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Manal El Garhy - One of the best experts on this subject based on the ideXlab platform.
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ultrastructural study of the development of Pleistophora schubergi zwolfer 1927 protozoa microsporida in larvae of the spruce budworm choristoneura fumiferana and its subsequent taxonomic change to the genus endoreticulatus
Journal of Eukaryotic Microbiology, 1991Co-Authors: Ann Cali, Manal El GarhyAbstract:This study demonstrates that Pleistophora schubergi Zwolfer, 1927, a microsporidium originally isolated from the midgut epithelium of Nygmia phaeorrhoea Don (Euproctis chrysorrhoea L.) and Porthetria dispar L., and subsequently reported in several other insects including the spruce budworm, Choristoneura fumiferana (the host used in this investigation), does not belong in the genus Pleistophora Gurley, 1893. Pleistophora schubergi lacks the major features that are characteristic of Pleistophora typicalis, the type species of this genus. A comparison of ultrastructural observations reported for the type species of the genus Pleistophora, P. typicalis, and our observations of P. schubergi revealed significant differences. A thick (0.5 μm) amorphous coat, derived from parasite secretions and deposited external to the parasite plasmalemma, surrounds all developmental stages in P. typicalis. Double membranes, derived from host rough endoplasmic reticulum cisternae encircle the parasite plasmalemma of all developmental stages in P. schubergi. The sporophorous vesicle encases the spores in P. typicalis, and originates from the parasite-secreted coat that is present around meronts. In P. schubergi, the host endoplasmic reticulum cisternae form the envelope that surrounds the meronts. Moreover, the sporophorous vesicle envelope in P. typicalis persists around groups of spores, while in P. schubergi this envelope breaks easily to release the spores in the host cytoplasm. By comparing the characteristics of the microsporidium found in the spruce budworm with those of the recently created polysporous genera that sporulate within a vesicle, we found that P. schubergi does belong in the new genus Endoreticulatus Brooks et al. 1988, and consequently rename it Endoreticulatus schubergi (Zwolfer, 1927) n. comb.
Alison M. Dunn - One of the best experts on this subject based on the ideXlab platform.
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Parasite transmission and cannibalism in an amphipod (Crustacea)
International Journal for Parasitology, 2003Co-Authors: Calum Macneil, Nina J. Fielding, Kevin D. Hume, Melanie J Hatcher, Jaimie T. A. Dick, Alison M. DunnAbstract:In its freshwater amphipod host Gammarus duebeni celticus, the microsporidian parasite Pleistophora mulleri showed 23% transmission efficiency when uninfected individuals were fed infected tissue, but 0% transmission by water-borne and coprophagous routes. Cannibalism between unparasitised and parasitised individuals was significantly in favour of the former (37% compared to 0%). In addition, cannibalism between parasitised individuals was significantly higher than between unparasitised individuals (27% compared to 0%). Thus, parasitised individuals were more likely to be cannibalised by both unparasitised and parasitised individuals. We discuss the conflicting selective forces within this host/parasite relationship, the implications of parasite mediated cannibalism for host population structure and the impacts this may have on the wider aquatic community.
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Resolution of a taxonomic conundrum: an ultrastructural and molecular description of the life cycle of Pleistophora mulleri (Pfeiffer 1895; Georgevitch 1929).
The Journal of eukaryotic microbiology, 2003Co-Authors: R. S. Terry, Calum Macneil, Jaimie T. A. Dick, Judith E. Smith, Alison M. DunnAbstract:The classification of a microsporidian parasite observed in the abdominal muscles of amphipod hosts has been repeatedly revised but still remains inconclusive. This parasite has variable spore numbers within a sporophorous vesicle and has been assigned to the genera Glugea, Pleistophora, Stempellia, and Thelohania. We used electron microscopy and molecular evidence to resolve the previous taxonomic confusion and confirm its identification as Pleistophora mulleri. The life cycle of P. mulleri is described from the freshwater amphipod host Gammarus duebeni celticus. Infection appeared as white tubular masses within the abdominal muscle of the host. Light and transmission electron microscope examination revealed the presence of an active microsporidian infection that was diffuse within the muscle block with no evidence of xenoma formation. Paucinucleate merogonial plasmodia were surrounded by an amorphous coat immediately external to the plasmalemma. The amorphous coat developed into a merontogenetic sporophorous vesicle that was present throughout sporulation. Sporogony was polysporous resulting in uninucleate spores, with a bipartite polaroplast, an anisofilar polar filament and a large posterior vacuole. SSU rDNA analysis supported the ultrastructural evidence clearly placing this parasite within the genus Pleistophora. This paper indicates that Pleistophora species are not restricted to vertebrate hosts.
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Differential drift and parasitism in invading and native Gammarus spp. (Crustacea: Amphipoda)
Ecography, 2003Co-Authors: Calum Macneil, Melanie J Hatcher, Jaimie T. A. Dick, Alison M. DunnAbstract:Invading and native species often interact directly, such as by predation, producing patterns of exclusion and coexistence. Less direct factors, such as interactions with the broader abiotic and biotic environment, may also contribute to such patterns, but these have received less recognition. In Northern Ireland, the North American Gammarus tigrinus has invaded freshwaters populated with the native Gammarus duebeni celticus, with intraguild predation between the two implicated in their relative success. However, these species also engage in day and night “drifting”, an activity that subjects amphipods to intense predation from fish and wildfowl. Sampling of two rivers where the invader and native co-occur showed that, compared with the benthos, G. tigrinus was underrepresented and G. d. celticus overrepresented in the drift. In addition, G. tigrinus were free from parasites, whereas some G. d. celticus harboured the acanthocephalans Polymorphus minutus and Echinorhynchus truttae and the muscle wasting microsporidian Pleistophora sp. (new species). Compared with the benthos, G. d. celticus parasitized with P. minutus were overrepresented and unparasitized individuals underrepresented in the drift. The opposite pattern was found with Pleistophora sp. In laboratory experiments, G. tigrinus were less positively phototropic and less “active” than G. d. celticus (unparasitized animals). Polymorphus minutus increased G. d. celticus positive phototropism and activity, while Pleistophora sp. increased positive phototropism but decreased activity. Previous studies show that the invader G. tigrinus is more disadvantaged by intraguild predation from the native G. d. celticus than vice versa. However, the native appears more disadvantaged with respect to drift, parasitism and the interaction of the two. These factors may mitigate direct interactions and help explain complex patterns of coexistence between these invader and native species.
Kareem Morsy - One of the best experts on this subject based on the ideXlab platform.
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Ultrastructure and molecular phylogenetics of a new isolate of Pleistophora pagri sp. nov. (Microsporidia, Pleistophoridae) from Pagrus pagrus in Egypt.
Parasitology Research, 2012Co-Authors: Kareem Morsy, A.-r. Bashtar, F. Abdel Ghaffar, Heinz Mehlhorn, Rewaida Abdel-gaberAbstract:The spore morphology and molecular systematic of a new microsporidian which was isolated from the common sea bream Pagrus pagrus (F: Sparidae Linnaeus, 1758) from the Red Sea, Egypt have been studied. Fifty-six out of 300 (18.7 %) of this fish were infected with microsporidian parasites. The infection was appeared as whitish, ellipsoid, round, or elongated nodules embedded in the epithelial lining of the peritoneum and also in the intestinal epithelium. Light microscopic study revealed that nodules were encapsulated by a fibrous layer encircling numerous mature spores measuring 1.7 ± 0.6 (1.5–2.7 μm) × 1.5 ± 0.3 μm (1.2–1.8 μm) in size. Ultrastructure of spores was characteristic for the genus Pleistophora: dimorphic, uninucleate spores (each spore possesses three to five polar filament coils) and a posterior vacuole. Also, the early recognizable stages of the parasite within nodules include uninucleated, binucleated, and multinucleated meronts followed by detachment of the plasmalemma of the sporont producing sporoblasts which mature to spores that consist of a spore coat and spore contents. Also, we analyzed the small subunit ribosomal gene (SSUrDNA) using PCR and sequencing specimens from the marine populations of P. pagrus fish from the Red Sea. From blast searches, sequence analysis, and phylogenetic analysis, we did not find corresponding GenBank entries to our species. Comparison of the nucleotide sequences showed that the sequence of our microsporidium was most similar to five Pleistophora species with degrees of identity (>91.5 %). It was most similar (97.8 % identity) to that of Pleistophora hyphessobryconis (account no. GU126672) differing in 19 nucleotide positions and with lower divergence value, Pleistophora ovariae (96.2 % identity, account no. AJ252955), Pleistophora hippoglossoideos (91.9 % identity, account no. AJ252953), Pleistophora mulleri (91.9 % identity, account no. EF119339), and Pleistophora typicalis (91.9 % identity, account no. AJ252956). So, they likely represent new species named Pleistophora pagri sp. n. with accession number JF797622 and a GC content of 53 %.
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Morphological and molecular biological characterization of Pleistophora aegyptiaca sp. nov. infecting the Red Sea fish Saurida tumbil
Parasitology Research, 2012Co-Authors: F. Abdel Ghaffar, A.-r. Bashtar, Heinz Mehlhorn, Kareem Morsy, Saleh Al-quraishy, Khaled Al-rasheid, Rewaida Abdel-gaberAbstract:One hundred three out of 225 (45.8%) of the Red Sea fish Saurida tumbil were infected with microsporidian parasites. The infection was recorded as tumor-like masses (whitish macroscopic cysts) or xenomas often up to 2 cm in diameter and embedded in the peritoneal cavity. Generally, the infection was increased during winter 63.8% (86 out of 135) and fall to 18.9% (17 out of 90) in summer. Light microscopic study revealed that xenomas were encapsulated by a fibrous layer encircling numerous sporophorous vesicles filled with mature spores measuring 1.7 ± 0.6 (1.5–2.7 μm) × 1.5 ± 0.3 μm (1.2–1.8 μm) in size. Ultrastructural microscopic study showed the presence of smooth membranes of the sarcoplasmic reticulum forming a thick, amorphous coat surrounding various developmental stages of the parasite. The various recognizable stages of the parasite were uninuclear, binucleated, and multinucleated meronts followed by detachment of the plasmalemma of the sporont from the sporophorous vesicle producing sporoblasts. Mature spores consist of a spore coat and spore contents. The spore contents consist of the uninucleated sporoplasm and a posterior vacuole located at the posterior end. The polar tube consists of a straight shaft and a coiled region (26–32 coils) arranged in many rows along the inside periphery of the spore. The polaroplast consisted of an anterior region of closely and loosely packed membranes. Molecular analysis based on the small subunit rDNA gene was performed to determine the phylogenetic position of the present species. The percentage identity between this species and a range of other microsporidia predominantly from aquatic hosts demonstrated a high degree of similarity (>92%) with eight Pleistophora species. Comparison of the nucleotide sequences and divergence showed that the sequence of the present microsporidium was most similar to that of Pleistophora anguillarum (99.8% identity) differing in 13 nucleotide positions. So, the present species was recorded and phylogenetically positioned as a new species of Pleistophora .
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Ultrastructure, development, and host–parasite relationship of a new species of the genus Pleistophora—a microsporidian parasite of the marine fish Epinephelus chlorostignei
Parasitology Research, 2009Co-Authors: F. Abdel Ghaffar, A.-r. Bashtar, Heinz Mehlhorn, Khaled Al-rasheid, Ebtsam Al-olayan, Eglal Koura, Kareem MorsyAbstract: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 .
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Ultrastructure, development, and host-parasite relationship of a new species of the genus Pleistophora--a microsporidian parasite of the marine fish Epinephelus chlorostignei.
Parasitology research, 2009Co-Authors: F. Abdel Ghaffar, A.-r. Bashtar, Heinz Mehlhorn, Khaled Al-rasheid, Ebtsam Al-olayan, Eglal Koura, Kareem MorsyAbstract: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.
Ann Cali - One of the best experts on this subject based on the ideXlab platform.
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A review of the development of two types of human skeletal muscle infections from microsporidia associated with pathology in invertebrates and cold-blooded vertebrates.
Folia parasitologica, 2005Co-Authors: Ann Cali, Louis M. Weiss, Peter M. TakvorianAbstract:Traditionally, the Microsporidia were primarily studied in insects and fish. There were only a few human cases of microsporidiosis reported until the advent of AIDS, when the number of human microsporidian infections dramatically increased and the importance of these new pathogens to medicine became evident. Over a dozen different kinds of microsporidia infecting humans have been reported. While some of these infections were identified in new genera (Enterocytozoon, Vittaforma), there were also infections identified from established genera such as Pleistophora and Encephalitozoon. The genus Pleistophora, originally erected for a species described from fish muscle, and the genus Encephalitozoon, originally described from disseminated infection in rabbits, suggested a link between human infections and animals. In the 1980's, three Pleistophora sp. infections were described from human skeletal muscle without life cycles presented. Subsequently, the genus TrachiPleistophora was established for a human-infecting microsporidium with developmental differences from species of the genus Pleistophora. Thus, the existence of a true Pleistophora sp. or spp. in humans was put into question. We have demonstrated the life-cycle stages of the original Pleistophora sp. (Ledford et al. 1985) infection from human muscle, confirming the existence of a true Pleistophora species in humans, P. ronneafiei Cali et Takvorian, 2003, the first demonstrated in a mammalian host. Another human infection, caused by a parasite from invertebrates, was Brachiola algerae (Vavra et Undeen, 1970) Lowman, Takvorian et Cali, 2000. The developmental stages of this human muscle-infecting microsporidium demonstrate morphologically what we have also confirmed by molecular means, that B. algerae, the mosquito parasite, is the causative agent of this human skeletal muscle infection. B. algerae had previously been demonstrated in humans but only in surface infections, skin and eye. The diagnostic features of B. algerae and P. ronneafiei infections in human skeletal muscle are presented. While Encephalitozoon cuniculi has been known as both an animal (mammal) and human parasite, the idea of human microsporidial infections derived from cold-blooded vertebrates and invertebrates has only been suggested by microsporidian phylogeny based on small subunit ribosomal DNA sequences but has not been appreciated. The morphological data presented here demonstrate these relationships. Additionally, water, as a link that connects microsporidial spores in the environment to potential host organisms, is diagrammatically presented.
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Kyphosis Associated with Microsporidial Myositis in San Marcos Salamanders, Eurycea nana
Journal of Herpetological Medicine and Surgery, 2005Co-Authors: Kathryn C. Gamble, Ann Cali, Michael M. Garner, Gary West, Elizabeth S. Didier, Thomas P. AlvaradoAbstract:ABSTRACT Captive refugia for four species of plethodontid salamanders were established. Following this successful maintenance, two of the species presented with kyphosis. In one of these species (San Marcos salamander, Eurycea nana), microsporidial organisms within the epaxial musculature were identified in post-mortem histopathology and confirmed by polymerase chain reaction rDNA sequence as most closely similar to Encephalitozoon helium. However, ultrastructural analysis and further rDNA sequencing suggested a new species of Pleistophora. In these affected individuals, the microsporidial infection produced kyphosis resulting from inflammation and fibrosis of the epaxial musculature to the parasite.
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Ultrastructure and Development of Pleistophora ronneafiei n. sp., a Microsporidium (Protista) in the Skeletal Muscle of an Immune-Compromised Individual
The Journal of eukaryotic microbiology, 2003Co-Authors: Ann Cali, Peter M. TakvorianAbstract:This report provides a detailed ultrastructural study of the life cycle, including proliferative and sporogonic developmental stages, of the first Pleistophora species (microsporidium) obtained from an immune-incompetent patient. In 1985, the organism obtained from a muscle biopsy was initially identified as belonging to the genus Pleistophora, based on spore morphology and its location in a sporophorous vesicle. Since that initial report, at least two new microsporidial genera, TrachiPleistophora and Brachiola, have been reported to infect the muscle tissue of immunologically compromised patients. Because TrachiPleistophora development is similar to Pleistophora, and as Pleistophora was only known to occur in cold-blooded hosts, the question of the proper classification of this microsporidium arose. The information acquired in this study makes it possible to compare Pleistophora sp. (Ledford et al. 1985) to the known human infections and properly determine its correct taxonomic position. Our ultrastructural data have revealed the formation of multinucleate sporogonial plasmodia, a developmental characteristic of the genus Pleistophora and not TrachiPleistophora. A comparison with other species of the genus supports the establishment of a new species. This parasite is given the name Pleistophora ronneafiei n. sp.
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ultrastructural study of the development of Pleistophora schubergi zwolfer 1927 protozoa microsporida in larvae of the spruce budworm choristoneura fumiferana and its subsequent taxonomic change to the genus endoreticulatus
Journal of Eukaryotic Microbiology, 1991Co-Authors: Ann Cali, Manal El GarhyAbstract:This study demonstrates that Pleistophora schubergi Zwolfer, 1927, a microsporidium originally isolated from the midgut epithelium of Nygmia phaeorrhoea Don (Euproctis chrysorrhoea L.) and Porthetria dispar L., and subsequently reported in several other insects including the spruce budworm, Choristoneura fumiferana (the host used in this investigation), does not belong in the genus Pleistophora Gurley, 1893. Pleistophora schubergi lacks the major features that are characteristic of Pleistophora typicalis, the type species of this genus. A comparison of ultrastructural observations reported for the type species of the genus Pleistophora, P. typicalis, and our observations of P. schubergi revealed significant differences. A thick (0.5 μm) amorphous coat, derived from parasite secretions and deposited external to the parasite plasmalemma, surrounds all developmental stages in P. typicalis. Double membranes, derived from host rough endoplasmic reticulum cisternae encircle the parasite plasmalemma of all developmental stages in P. schubergi. The sporophorous vesicle encases the spores in P. typicalis, and originates from the parasite-secreted coat that is present around meronts. In P. schubergi, the host endoplasmic reticulum cisternae form the envelope that surrounds the meronts. Moreover, the sporophorous vesicle envelope in P. typicalis persists around groups of spores, while in P. schubergi this envelope breaks easily to release the spores in the host cytoplasm. By comparing the characteristics of the microsporidium found in the spruce budworm with those of the recently created polysporous genera that sporulate within a vesicle, we found that P. schubergi does belong in the new genus Endoreticulatus Brooks et al. 1988, and consequently rename it Endoreticulatus schubergi (Zwolfer, 1927) n. comb.
F. Abdel Ghaffar - One of the best experts on this subject based on the ideXlab platform.
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Ultrastructure and molecular phylogenetics of a new isolate of Pleistophora pagri sp. nov. (Microsporidia, Pleistophoridae) from Pagrus pagrus in Egypt.
Parasitology Research, 2012Co-Authors: Kareem Morsy, A.-r. Bashtar, F. Abdel Ghaffar, Heinz Mehlhorn, Rewaida Abdel-gaberAbstract:The spore morphology and molecular systematic of a new microsporidian which was isolated from the common sea bream Pagrus pagrus (F: Sparidae Linnaeus, 1758) from the Red Sea, Egypt have been studied. Fifty-six out of 300 (18.7 %) of this fish were infected with microsporidian parasites. The infection was appeared as whitish, ellipsoid, round, or elongated nodules embedded in the epithelial lining of the peritoneum and also in the intestinal epithelium. Light microscopic study revealed that nodules were encapsulated by a fibrous layer encircling numerous mature spores measuring 1.7 ± 0.6 (1.5–2.7 μm) × 1.5 ± 0.3 μm (1.2–1.8 μm) in size. Ultrastructure of spores was characteristic for the genus Pleistophora: dimorphic, uninucleate spores (each spore possesses three to five polar filament coils) and a posterior vacuole. Also, the early recognizable stages of the parasite within nodules include uninucleated, binucleated, and multinucleated meronts followed by detachment of the plasmalemma of the sporont producing sporoblasts which mature to spores that consist of a spore coat and spore contents. Also, we analyzed the small subunit ribosomal gene (SSUrDNA) using PCR and sequencing specimens from the marine populations of P. pagrus fish from the Red Sea. From blast searches, sequence analysis, and phylogenetic analysis, we did not find corresponding GenBank entries to our species. Comparison of the nucleotide sequences showed that the sequence of our microsporidium was most similar to five Pleistophora species with degrees of identity (>91.5 %). It was most similar (97.8 % identity) to that of Pleistophora hyphessobryconis (account no. GU126672) differing in 19 nucleotide positions and with lower divergence value, Pleistophora ovariae (96.2 % identity, account no. AJ252955), Pleistophora hippoglossoideos (91.9 % identity, account no. AJ252953), Pleistophora mulleri (91.9 % identity, account no. EF119339), and Pleistophora typicalis (91.9 % identity, account no. AJ252956). So, they likely represent new species named Pleistophora pagri sp. n. with accession number JF797622 and a GC content of 53 %.
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Morphological and molecular biological characterization of Pleistophora aegyptiaca sp. nov. infecting the Red Sea fish Saurida tumbil
Parasitology Research, 2012Co-Authors: F. Abdel Ghaffar, A.-r. Bashtar, Heinz Mehlhorn, Kareem Morsy, Saleh Al-quraishy, Khaled Al-rasheid, Rewaida Abdel-gaberAbstract:One hundred three out of 225 (45.8%) of the Red Sea fish Saurida tumbil were infected with microsporidian parasites. The infection was recorded as tumor-like masses (whitish macroscopic cysts) or xenomas often up to 2 cm in diameter and embedded in the peritoneal cavity. Generally, the infection was increased during winter 63.8% (86 out of 135) and fall to 18.9% (17 out of 90) in summer. Light microscopic study revealed that xenomas were encapsulated by a fibrous layer encircling numerous sporophorous vesicles filled with mature spores measuring 1.7 ± 0.6 (1.5–2.7 μm) × 1.5 ± 0.3 μm (1.2–1.8 μm) in size. Ultrastructural microscopic study showed the presence of smooth membranes of the sarcoplasmic reticulum forming a thick, amorphous coat surrounding various developmental stages of the parasite. The various recognizable stages of the parasite were uninuclear, binucleated, and multinucleated meronts followed by detachment of the plasmalemma of the sporont from the sporophorous vesicle producing sporoblasts. Mature spores consist of a spore coat and spore contents. The spore contents consist of the uninucleated sporoplasm and a posterior vacuole located at the posterior end. The polar tube consists of a straight shaft and a coiled region (26–32 coils) arranged in many rows along the inside periphery of the spore. The polaroplast consisted of an anterior region of closely and loosely packed membranes. Molecular analysis based on the small subunit rDNA gene was performed to determine the phylogenetic position of the present species. The percentage identity between this species and a range of other microsporidia predominantly from aquatic hosts demonstrated a high degree of similarity (>92%) with eight Pleistophora species. Comparison of the nucleotide sequences and divergence showed that the sequence of the present microsporidium was most similar to that of Pleistophora anguillarum (99.8% identity) differing in 13 nucleotide positions. So, the present species was recorded and phylogenetically positioned as a new species of Pleistophora .
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Ultrastructure, development, and host–parasite relationship of a new species of the genus Pleistophora—a microsporidian parasite of the marine fish Epinephelus chlorostignei
Parasitology Research, 2009Co-Authors: F. Abdel Ghaffar, A.-r. Bashtar, Heinz Mehlhorn, Khaled Al-rasheid, Ebtsam Al-olayan, Eglal Koura, Kareem MorsyAbstract: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 .
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Ultrastructure, development, and host-parasite relationship of a new species of the genus Pleistophora--a microsporidian parasite of the marine fish Epinephelus chlorostignei.
Parasitology research, 2009Co-Authors: F. Abdel Ghaffar, A.-r. Bashtar, Heinz Mehlhorn, Khaled Al-rasheid, Ebtsam Al-olayan, Eglal Koura, Kareem MorsyAbstract: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.