title: Ectosymbiotic bacteria on ciliated cells of a rotifer.
abstract: During the examination of Brachionus plicatilis (Rotifera, Monogononta), ectosymbiotic bacteria were found in the ciliated buccal region. These have about the same dimensions as the cilia and possess a specific apical region that apparently serves to attach the bacterium to its host cell. This apical region resembles a vesicle but is interpreted as a specialized region of the bacterial nucleocytoplasm devoid of ribosomes and chromatin strands but containing a crystalline rod. The bacterium has two membranes (as have other Gram-negative bacteria) also over the apical region. Thin strands join the two membranes and similar strands extend from the bacterium to the cell membrane of the host cell. No intracellular bacteria were found in this study.
authors.affiliation: Dipartimento di Biologia Evolutiva, Università di Siena, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Selmi
mesh_terms: D000818:Animals; D001419:Bacteria / Q000648:ultrastructure*; D002923:Cilia / Q000382:microbiology / Q000648:ultrastructure; D008854:Microscopy, Electron; D012403:Rotifera / Q000382:microbiology* / Q000648:ultrastructure; D013559:Symbiosis