Ref ID : 7535
Guy Brugerolle, Jiri Lom, Eva Nohynkova, and Louis Joyon; [Comparison et Evolution des Structures Cellulaires chez Plusieurs Especes de Bodonides et Cryptobiides Appartenant aux Genres Bodo, Cryptobia et Trypanoplasma (Kinetoplastida, Mastigophora)]. Protistologica XV(2):197-221, 1979
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Transmission and scanning electron microscope studies of at least 5 species of free-living and ecto or endo parasites Bodonids and Cryptobiids (Bodo sp. a species close to Bodo caudatus, Cryptobia branchialis from the gills of fish, Cryptobia dahlii and Cryptobia intestinalis from the stomach of marine fishes, Cryptobia helicis from seminal vesicle of snails and Trypanoplasma borreli from the blood of Cyprinus carpio) have been compared. A1 these Flagellates possess 2 flagella, one anteriorly directed, the other recurrent, both arizing from a broad flagellar pocket; they share the same structure as other Kinetoplastids but peculiar structures have been observed. The cytoskeleton is composed of 3 kinds of fibers attached to or near the kinetosomes a) the dorsal system (Fd) comprising 3 microtubules coupled to a dense lamina which runs along the dorsal and right edge of the flagellar pocket and from which arises the dorsal sheet of linked microtubules going to the posterior tip beneath the membrane, b) the ventral fiber (Fv) formed by 5 microtubules runs along the left side of the flagellar pocket, turns backward and enlarges on the ventral face in front of the recurrent flagellum, c) the cytostomal fiber composed of reinforced microtubules (mtr) linked to the membrane runs along the bottom of the flagellar pocket then it forms a preoral crest (Cr) coated by fine filaments before to turn backward and to penetrate deeply into the cytoplasm of the right cell side to form the tubular cytopharynx. In Cryptobia helicis and Trypanoplasma the preoral crest is very elongated and the cytopharynx opens behind the nucleus near the middle of the cell, d) associated microtubular fibers and periodic plates complete the armature of the cytostome-cytopharynx and differentiate the species. The corset of microtubules is always incomplete and divided in a large dorsal and a narrow ventral sheet in front of the recurrent flagellum. The recurrent flagellum is poorly attached to the ventral surface in Bodo sp. but strongly adherent in Cryptobia and Trypanoplasma, in Cryptobia branchialis the recurrent flagellum adheres to the cells of gill, in Cryptobia helicis and Trypanoplasma it forms an undulating membrane with a fold of the cell body. A1 these cells present a kinetoplast, containing large amount kDNA fibrils branched to the mitochondria at the base of the kinetosomes. In the trophozoite Bodo sp. kDNA fibrils are dispersed in the branches of the mitocondrial matrix, in the precystic and cystic stages of kDNA forms nodules representing several kinetoplasts. We can also distinguish 3 different types of arrangement of kDNA fibrils: dispersed and reticulated fibrils, condensed and arched fibrils like crystals, many condensed bundles of fibrils embedded in a dense mitochondrial matrix. These observations are compared with those described in other Bodonina and Kinetoplastida already studied. There is a progressive structural transformation and evolution of the cells from the free living to the ecto and endo parasites. The digenetic Trypanoplasma from the blood transmitted by a leech vector with morphological changes must be separated from the monogenetic Cryptobia parasites in the Trypanoplasmatinae subfamily.