Natural Preservation of Corpses of 'Paramecium Aurelia' in Cultures of a Suctorian.

摘要

Natural preservation of corpses of Paramecium aurelia in cultures of a suctorian. Trans. Amer. Micros. Soc., 95: 637-645. Dense, brownish, nonmotile forms of Paramecium aurelia were formed and preserved on three separate occasions in cultures in which paramecia were used as food for the suctorian Heliphrya erhardi. Some suctorians were also preserved. Many of these altered cells remained intact for more than six months. Transmission and scanning electron microscopy established that these forms were dead ciliates, in which organelles and membranes were preserved in slightly altered forms but in nearly normal anatomic arrangement. The preserved cells contained a few bacteria, and soluble materials appeared to have been lost. It is not clear why normal decay processes failed to remove these corpses, but some possibilities are considered. One testable hypothesis postulates that the filamentous actinomycetes seen on the surface of the cultures are similar to organisms known to cause bulking in activated sludge and that they may be retarding decay of the ciliates. (Author)