivation of Paramecium bursaria typically uses Klebsiella pneumoniae.
- Klebsiella pneumoniae is a pathogen, posing infection risks in research settings.
- There is a need for safer, non-pathogenic bacterial alternatives for Paramecium bursaria culture.
Purpose of the Study:
- To evaluate non-pathogenic bacterial strains as a safe and effective medium for Paramecium bursaria cultivation.
- To compare the growth-promoting capabilities of different bacterial strains on Paramecium bursaria.
- To determine the optimal bacterial strain for Paramecium bursaria laboratory culture.
Main Methods:
- Paramecium bursaria were incubated in lettuce infusions inoculated with various non-pathogenic bacteria: Bacillus subtilis DSM 10, Bacillus megaterium DSM 32, Escherichia coli DSM 498, and Micrococcus luteus DSM 348.
- A control group used a bacterial strain from the natural habitat of Paramecium bursaria.
- Experiments were conducted under constant light and dark conditions, with daily cell counts using a stereomicroscope.
Main Results:
- Paramecium bursaria exhibited the most intensive growth when cultured with Escherichia coli DSM 498.
- High numbers of Paramecium bursaria were achieved using Escherichia coli DSM 498, irrespective of light conditions.
- Other tested non-pathogenic strains supported Paramecium bursaria growth to varying degrees.
Conclusions:
- Escherichia coli DSM 498 is a suitable non-pathogenic alternative to Klebsiella pneumoniae for Paramecium bursaria laboratory cultivation.
- The use of Escherichia coli DSM 498 can enhance the safety and efficiency of Paramecium bursaria culture protocols.
- This finding allows for modified cultivation procedures, reducing infection risks in protozoological research.

