New ultrastructural data on the microsporidian Ichthyosporidium giganteum infecting the marine teleostean fish Ctenolabrus rupestris (L.) (original) (raw)
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The Ultrastructure of Spores (Protozoa: Microsporida) from Lophius americanus , the Angler Fish 1
The Journal of Protozoology, 1986
Spinal and cranial ganglia of American angler fish, Lophius umericunus, arc often infected with microsporidia. This protozoon elicits the formation of large, spore-filled, hypertrophied host cells, cysts. Previous reports of microsporidia in European lophiids identify the parasite as S p r u p u lophii, a genus which has recently been shown to be dimorphic. The spores from L. umericunur are monomorphic (2.8 x 1.5 pm) and uninuclcate. Each spore contains a polar tube that forms six to nine coils. Sprugueu Iophii differs from the microsporidium described in L. umericunus in several ways. Sprugueu lophii has two spore types: a large spore (4.0 x 1.25 pm) containing a diplokaryon and thrcc to four polar tube coils and a smaller uninucleate spore (3.5 x 1.5 pm) with five to six polar tube coils. Because of these major differences, the microsporidium from L. umericunus is removed from the genus Sprugueu and returned to its original genus, Glugeu, as a new species, G. umericunus n. sp. Other ultrastructural characteristics of G. umericunus are included: the posterior vacuole encloses two distinct membranous structures; one is tubular and resembles a "glomerular tuft" and the m n d is lamellar and composed of concentric membrane whorls, additionally, the straight or manubroid portion of the polar tube proceeds beyond the posterior vacuole before it turns anteriorly and begins to coil. ERVE cells from the spinal and cranial ganglia of European N lophiid (angler) fishes, Lophius budegassa and L. piscaforius, are often infected with microsporidia that produce cell hypertrophy cysts (24). Because of the similarity of these cysts with those produced by Microsporida in the genus Glugea, the parasite was originally identified as Glugea Iophii Doflein, 1898. This organism was subsequently transferred into the genus Nosemu (23) where it remained until 1976. when a new genus, Spruguea. was established for it (24). A dimorphic develop
2009
Precipitated by unexpected discoveries, this thesis is dedicated to the study of the biology of ichthyosporeans. While searching for undiscovered opisthokonts living osmotrophically in marine invertebrate digestive tracts, I established 177 cultures of ichthyosporeans. Ichthyosporeans are one of six understudied unicellular lineages related to the multicellular animals and fungi. Ichthyosporeans are comprised of approximately 30 genera but, prior to this thesis, only four genera had been cultivated. I identified and described three new genera and six species using microscopy and molecular phylogenetic techniques. Two, which I named Abeoforma whisleri and Pirum gemmata, were most closely related to divergent clone sequences and had no known relatives. My other four species, each isolated between eight and 126 times, were related to single isolates Sphaeroforma arctica and Pseudoperkisus tapetis, also found in marine invertebrates. I described one as the new genus and species Creolimax fragrantissima because of its amoeboid reproductive and dispersal stage and fragrance. The other three species were closely related and morphologically indistinguishable. To delimit species, I sequenced three loci from multiple isolates and applied a genealogical concordance species concept. Once delimited, I was able to describe variations in life cycle, morphology and a possible difference in host preference. Rather than adapt cytological techniques to describe the life cycle of S. tapetis, the most abundant species, I used population genetics to work in reverse. Absence of heterozygotes provided evidence for haploidy. Phylogenetic incongruence and a lack of support for linkage between two loci signified a history of recombination consistent with a sexual cycle. I described the ultrastructure of five species using high-pressure frozen cells from healthy, luxuriantly growing cultures. The quality of preservation allowed me to describe features that were new to ichthyosporeans, such as, spindle pole bodies and tubular extensions of the cell that penetrated the cell wall. These features were found in both clades and may have been present in the ancestral ichthyosporean. By combining genetic evidence for sex, observations of asexual reproduction in culture and collection frequencies I proposed a life cycle involving infrequent recombination within a predominantly asexual organism that infected invertebrate hosts indiscriminately via asexual endospores.
J Eukaryot Microbiol, 1970
SYNOPSIS. Telomyxa glugeiformis found in France is structurally identical with the same parasite from Romania. The electron microscope shows that the sporonts in the fat body cells of Ephemera danica develop a double membrane. Electron-opaque material (which is the polar ring of the future diplospore) is deposited at the opposite poles of the sporont in the space between the 2 membranes. The cell division which follows leads microsporidan Telomyxa glugeiformis was discov-Ephemera vulgata larvae in France. They correctly recognized the microsporidan nature of this parasite. At the same time they realized that the spores of Telomyxa differ considerably from those of other Microsporida because they have 2 polar filaments rather than one.
Parasitology Research, 2009
The life cycle of a new microsporidian of the genus Pleistophora is described. This parasite infects the epithelial cells of the gut and the peritoneal cavity of the Red Sea fish, Epinephelus chlorostignei. All stages develop within a special structure, the sporophorocyst, which is covered by a thick dense wall. This wall grows along with the growth of the parasites inside. Meronts are uni-to binucleate, which divide and constantly give rise to sporonts. During transition to sporonts, the cell border of the meronts increases its thickness, temporarily featuring thick irregular projections. Eventually, a uniform thick sporont wall is formed; then, the sporont cells detach themselves from the wall (future wall of the sporophorous vesicle, SPV) and start a series of divisions to produce sporoblasts. The SPV wall is compact, has no pores, and consists of two layers. Mature spores measure about 2.0× 1.8 µm. They possess a polar filament with 20-28 coils, a posterior vacuole, and a polaroplast made up of an outer part of dense and closely spaced lamellae encircling an inner part of widely spaced lamellae. All morphological and ultrastructural features indicate that the described microsporidian parasite belongs to the genus Pleistophora.
Journal of Invertebrate Pathology, 1987
A new species of a microsporidan, Abelsporu porfuculensis, was found in the hepatopancreas of Curcinus maenas. forming white xenomas. Each xenoma seems to consist of an aggregate of hypertrophic host cells in which the parasite develops and proliferates. This cytozoic microsporidan being characterized by one uninucleate schizont giving rise to two sporonts. each originating two sporoblasts, resulting in two spores within a persistent sporophorous vacuole (pansporoblast) should be included in a new family Abelsporidue. In fresh smears most spores were 3.1-3.2 pm long and I.?-1.4 km wide. Fixed, stained, and observed in SUS mature spores measured 3.1 z 0.08 x 1.3 t 0.06 pm (n = 25 measurements). Spore cytoplasm was dense and granular. polyribosomes were arranged in helicoidal tape form. The polar filament was anisofilar and consisted of a single coil with 5-6 turns. The anchoring disc and and the anterior zone of the filament are surrounded by the polaroplast composed of two usual zones. In the anterior zone, the membrane of the polar filament is in continuity with the membranes of the polaroplast. The appearance of a microsporidan with described nuclear divisions in life cycle. spores shape and size. polaroplast and polar filament morphology and identity of the host suggests that we may erect a new genus Abe/sporu and a new species A. portucalensis (Portugal = Portucalem).
The Journal of Protozoology, 1970
SYNOPSIS. Telomyxa glugeiformis found in France is structurally identical with the same parasite from Romania. The electron microscope shows that the sporonts in the fat body cells of Ephemera danica develop a double membrane. Electron-opaque material (which is the polar ring of the future diplospore) is deposited at the opposite poles of the sporont in the space between the 2 membranes. The cell division which follows leads microsporidan Telomyxa glugeiformis was discov-Ephemera vulgata larvae in France. They correctly recognized the microsporidan nature of this parasite. At the same time they realized that the spores of Telomyxa differ considerably from those of other Microsporida because they have 2 polar filaments rather than one.
Ichthyosporidium weissii n. sp. (Microsporidia) Infecting the Arrow Goby (Clevelandia ios)
Journal of Eukaryotic Microbiology, 2012
Gonadal infections by a novel microsporidium were discovered in 34% (13/38) of arrow gobies, Clevelandia ios, sampled over a three year period from Morro Bay Marina in Morro Bay, California. Gonadal tumors had been reported in arrow gobies from this geographic area. The infected gonads, found primarily in females, typically appeared grossly as large, white-gray firm and lobulated masses. Histological examination revealed large, multilobate xenomas within the ovaries and no evidence of neoplasia. Typical of the genus Ichthyosporidium, the large xenomas were filled with developmental stages and pleomorphic spores. Wet mount preparations showed two general spore types: microspores with mean length of 6.2 (7.0-4.9, SD = 0.6, N = 20) μm and mean width of 4.3 (5.3-2.9, SD = 0.8) μm; and less numerous macrospores with mean length of 8.5 (10.1-7.1, SD = 1.0, N = 10) μm and mean width of 5.5 (6.2-4.8, SD = 0.5) μm. Transmission electron microscopy demonstrated stages consistent with the genus and 35-50 turns of the polar filament. Small subunit (SSU) rDNA gene sequence analysis revealed that the parasite from arrow gobies was most closely related to, but distinct from Ichthyosporidium sp. based on sequences available in GenBank. We conclude that this microsporidium represents a new species of Ichthyosporidium, the first species of this genus described from a member of the family Gobiidae and from the Pacific Ocean.