Bacterial endocytobionts in the macronucleus of Frontonia leucas (Ciliophora, Peniculida)
Abstract:Despite the close relationship with the genus Paramecium, the species of which have a great variety of bacterial endocytobionts, a similar rich diversity of endocytobionts was not found in the genus Frontonia. This difference may probably be due to the different mode of feeding of the latter ciliates, which are chiefly algivorous. In this paper the first finding of microorganisms inside the nuclear apparatus of a Frontonia species is described. In a freshwater population of F. leucas bacteria were found in the macronuclei of almost 100% of specimens collected. Infected cells were investigated by light and electron microscopy. The endocytobionts show considerable variation of size: from 1 × 0.4 to 16 × 0.8 μm, some of the bacteria bearing a number of viral capsids. Certain of the bacteria showed cytoplasmic areas of different density. According to the results of in situ hybridization the bacteria belong to the alpha subgroup of proteobacteria. Simultaneously with the bacteria the host cells contained numerous Chlorella algae in the cytoplasm, which is not a common feature for F. leucas.
Document Type: Research Article
Affiliations: 1: Biological Institute, St. Petersburg State University, Oranienbaumskoye sch. 2, 198504, St. Petersburg, Russia;, Email: firstname.lastname@example.org 2: Biological Institute, University of Stuttgart, Pfaffenwaldring 57, 70569, Stuttgart, Germany
Publication date: 2003-09-01