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Sample records for apicomplexa

  1. Does protein phosphorylation govern host cell entry and egress by the Apicomplexa?

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    Jacot, Damien; Soldati-Favre, Dominique

    2012-01-01

    Members of the phylum Apicomplexa are responsible for a wide range of diseases in humans and animals. The absence of an effective vaccine or safe curing drugs and the continuous emergence of resistant parasites to available treatments impose a high demand on the identification of novel targets for intervention against the apicomplexans. Protein kinases are considered attractive potential therapeutic targets not only against cancers but also to combat infectious diseases. The scope and aim of ...

  2. Comparative genomic analysis of multi-subunit tethering complexes demonstrates an ancient pan-eukaryotic complement and sculpting in Apicomplexa.

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    Christen M Klinger

    Full Text Available Apicomplexa are obligate intracellular parasites that cause tremendous disease burden world-wide. They utilize a set of specialized secretory organelles in their invasive process that require delivery of components for their biogenesis and function, yet the precise mechanisms underpinning such processes remain unclear. One set of potentially important components is the multi-subunit tethering complexes (MTCs, factors increasingly implicated in all aspects of vesicle-target interactions. Prompted by the results of previous studies indicating a loss of membrane trafficking factors in Apicomplexa, we undertook a bioinformatic analysis of MTC conservation. Building on knowledge of the ancient presence of most MTC proteins, we demonstrate the near complete retention of MTCs in the newly available genomes for Guillardiatheta and Bigelowiellanatans. The latter is a key taxonomic sampling point as a basal sister taxa to the group including Apicomplexa. We also demonstrate an ancient origin of the CORVET complex subunits Vps8 and Vps3, as well as the TRAPPII subunit Tca17. Having established that the lineage leading to Apicomplexa did at one point possess the complete eukaryotic complement of MTC components, we undertook a deeper taxonomic investigation in twelve apicomplexan genomes. We observed excellent conservation of the VpsC core of the HOPS and CORVET complexes, as well as the core TRAPP subunits, but sparse conservation of TRAPPII, COG, Dsl1, and HOPS/CORVET-specific subunits. However, those subunits that we did identify appear to be expressed with similar patterns to the fully conserved MTC proteins, suggesting that they may function as minimal complexes or with analogous partners. Strikingly, we failed to identify any subunits of the exocyst complex in all twelve apicomplexan genomes, as well as the dinoflagellate Perkinsus marinus. Overall, we demonstrate reduction of MTCs in Apicomplexa and their ancestors, consistent with modification during

  3. Occurrence of Cryptosporidium (Apicomplexa, Cryptosporidiidae in Crotalus durissus terrificus (Serpentes, Viperidae in Brazil

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    Karasawa Andréa Satie Matsubara

    2002-01-01

    Full Text Available The objective of the present study was to investigate the prevalence of Cryptosporidium (Apicomplexa, Cryptosporidiidae in the snake Crotalus durissus terrificus (Serpentes, Viperidae. Fifty animals were evaluated for the presence of oocysts of Cryptosporidium sp. at the time of arrival and 30 and 60 days later. Intestinal washings with saline solution (1% body weight, fecal samples, and organ scrapings were collected during the study. Oocysts were concentrated by an ether-phosphate-buffered saline sedimentation technique and then separated by a density gradient centrifugation technique. Smears were made with the sediment and submitted to modified acid-fast and auramine-rhodamine staining. Cryptosporidium-positive smears were used as controls for the experimental findings. The overall prevalence of Cryptosporidium sp. oocysts was 14%. Among the positive snakes, oocysts were detected only in the intestinal washing in two specimens, only in the feces in four specimens, and in both materials at least once in one specimen. The positive snakes were predominantly from Santa Maria da Serra city State of São Paulo (57.1%. We also observed that all of the examinations that presented positive results were obtained at least 27 days after the capture of the animals.

  4. The red-tailed hawk, Buteo jamaicensis, a native definitive host of Frenkelia microti (Apicomplexa) in North America.

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    Upton, S J; McKown, R D

    1992-01-01

    Oral inoculation of prairie voles, Microtus ochrogaster, with coccidian sporocysts isolated from the feces of a red-tailed hawk, Buteo jamaicensis, in Kansas, USA, resulted in formation of Frenkelia microti (Apicomplexa: Sarcocystidae) tissue cysts in the brains of the voles. Five additional isolates of morphologically similar sporocysts collected from red-tailed hawks or other Buteo spp. in Kansas failed to result in detectable infections in rodents. These results are the first to verify that red-tailed hawks are natural definitive host in North America for F. microti.

  5. Eimeria pileata n. sp. (Apicomplexa: Eimeriidae) from the rufous-capped brush finch Atlapetes pileatus Wagler (Passeriformes: Emberizidae) in Mexico.

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    Soriano-Vargas, Edgardo; Medina, Juan Pablo; Salgado-Miranda, Celene; García-Conejo, Michele; Galindo-Sánchez, Karla Patrícia; Janczur, Mariusz Krzysztof; Berto, Bruno Pereira; Lopes, Carlos Wilson Gomes

    2015-11-01

    A new coccidian species (Protista: Apicomplexa: Eimeriidae) collected from the rufous-capped brush finch Atlapetes pileatus Wagler in the Nevado de Toluca Natural Protected Area, Mexico. Oöcysts of Eimeria pileata n. sp. are ellipsoidal, measuring on average 16.5 × 14.1 μm, with a smooth, bi-layered wall. Micropyle and oöcyst residuum are absent, but a polar granule is present. Sporocysts are ellipsoidal, measuring on average 9.0 × 5.4 μm. Stieda and sub-Stieda bodies are both present. A sporocyst residuum is present as a compact mass of granules. This is the third description of an eimeriid coccidian infecting passerines.

  6. Isospora celata n. sp. (Apicomplexa: Eimeriidae) from the orange-crowned warbler Oreothlypis celata (Say) (Passeriformes: Parulidae) in Mexico.

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    Berto, Bruno Pereira; Medina, Juan Pablo; Salgado-Miranda, Celene; García-Conejo, Michele; Janczur, Mariusz Krzysztof; Lopes, Carlos Wilson Gomes; Soriano-Vargas, Edgardo

    2014-11-01

    A new coccidian species (Protista: Apicomplexa: Eimeriidae) is described from the orange-crowned warbler Oreothlypis celata (Say) collected in the Nevado de Toluca National Park, Mexico at 3,000 metres above sea level. Isospora celata n. sp. has subspheroidal oöcysts, measuring 28.4 × 26.4 μm, with smooth, bi-layered wall c.1.2 μm thick. Micropyle and polar granule are absent, but oöcyst residuum is present as a compact mass. Sporocysts are ovoidal, 18.2 × 12.8 µm. Stieda body knob-like and sub-Stieda body irregular and barely discernible. Sporocyst residuum is composed of granules of different sizes. Sporozoites are vermiform with one refractile body and a nucleus. This is the third description of an isosporoid coccidian infecting a New World warbler.

  7. Isospora cardellinae n. sp. (Apicomplexa: Eimeriidae) from the red warbler Cardellina rubra (Swainson) (Passeriformes: Parulidae) in Mexico.

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    Salgado-Miranda, Celene; Medina, Juan Pablo; Zepeda-Velázquez, Andrea Paloma; García-Conejo, Michele; Galindo-Sánchez, Karla Patricia; Janczur, Mariusz Krzysztof; Soriano-Vargas, Edgardo

    2016-10-01

    A new coccidian species (Protozoa: Apicomplexa: Eimeriidae) collected from the red warbler Cardellina rubra (Swainson) is reported from the Nevado de Toluca National Park, Mexico. Isospora cardellinae n. sp. has subspherical oöcysts, measuring on average 26.6 × 25.4 μm, with smooth, bi-layered wall, c.1.3 μm thick. Micropyle, oöcyst residuum, and polar granule are absent. Sporocysts are ovoidal, measuring on average 19.0 × 12.0 µm, with a knob-like Stieda body, a trapezoidal sub-Stieda body and sporocyst residuum composed of scattered spherules of different sizes. Sporozoites are vermiform with one refractile body and a nucleus. This is the fourth description of an isosporoid coccidian infecting a New World warbler.

  8. A new coccidian, Isospora rheae sp. nov. (Apicomplexa, Eimeriidae, from Rhea americana (Aves, Rheidae from South America

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    Samira S.M. Gallo

    2014-12-01

    Full Text Available A new species of coccidian (Protozoa: Apicomplexa: Eimeriidae obtained from rheas, Rhea americana, is reported in Brazil. Oocysts of Isospora rheae sp. nov. are spherical to subspheroidal, measuring 22.6 × 21.0 µm, and have a double and smooth wall that is approximately 1.7 µm thick. The micropyle, oocyst residuum and polar granule are absent. Sporocysts are slightly ovoid, measuring 13.9 × 9.6 µm. The Stieda body is flattened, the substieda body is pointed, irregular and wavy and the sporocyst residuum is composed of scattered granules of varying sizes. Sporozoites have an oblong refractile body and one nucleus. This is the first description of an isosporid coccidian infecting birds of the family Rheidae.

  9. Multi-membrane-bound structures of Apicomplexa: II. the ovoid mitochondrial cytoplasmic (OMC) complex of Toxoplasma gondii tachyzoites.

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    Köhler, Sabine

    2006-03-01

    Apicomplexa including the causative agents of toxoplasmosis and malaria reportedly possess one or few tubular-shaped mitochondria that permeate, more or less branched, throughout these unicellular parasites. Electron micrographs generated herein from serial-sectioned Toxoplasma gondii tachyzoites demonstrated, however, a greater diversity regarding both the shape of the cultured parasite's single mitochondrion and its sub-structural organization. Moreover, a unique subcellular construction was detected that basically comprised a pouch-shaped subdivision of the tachyzoite mitochondrion plus a fraction of parasitic cytoplasm enclosed therein. This composite assembling, termed ovoid mitochondrial cytoplasmic (OMC) complex, characteristically displayed a highly reduced matrix lumen of its mitochondrial border construction, which furthermore often failed to possess any cristae or contained tightly pleated cristae, thus creating a pouch-shaped multi-laminar wall of four or more membranous layers, respectively. Given this architecture, cross-sectioned OMC complexes of T. gondii tachyzoites frequently mimicked in size and shape the parasites' plastid-like organelle (apicoplast). Moreover, like the apicoplast, the OMC complex was often found adjacent to the tachyzoite's single Golgi complex and constantly located in close proximity to the outer membrane of the parasite's nuclear envelope. The T. gondii OMC complex differed, however, from the apicoplast in its exact fine structural organization and a stage-restricted presence that was apparently linked to mitochondrial growth and/or division. Any special function(s) possibly performed by the T. gondii OMC complex remains, nevertheless, to be elucidated.

  10. A new Apicomplexa-specific protein kinase family : multiple members in Plasmodium falciparum, all with an export signature

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    Mercereau-Puijalon Odile

    2005-03-01

    Full Text Available Abstract Background Malaria caused by protozoan parasites of the genus Plasmodium spp. is a major health burden in tropical countries. The development of new control tools, including vaccines and drugs, is urgently needed. The availability of genome sequences from several malaria parasite species provides a basis on which to identify new potential intervention targets. Database mining for orthologs to the Plasmodium falciparum trophozoite protein R45, a vaccine candidate, led us identify a new gene family. Results Orthologs to the P. falciparum trophozoite protein R45 were detected exclusively in protozoan parasites of the phylum Apicomplexa, including several Plasmodium spp., Toxoplasma gondii and Cryptosporidium parvum. All family members are hybrid genes with a conserved C-terminal protein kinase domain of a novel type, recently called FIKK kinase, associated with a non conserved N-terminal region without any known functional signature. While a single copy gene was detected in most species, considerable gene expansion was observed in P. falciparum and its closest phylogenic relative P. reichenowi, with 20 and six copies, respectively, each with a distinct N-terminal domain. Based on full length protein sequence, pairs of orthologs were observed in closely related species, such as P. berghei and P.y. yoelii, P. vivax and P. knowlesi, or P. reichenowi and P. falciparum. All 20 P. falciparum paralogs possess a canonical Plasmodium export element downstream of a signal / anchor sequence required for exportation outside the parasitophorous vacuole. This is consistent with the reported association of the trophozoite protein R45, the only paralog characterised to date, with the infected red blood cell membrane. Interestingly, most genes are located in the subtelomeric region of chromosomes, in association with other multigene families contributing to the remodelling of the infected red blood cell membrane, in particular the ring erythrocyte surface

  11. Aggregata (Protozoa: Apicomplexa) infection in the common octopus Octopus vulgaris from the West Mediterranean Sea: The infection rates and possible effect of faunistic, environmental and ecological factors

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    Mayo-Hernández, E.; Barcala, E.; Berriatua, E.; García-Ayala, A.; Muñoz, P.

    2013-10-01

    Prevalence and distribution of the coccidian parasite Aggregata octopiana (Protozoa: Apicomplexa) in common octopus (Octopus vulgaris) in the Mediterranean Spanish coasts were studied. A total of 114 octopuses were sampled from 30 geographic sectors by trawl fleet, and whitish macroscopic oocysts typical of A. octopiana infection were recorded in 96% of octopuses in the digestive tract and mainly in intestine and spiral caecum. The univariate analysis showed that lesion extension varied according to specific octopus, environmental and faunistic variables. A subsequent multivariable analysis indicated that the risk of macroscopic lesions in the caecum was greater in males compared to females, in octopuses living in deeper compared to shallower waters and in hauls where the crustacean Pagurus excavatus was present. The study provides further evidence of the abundance of A. octopiana in octopus ecosystems urging for further studies to evaluate its health impact. The combined abundance of infected octopuses and P. excavatus merits attention.

  12. Coccidia of New World psittaciform birds (Aves: Psittaciformes): Eimeria ararae n. sp. (Apicomplexa: Eimeriidae) from the blue-and-yellow macaw Ara ararauna (Linnaeus).

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    do Bomfim Lopes, Bruno; Berto, Bruno Pereira; de Carvalho Balthazar, Lianna Maria; Coelho, Cleide Domingues; Neves, Daniel Medeiros; Lopes, Carlos Wilson Gomes

    2014-06-01

    In the New World, the avian order Psittaciformes comprises 142 species, yet to date only 3 (2%) of the species have been examined for coccidia, and from these only four species of Eimeria Schneider, 1875 have been described. In this study, a new coccidian species (Protozoa: Apicomplexa: Eimeriidae) obtained from the blue-and-yellow macaw Ara ararauna (Linnaeus) is reported from Brazil. Oöcysts of Eimeria ararae n. sp. are ovoidal, measure 28.7 × 20.2 μm and have a smooth, bi-layered wall c.1.1 μm thick. Both micropyle and oöcyst residuum are absent, but polar granules are present. Sporocysts are ovoidal and measure 17.0 × 8.3 µm, with knob-like, prominent Stieda body and sporocyst residuum is composed of granules; sub-Stieda body is absent. Sporozoites are vermiform with one refractile body and a nucleus. This is the fifth description of an eimerid coccidian infecting a New World psittaciform bird.

  13. Morpho-functional characterization and esterase patterns of the midgut of Tribolium castaneum Herbst, 1797 (Coleoptera: Tenebrionidae) parasitized by Gregarina cuneata (Apicomplexa: Eugregarinidae).

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    Gigliolli, Adriana A Sinópolis; Lapenta, Ana Silva; Ruvolo-Takasusuki, Maria Claudia Colla; Abrahão, Josielle; Conte, Hélio

    2015-09-01

    Tribolium castaneum (Coleoptera: Tenebrionidae) is a common pest of stored grains and byproducts and is normally infected by Gregarina cuneata (Apicomplexa: Eugregarinidae). The life cycle of this parasite includes the sporozoite, trophozoite, gamont, gametocyte, and oocyst stages, which occur between the epithelium and lumen of the host's midgut. This study aims to describe the morphofunctional alterations in the midgut and determine the esterase patterns in T. castaneum when parasitized by gregarines. To achieve this purpose, midguts of adult insects were isolated, processed, and analysed using light and electron microscopy. We determined total protein content, amylase activity, and the expression and related activities of the esterases by using polyacrylamide gel electrophoresis (PAGE). The midgut of T. castaneum is formed by digestive, regenerative, and endocrine cells. The effects of parasitism on the digestive cells are severe, because the gregarines remain attached to these cells to absorb all the nutrients they need throughout their development. In these cells, the most common alterations observed include expansion and fragmentation of the rough endoplasmic reticulum, development of the smooth endoplasmic reticulum, changes in mitochondrial cristae, cytoplasmic vacuolization, formation of myelin structures, spherites, large intercellular spaces, autophagic vesicles, expansion of the basal labyrinth, and cytoplasmic protrusions. Deposits of glycogen granules were also observed. Amylase activity was reduced in parasitized insects. Regenerative cells were found in disorganized crypts and did not differentiate into new cells, thus, compromising the restoration of the damaged epithelium. Though few morphological alterations were observed in the endocrine cells, results suggest that the synthesis and/or release of hormones might be impaired. Nine esterases (EST-1 to 9) were identified in the midgut of T. castaneum and were expressed in varying levels in response

  14. Four new coccidia (Apicomplexa: Eimeriidae) from the Plateau zokor, Myospalax baileyi Thomas (Rodentia: Myospalacinae), a subterranean rodent from Haibei area, Qinghai Province, China.

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    Cao, Yi-Fan; Nie, Xu-Heng; Zhang, Tong-Zuo; Du, Shou-Yang; Duszynski, Donald W; Bian, Jiang-Hui

    2014-02-01

    Thirty-eight faecal samples from the Plateau zokor, Myospalax baileyi Thomas, collected in the Haibei Area, Qinghai Province, China, were examined for the presence of coccidia (Apicomplexa: Eimeriidae). Seventeen of 38 faecal samples (44.7%) were found to contain coccidian oöcysts representing four new species of Eimeria Schneider, 1875, and four of 17 (23.5%) infected zokors were concurrently infected with two or three of these eimerian species. The sporulated oöcysts of Eimeria myospalacensis n. sp. are ovoidal, 9.5-17.0 × 8.0-13.0 (mean 13.0 × 10.4) μm; a polar granule is present, oöcyst residuum is absent; sporocysts are ovoidal, 4.5-7.5 × 3.0-5.0 (mean 6.3 × 4.2) μm and have both a Stieda body and residuum. Oöcysts of Eimeria fani n. sp. are ellipsoidal to cylindroidal, 12.5-16.0 × 8.0-11.0 (mean 14.6 × 9.9) μm; a polar granule is present, but micropyle and residuum are lacking; sporocysts are ovoidal, 4.5-7.5 × 3.0-5.3 (mean 6.7 × 4.4) μm; a residuum and a Steida body are present. Oöcysts of Eimeria baileyii n. sp. are ellipsoidal, 15.0-23.0 × 12.0-18.0 (mean 18.2 × 13.7) μm; a polar granule is present but oöcyst residuum is absent; sporocysts are ovoidal, 8.0-11.0 × 5.0-7.0 (mean 9.5 × 5.9) μm and have both a Stieda body and residuum. Oöcysts of Eimeria menyuanensis n. sp. are ovoidal, 12.5-21.0 × 11.0-18.0 (mean 17.1 × 14.6) μm, with a distinct micropyle c.2.5 μm wide; a polar granule is present but a residuum is absent; sporocysts are ovoidal, 8.0-12.0 × 5.0-7.0 (mean 10.2 × 6.4) μm, and have both a Stieda body and residuum.

  15. Utilización del patrón de restricción del DNA codificante para el RNA Ribosomal de la subunidad pequeña para la caracterización de Apicomplexa

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    López Adelaida

    1996-12-01

    Full Text Available Los Apicomplexos constituyen un phylum de protozoarios que se caracterizan por ser parásitos obligados de una gran variedad de huéspedes vertebrados e invertebrados. Hoy en día hay fuertes polémicas en tomo a su clasificación taxonómica, sus relaciones filogenéticas, y los patrones de coevolución con sus hospederos. El gen que codifica para el ARN ribosomal de la subunidad pequeña (ARN-SURp se utiliza como marcador molecular para resolver estas inquietudes. A partir del ADN de las especies de la familia Sarcocystidae (Sarcocystis cruzi, Sarcocystis sp. de Didelphis marsupialis y Sarcocystis sp. de Columbina talpacoti y Toxoplasma gondii, y de especies de la familia Plasmodiidae (Plasmodium de Anolis chloris, P. simium, y P. falciparumi, se amplificó por PCR el gen que codifica para el ARN de la subunidad ribosomal pequeña (ARN- SURp usando los iniciadores P5-P3, 0009-2134 Y566R-567R. Se compararon
    los patrones de restricción Hind III, Eco RI, Sau 3AI y Alw 261 del DNA ribosomal. La prueba de riboprini mostró que además de discriminar entre familias permite caracterizar diferencias a nivel de género y especie.Apicomplexa is a Protozoa phylum in which all members are obliged parasites of a wide range of vertebrate and invertebrate hosts. There is an ongoing controversy on
    systematics, phylogenetic relationships and parasite - host coevolution patterns. The SSU ribosomal gen has been used as a molecular marker in order to solve these issues.
    From DNA of the species of the Sarcocystidae family (Sarcocystis cruzi, Sarcocystis sp. from Didelphis marsupialis, Sarcocystis sp. from Columbina talpacoti and Toxoplasma
    gondii, and from the species of the Plasmodiidae family (Plasmodium from Anolis ehloris, P. simium, and P. falciparum, the SSU ribosomal DNA fragemnt was
    amplified by PCR, using the pair of primers P5-P3, 0009-2134 and 566R-567R. Hind III, Eco RI, Sau 3AI and Alw 261 restriction pattems were compared

  16. Tomaculocystis corpulenta n. gen., n. sp. (Apicomplexa: Eugregarinorida) parasitizing the little yellow cockroach, Cariblatta lutea (Blattodea: Ectobiidae), in Alabama and Florida with recognition of Tomaculocystis cylindrosa n. comb. and Tomaculocystis mukundai n. comb. parasitizing ectobiid cockroaches in India.

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    Clopton, Richard E

    2015-02-01

    Tomaculocystis corpulenta n. gen., n. sp. (Apicomplexa: Eugregarinorida: Septatorina: Gregarinidae) is described from populations of the little yellow cockroach, Cariblatta lutea (Blattodea: Ectobiidae), established in laboratory culture from samples collected in Alabama and Florida. Tomaculocystis n. gen. are differentiated from other members of Gregarina by a markedly elliptoid gametocyst inside a persistent, lomentiform hyaline epicyst; developmental organization and growth of the spore tubes from gametocyst surface tumidi; and dehiscence by extrusion of non-chain forming oocysts through spore tubes that barely extend beyond the epicyst wall. Gregarina cylindrosa, Gregarina discocephala, and Gregarina mukundai are recognized as members of Tomaculocystis, and G. cylindrosa is recognized as the senior synonym of G. discocephala. Thus, Tomaculocystis cylindrosa n. comb. and Tomaculocystis mukundai n. comb. are formed. Species of Tomaculocystis are distinguished based on gamont deutomerite and oocyst shape and size. The oocysts of T. corpulenta are broadly dolioform, lack 4 polar knobs, and possess distinct, unique polar plates. Oocysts of all other known species in the genus are more oblong in shape, possess 4 polar knobs, and lack the distinct polar plates observed in the oocysts of T. corpulenta. Host utilization and geographic distribution among gregarine genera parasitizing the cockroach family Ectobiidae reveal a pattern of host-parasite specificity linking gregarine genera with ectobiidid subfamilies. Overall patterns suggest a hypothesis of European endemicy for Gamocystis, but hypotheses for the origin and radiation of Tomaculocystis or species of Gregarina infecting cockroaches are confounded by the cosmopolitan spread of pest cockroach species among humans.

  17. 顶复门原虫3-磷酸甘油醛脱氢酶功能及其应用研究进展%Research Advances on the Function and Applization of Glyceraldehydes-3-phosphate Dehydrogenase in Apicomplexa

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    廖申权; 戚南山; 吴彩艳; 吕敏娜; 袁建丰; 余劲术; 孙铭飞

    2012-01-01

    Glycolysis exists in various organisms. It is the major energetic process in apicomplexan parasites. Glyceralde-hyde-3-phosphate dehydrogenase (GAPDH) plays an important role in glycolysis,which closely related to the survival of parasites. GAPDH is proposed to be a potential target for antiparasitic drugs. This review will focus on glycolysis and the genetic analysis,mechanism and application of glyceraldehydes-3-phosphate dehydrogenase in Apicomplexa.%糖酵解途径广泛存在于各类生物中,是顶复门原虫的主要供能方式.3-磷酸甘油醛脱氢酶是糖酵解途径的重要酶,与顶复门原虫的生存密切相关,可以作为抗寄生虫药物研发的重要靶标.文章主要从顶复门原虫糖酵解途径、3-磷酸甘油醛脱氢酶的基因分析、作用机理及应用等方面进行综述.

  18. A new species of Caryospora Léger, 1904 (Apicomplexa: Eimeriidae) from the endangered Round Island boa Casarea dussumieri (Schlegel) (Serpentes: Bolyeridae) of Round Island, Mauritius: an endangered parasite?

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    Daszak, Peter; Ball, Stanley J; Streicker, Daniel G; Jones, Carl G; Snow, Keith R

    2011-02-01

    A new species of Caryospora Léger, 1904 (Apicomplexa: Eimeriidae), C. durelli n. sp., is described from the endangered Round Island boa Casarea dussumieri (Schlegel) (Serpentes: Bolyeridae) from Round Island, Mauritius. Six of 11 hosts were infected. Oöcysts are spherical to subspherical, 19.2 × 18.2 (17.5-21 × 16-21) μm, n = 20, and have a shape index (mean length/mean width) of 1.05 (1.02-1.09). The bi-layered wall is composed of an outer layer of c.0.6 μm thick and an inner layer of c.0.4 μm thick. A micropyle, oöcyst residuum and polar granule are absent. Sporocysts are ellipsoidal, 14.7 × 11.0 (13-16 × 9.5-11.5) μm, n = 20, and have a shape index of 1.33. Both Stieda and substieda bodies are present. The sporocyst residuum measures c.12 × 4.5 μm, is surrounded by sporozoites and composed of numerous granules. Refractile bodies are present but not clearly visible. This is the first coccidian parasite reported from the family Bolyeridae and the first species of Caryospora durrelli [corrected] reported from the Mascarenes. Conservation issues concerning parasites of endangered host species are discussed.

  19. Some remarks on the distribution and dispersion of Coccidia from icterid birds in South America: Isospora guaxi n. sp. and Isospora bellicosa Upton, Stamper & Whitaker, 1995 (Apicomplexa: Eimeriidae) from the red-rumped cacique Cacicus haemorrhous (L.) (Passeriformes: Icteridae) in southeastern Brazil.

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    da Silva, Lidiane Maria; Rodrigues, Mariana Borges; de Pinho, Irlane Faria; do Bomfim Lopes, Bruno; Luz, Hermes Ribeiro; Ferreira, Ildemar; Lopes, Carlos Wilson Gomes; Berto, Bruno Pereira

    2017-01-01

    A new species of coccidian, Isospora guaxi n. sp., and Isospora bellicosa Upton, Stamper & Whitaker, 1995 (Protozoa: Apicomplexa: Eimeriidae) are recorded from red-rumped caciques Cacicus haemorrhous (L.) in the Parque Nacional do Itatiaia, Brazil. Isospora guaxi n. sp. has sub-spheroidal oöcysts, measuring on average 30.9 × 29.0 μm, with smooth, bi-layered wall c.1.9 μm thick. Micropyle and oöcyst residuum are absent, but a polar granule is present. Sporocysts are ellipsoidal, measuring on average 19.3 × 13.8 μm. Stieda body is knob-like and sub-Stieda body is prominent and compartmentalized. Sporocyst residuum is composed of scattered granules. Sporozoites are vermiform, with one refractile body and a nucleus. Isospora bellicosa has sub-spheroidal to ovoidal oöcysts, measuring on average 27.1 × 25.0 μm, with smooth, bi-layered wall c.1.5 μm thick. Micropyle and oöcyst residuum are absent, but one or two polar granules are present. Sporocysts are ellipsoidal, measuring on average 18.1 × 10.9 μm. Stieda body is knob-like and sub-Stieda body is rounded to rectangular. Sporocyst residuum is composed of a cluster of compact or diffuse granules. Sporozoites are vermiform, with one refractile body and a nucleus. Isospora bellicosa was originally described from the Peruvian meadowlark Sturnella bellicosa deFilippi, a trans-Andean icterid which is allopatric with the cis-Andean C. haemorrhous. Therefore, in conclusion, this current study reveals the dispersion of coccidia from Icteridae across the Andes Mountains, besides describing the sixth isosporoid coccidium infecting an icterid bird.

  20. The complete mitochondrial genome sequence of Eimeria magna (Apicomplexa: Coccidia).

    Science.gov (United States)

    Tian, Si-Qin; Cui, Ping; Fang, Su-Fang; Liu, Guo-Hua; Wang, Chun-Ren; Zhu, Xing-Quan

    2015-01-01

    In the present study, we determined the complete mitochondrial DNA (mtDNA) sequence of Eimeria magna from rabbits for the first time, and compared its gene contents and genome organizations with that of seven Eimeria spp. from domestic chickens. The size of the complete mt genome sequence of E. magna is 6249 bp, which consists of 3 protein-coding genes (cytb, cox1 and cox3), 12 gene fragments for the large subunit (LSU) rRNA, and 7 gene fragments for the small subunit (SSU) rRNA, without transfer RNA genes, in accordance with that of Eimeria spp. from chickens. The putative direction of translation for three genes (cytb, cox1 and cox3) was the same as those of Eimeria species from domestic chickens. The content of A + T is 65.16% for E. magna mt genome (29.73% A, 35.43% T, 17.09 G and 17.75% C). The E. magna mt genome sequence provides novel mtDNA markers for studying the molecular epidemiology and population genetics of Eimeria spp. and has implications for the molecular diagnosis and control of rabbit coccidiosis.

  1. Observations on some Avian Coccidia (Apicomplexa: Eimeriidae in Amazonian Brazil

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    Ralph Lainson

    1994-09-01

    Full Text Available Oocysts of Eimeria porphyrulae n. sp. are described in faeces of Porphyrula martinica (Aves: Gruiformes: Rallidae. They are ellipsoidal to oval, 22.4 x 17.7 (20.0-23.7 x 16.2-18.7 µm, shape-index (length/width 1.3. Oocyst wall about 1.25 µm thick, colourless, with two layers: inner one prominently striated. Micropyle and sub-micropylar granule present: no oocyst residuum. Sporocysts 17.5 x 9.0 (17.0-19.0 x 8.0-10.0 µm, shape-index 1.9, with inconspicuous Stieda/sub-Stieda bodies. Sporocyst residuum of scattered granules, sometimes a compact mass: sporozoites with two refractile bodies. Eimeria crypturelli n. sp. is described in faeces of Crypturellus soiu (Tinamiformes: Tinamidae. Oocysts ellipsoidal-oval, 20.75 x 14.5 (17.5-25.0 x 11.25-21.25 µm, shape-index 1.4. Oocysts wall about 1.25 µm thick and bi-layered: inner layer faintly striated. Micropyle present, with oocyst residuum immediately below: single polar body rarely present. Sporocysts 13.0 x 7.5 (12.5-13.75 x 7,5-8.1 µm, shape-index 1.7, with a Stieda body but seemingly no sub-Stieda. Sporocyst residuum compact: sporozoites with two refractile bodies. Isospora cacici n. sp. is recorded from faeces of Cacicus cela cela (Passeriformes: Icteridae. Oocysts subspherical-spherical, 26.5 x 23.7 (22.5-27.5 x 20.0-26.2 µm, shape-index 1.1. Wall a single, colourless layer about 1.5 µm thick. No micropyle or oocyst residuum: 1-2 polar bodies. Sporocysts ellipsoidal, 17.7 x 12.5 (17.5-18.75 x 11.25-13.75 µm, shape-index 1.4, with pronounced Stieda/sub-Stieda bodies: residuum compact and sporozoites with two refractile bodies. Isospora thraupis n. sp. is described from faeces of Thraupis palmarum melanoptera (Passeriformes: Thraupidae. Oocysts subspherial-spherical, 19.9 x 19.0 (18.7-21.2 x 18.75-20.0 µm, shape-index 1.0. Wall about 0.6 µm thick, smooth, colourless and a single layer: no micropyle, oocyst residuum or polar bodies. Sporocysts 14.2 x 9.2 (13.7-16.2 x 8.7-10.0 µm, shape-index 1.5: Stied/sub-Stieda bodies inconspicuous. Residuum compact: sporozoites with two refractile bodies.

  2. Building the perfect parasite: cell division in apicomplexa.

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    Boris Striepen

    2007-06-01

    Full Text Available Apicomplexans are pathogens responsible for malaria, toxoplasmosis, and crytposporidiosis in humans, and a wide range of livestock diseases. These unicellular eukaryotes are stealthy invaders, sheltering from the immune response in the cells of their hosts, while at the same time tapping into these cells as source of nutrients. The complexity and beauty of the structures formed during their intracellular development have made apicomplexans the darling of electron microscopists. Dramatic technological progress over the last decade has transformed apicomplexans into respectable genetic model organisms. Extensive genomic resources are now available for many apicomplexan species. At the same time, parasite transfection has enabled researchers to test the function of specific genes through reverse and forward genetic approaches with increasing sophistication. Transfection also introduced the use of fluorescent reporters, opening the field to dynamic real time microscopic observation. Parasite cell biologists have used these tools to take a fresh look at a classic problem: how do apicomplexans build the perfect invasion machine, the zoite, and how is this process fine-tuned to fit the specific niche of each pathogen in this ancient and very diverse group? This work has unearthed a treasure trove of novel structures and mechanisms that are the focus of this review.

  3. Phylogeny of Fish-Infecting Calyptospora species (Apicomplexa: Eimeriorina)

    Science.gov (United States)

    There are numerous species of apicomplexans that infect poikilothermic vertebrates such as fishes, and possess unique morphological features that provide insight into the evolution of this important phylum of parasites. Here the relationship of the fish-infecting Calyptospora spe...

  4. Life cycle of Hammondia hammondi (Apicomplexa: Sarcocystidae) in cats

    Science.gov (United States)

    Hammondia hammondi and Toxoplasma gondii are feline coccidian that are morphologically, antigenically, and phylogenitically related. Both parasites multiply asexually and sexually in feline intestinal enterocytes but H. hammondi remains confined to enterocytes whereas T. gondii also parasitizes extr...

  5. Developmental biology of Cystoisospora (Apicomplexa: Sarcocystidae) monozoic tissue cysts

    Science.gov (United States)

    Tissue cyst stages are an intriguing aspect of the developmental cycle and transmission of members of the Family Sarcocystidae. Tissue cyst stages of the genera Toxoplasma, Hammondia, Neospora, Besnoitia, and Sarcocystis contain many infectious stages (bradyzoites).The tissue cyst stage of Cystoisos...

  6. Sarcocystis cruzi (Apicomplexa: Sarcocystidae no cachorro-do-mato (Cerdocyon thous Sarcocystis cruzi (Apicomplexa: Sarcocystidae in the crab-eating fox (Cerdocyon thous

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    Janaina S. Rodrigues

    2008-11-01

    Full Text Available Esporocistos de Sarcocystis foram identificados nas amostras fecais de um cachorro-do-mato. Eles foram dados por via oral para um bezerro em aleitamento, sendo observados cistos com morfologia compatível com os de Sarcocystis cruzi na musculatura cardíaca e esquelética, três meses após a infecção. Musculatura cardíaca deste bezerro foi dada para um segundo cão doméstico livre de coccídios, que eliminou esporocistos compatíveis com os de Sarcocystis em suas fezes, tendo com períodos pré-patente e patente 11 e 12 dias após a infecção respectivamente. Para comparar a morfologia dos esporocistos e cistos, um segundo cão, também livre de coccídios, foi alimentado com musculatura cardíaca de um bovino infectando naturalmente e positivo para cistos de S. cruzi. Esporocistos compatíveis com os eliminados pelo primeiro cão foram encontrados nas fezes. Apesar dos esporocistos eliminados pelo cachorro-do-mato serem significativamente diferentes dos eliminados pelos cães infectados experimentalmente, pode se considerar com base na morfologia dos esporocistos, cistos e na transmissão biológica que a espécie encontrada nas fezes do cachorro-do-mato é Sarcocystis cruzi.Sporocysts of Sarcocystis were identified in feces samples of a crab-eating fox, and were orally given to a suckling calf; after 3 months of infection, sarcocysts morphologically similar to Sarcocystis cruzi were observed in cardiac and skeletal striated muscles. The cardiac muscles of this calf were orally given to a puppy free of coccidia, that shed sporocysts in its feces.with a prepatent and patent period of 11 and 12 days after infection, respectively. To compare the morphology of the sporocysts and cysts, a second puppy was fed on bovine cardiac muscles infected naturally, and sporocysts identical to those shed by the first dog were recovered from its feces. In spite of the significant difference between sporocysts found in the mucosa of the crab-eating fox and those shed by the first and second puppies, the species observed in this study was considered to be Sarcocystis cruzi, based on size of the sporocyts, morphology of the cyst wall, and the pray-predator cycle.

  7. Hemosporid (Apicomplexa, Hematozoea, Hemosporida) community structure off pattern in wintering wild turkeys.

    Science.gov (United States)

    Fedynich, A M; Rhodes, O E

    1995-07-01

    The hemosporid community of 76 wild turkeys (Meleagris gallopavo silvestris) from South Carolina (USA) was examined using thin blood smears collected during January and February 1994. High prevalences and low abundances of hemosporids characterized this community. Leucocytozoon smithi and Haemoproteus meleagridis occurred in 100% and 54% of the turkeys, respectively; a Plasmodium sp. was found in one bird. Prevalence of H. meleagridis was significantly higher in juvenile turkeys than adults, but prevalences did not differ significantly among four trap sites or by host sex. Mean (+/- SE) intensities of L. smithi, H. meleagridis, and Plasmodium sp. were 3.4 +/- 0.4, 1.8 +/- 0.3, and 3.0 per 10,000 erythrocytes, respectively. Abundances of L. smithi, H. meleagridis, and Plasmodium sp. were 3.4 +/- 0.9 +/- 0.2, and < 0.1 +/- < 0.1 per 10,000 erythrocytes, respectively. Juvenile turkeys had higher rank abundance values of L. smithi than adults, whereas no differences were found among trap sites or between sexes. No differences in rank abundances of H. meleagridis were found among trap sites, host age, or host sex variables. Collectively, both common hemosporid species varied by host age, reflecting higher abundances in juvenile turkeys. patterns of hemosporid prevalence appeared similar to patterns found in subtropical regions. Based on our data, we recommend using prevalence and abundance data to analyze the structure and pattern of hemosporid communities at the component community level.

  8. Sarcocystis cruzi (Apicomplexa: Sarcocystidae) no cachorro-do-mato (Cerdocyon thous)

    OpenAIRE

    Janaina S. Rodrigues; Gisele S. Meireles; Paulo R. Carvalho Filho; Ribeiro, Carlos T.; Flausino,Walter; Lopes,Carlos Wilson G.

    2008-01-01

    Esporocistos de Sarcocystis foram identificados nas amostras fecais de um cachorro-do-mato. Eles foram dados por via oral para um bezerro em aleitamento, sendo observados cistos com morfologia compatível com os de Sarcocystis cruzi na musculatura cardíaca e esquelética, três meses após a infecção. Musculatura cardíaca deste bezerro foi dada para um segundo cão doméstico livre de coccídios, que eliminou esporocistos compatíveis com os de Sarcocystis em suas fezes, tendo com períodos pré-patent...

  9. Identification of sporozoite surface proteins and antigens of Eimeria nieschulzi (Apicomplexa)

    Energy Technology Data Exchange (ETDEWEB)

    Tilley, M.; Upton, S.J. (Kansas State Univ., Manhattan (USA))

    1990-03-01

    Sodium dodecyl sulfate polyacrylamide gel electrophoresis, immunoblotting, lectin binding, and {sup 125}I surface labeling of sporozoites were used to probe sporozoites of the rat coccidian, Eimeria nieschulzi. Analysis of silver stained gels revealed greater than 50 bands. Surface iodination revealed about 14 well labeled, and about 10 weakly labeled but potential, surface proteins. The most heavily labeled surface proteins had molecular masses of 60, 53-54, 45, 28, 23-24, 17, 15, 14, 13, and 12 kD. Following electrophoresis and Western blotting, 2 of the 12 125I labeled lectin probes bound to two bands on the blots, which collectively indicated that two bands were glycosylated. Concanavalin A (ConA) specifically recognized a band at 53 kD, which may represent a surface glycoprotein, and a lectin derived from Osage orange (MPA) bound to a single band at 82-88 kD, that may also be a surface molecule. Immunoblotting using sera collected from rats inoculated orally with oocysts, as well as sera from mice hyperimmunized with sporozoites, revealed that many surface molecules appear to be immunogenic.

  10. Eimeria collieie n. sp. (Apicomplexa:Eimeriidae) from the western long-necked turtle (Chelodina colliei).

    Science.gov (United States)

    Yang, Rongchang; Brice, Belinda; Elloit, Aileen; Lee, Elvina; Ryan, Una

    2015-07-01

    A new species, Eimeria collieie n. sp., is described from the western long-necked turtle (Chelodina colliei). Sporulated oocysts (n = 35) are spherical to subspherical, with colourless single layer oocyst wall, 0.6 ± 0.2 (0.4-0.7) µm thick. Oocyst with elongated ellipsoid sporocysts. Oocyst length, 29.8 ± 0.4 (28.2-31.0) µm; oocyst width, 29.4 ± 0.3 (28.0-30.8) µm; oocyst length/width (L/W) ratio, 1.0 ± 0.03 (1.0-1.05). Micropyle, oocyst residuum and polar granule were absent. Sporocysts with sporocyst residuum and 2 sporozoites. Sporocyst length, 21.6 ± 0.4 (21.2-22.0) µm; sporocyst width, 6.0 ± 0.3 (5.7-6.3) µm; sporocyst L/W ratio, 3.6 ± 0.2 (3.4-3.8). Stieda, parastieda and substieda bodies were absent. Sporozoite length, 14.0 ± 0.2 (13.8-14.2) µm; sporozoite width, 2.6 ± 0.2 (2.4-2.8) µm; sporozoite L/W ratio, 5.46 ± 0.10 (5.4-5.6). Molecular analysis was conducted at three loci: the 18S and 28S ribosomal RNA (rRNA), and the mitochondrial cytochrome oxidase gene (COI). At the 18S rRNA locus, E. collieie n. sp. shared 96.4% and 98.3% genetic similarity to E. ranae (GenBank accession number: EU717219) and E. arnyi (AY613853) respectively. At the 28S rRNA locus, E. collieie n. sp. shared 91.6% genetic similarity to E. papillata (GenBank accession number: GU593706) and phylogenetic analysis at this locus placed E. collieie n. sp. in aseparateclade. At the COI locus, E. collieie n. sp. shared 92.7% genetic similarity to Eimeria setonicis (GenBankaccession number: KF225638) from a quokka (Setonix brachyurus) in Western Australia. Reptile-derived sequences were not available for the 28S rRNA and the COI loci. Based on morphological and molecular data, this isolate is a new species of coccidian parasite that, to date, has only been found in western long-necked turtles.

  11. Complete mitochondrial genome sequences from five Eimeria species (Apicomplexa; Coccidia; Eimeriidae) infecting domestic turkeys

    OpenAIRE

    Ogedengbe, Mosun E.; El-Sherry, Shiem; Whale, Julia; Barta, John R.

    2014-01-01

    Background Clinical and subclinical coccidiosis is cosmopolitan and inflicts significant losses to the poultry industry globally. Seven named Eimeria species are responsible for coccidiosis in turkeys: Eimeria dispersa; Eimeria meleagrimitis; Eimeria gallopavonis; Eimeria meleagridis; Eimeria adenoeides; Eimeria innocua; and, Eimeria subrotunda. Although attempts have been made to characterize these parasites molecularly at the nuclear 18S rDNA and ITS loci, the maternally-derived and mitotic...

  12. Reclassification of Eimeria pogonae Walden (2009) as Choleoeimeria pogonae comb. nov. (Apicomplexa: Eimeriidae).

    Science.gov (United States)

    Szczepaniak, Klaudiusz Oktawian; Tomczuk, Krzysztof; Lojszczyk-Szczepaniak, Anna; Lopuszynski, Wojciech

    2016-02-01

    The presented paper provides a reclassification of Eimeria pogonae from Pogona vitticeps into the correct genus Choleoeimeria. A description of exogenous and endogenous stages of biliary coccidium is given. Sporulation of the oocysts was endogenous. The mature oocysts contained four sporocysts each with two sporozoites. Oocysts were ellipsoidal in shape, with average length/width ratio 1.7 and measured 28.4 (SD1.5) × 16.8 (SD 1.5). The micropyle, residuum, and polar granules were absent from the sporulated oocysts. Ovoidal in shape, sporosysts without Steida bodies contained residuum and two elongated and boat-shaped sporozoites. The endogenous stages of the coccidia were located mainly in the epithelium of bile ducts; however, single-epithelium cells of the gallbladder were also infected.

  13. Parasites and malignancies, a review, with emphasis on digestive cancer induced by Cryptosporidium parvum (Alveolata: Apicomplexa

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    Benamrouz S.

    2012-05-01

    Full Text Available The International Agency for Research on Cancer (IARC identifies ten infectious agents (viruses, bacteria, parasites able to induce cancer disease in humans. Among parasites, a carcinogenic role is currently recognized to the digenetic trematodes Schistosoma haematobium, leading to bladder cancer, and to Clonorchis sinensis or Opisthorchis viverrini, which cause cholangiocarcinoma. Furthermore, several reports suspected the potential association of other parasitic infections (due to Protozoan or Metazoan parasites with the development of neoplastic changes in the host tissues. The present work shortly reviewed available data on the involvement of parasites in neoplastic processes in humans or animals, and especially focused on the carcinogenic power of Cryptosporidium parvum infection. On the whole, infection seems to play a crucial role in the etiology of cancer.

  14. Cryptosporidium rubeyi n. sp. (Apicomplexa: Cryptosporidiidae in multiple Spermophilus ground squirrel species

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    Xunde Li

    2015-12-01

    Full Text Available Previously we reported the unique Cryptosporidium sp. “c” genotype (e.g., Sbey03c, Sbey05c, Sbld05c, Sltl05c from three species of Spermophilus ground squirrel (Spermophilus beecheyi, Spermophilus beldingi, Spermophilus lateralis located throughout California, USA. This follow-up work characterizes the morphology and animal infectivity of this novel genotype as the final step in proposing it as a new species of Cryptosporidium. Analysis of sequences of 18S rRNA, actin, and HSP70 genes of additional Cryptosporidium isolates from recently sampled California ground squirrels (S. beecheyi confirms the presence of the unique Sbey-c genotype in S. beecheyi. Phylogenetic and BLAST analysis indicates that the c-genotype in Spermophilus ground squirrels is distinct from Cryptosporidium species/genotypes from other host species currently available in GenBank. We propose to name this c-genotype found in Spermophilus ground squirrels as Cryptosporidium rubeyi n. sp. The mean size of C. rubeyi n. sp. oocysts is 4.67 (4.4–5.0 μm × 4.34 (4.0–5.0 μm, with a length/width index of 1.08 (n = 220. Oocysts of C. rubeyi n. sp. are not infectious to neonatal BALB/c mice and Holstein calves. GenBank accession numbers for C. rubeyi n. sp. are DQ295012, AY462233, and KM010224 for the 18S rRNA gene, KM010227 for the actin gene, and KM010229 for the HSP70 gene.

  15. KLOSSIELLA DULCIS N. SP. (APICOMPLEXA: KLOSSIELLIDAE) IN THE KIDNEYS OF PETAURUS BREVICEPS (MARSUPIALIA: PETAURIDAE).

    Science.gov (United States)

    Ardiaca, Maria; Bennett, Mark D; Montesinos, Andres; Juan-Sallés, Carles; Soriano-Navarro, Mario

    2016-06-01

    Two cases of renal klossiellosis were diagnosed by histopathology in pet sugar gliders (Petaurus breviceps). In both cases, parasites were associated with tubular dilation and mild interstitial nephritis. Rare schizonts were seen in the proximal convoluted renal tubular epithelium, whereas all other life cycle stages were found within distal convoluted tubule cells or the urinary space of the structures distal to the loop of Henle. Conventional optical and transmission electron microscopies were used to assess the life stages of the parasite. The morphologic characteristics and measurements observed differ from those of previously described species of Klossiella infecting marsupial hosts, and the name Klossiella dulcis n. sp. is hereby proposed. This is the first report of a Klossiella sp. infection in Petaurus breviceps .

  16. Lankesterella poeppigii n. sp. (Apicomplexa, Lankesterellidae from Bufo poeppigii (Tschudi, 1845 from Peru

    Directory of Open Access Journals (Sweden)

    Ilan Paperna

    2011-07-01

    Full Text Available Lankesterella poeppigii n. sp. is described from Bufo poeppigii (Tschudi, 1845 from Peru. Merogony and oogony occur in the capillary endothelium and the macrophages in the liver, spleen and kidneys. Meronts are oval, 25,2–29,4 x 15,7–16,8 μm in size and yield 35–46 merozoites. Oocysts are 26,3–29,4 x 15,1–17,6 μm in size; sporozoites 9,2-9,8 x 4,2–5,0 μm in size, assemble in macrophages. Released 8,7–9,8 x 2,8–3,1 μm sporozoites enter erythrocytes. L. poeppigii is compared with Lankesterella petiti Lainson & Paperna, 1995 infecting Bufo marinus (Linnaeus, 1758 in Brazil. The above mentioned specific characters, added to differences in hosts and geographical location warrant the description of Lankesterella poeppigii from B. poeppigii as a new species.

  17. Morphologic and morphometric analysis of Hepatozoon spp. (Apicomplexa, Hepatozoidae of snakes

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    Moço Tatiana Cristina

    2002-01-01

    Full Text Available Hepatozoon species are the most abundant hemoparasites of snakes. Its identification has been based mainly on the morphologic characterization of the gamonts in the peripheral blood of the vertebrate host and also of the cysts found in the internal organs of the vertebrate and invertebrate hosts. Using a computerized image analysis system, we studied five species of Hepatozoon from recently captured snakes in Botucatu, State of São Paulo, Brazil, to evaluate the importance of the morphology and morphometry of the gamonts for the characterization of Hepatozoon species and to analyze the morphologic changes induced in the erythrocytes by the parasite. The studied species were H. terzii of Boa constrictor amarali, Hepatozoon sp. of Crotalus durissusterrificus, H. philodryasi of Philodryas patagoniensis, and H. migonei and H. cyclagrasi of Hydrodynastes gigas. We observed three different groups, one of them including the species H. terzii, H. philodryasi and Hepatozoon sp. of C. durissus terrificus; and the other two consisting of H. migonei and H. cyclagrasi. Degree of alterations in the erythrocytes was variable and it may be useful for characterization of Hepatozoon species.

  18. Prevalence of Hepatozoon spp. (Apicomplexa, Hepatozoidae among recently captured Brazilian snakes

    Directory of Open Access Journals (Sweden)

    O'Dwyer L.H.

    2003-01-01

    Full Text Available The goal of this study was to determine the prevalence of Hepatozoon spp. infection in recently captured snakes from Botucatu, São Paulo State, Brazil. Blood was collected from all snakes by ventral tail venipuncture. Blood smears were air dried, fixed with methanol, and stained with 10% Giemsa solution. The slides were microscopically examined for detection of hemoparasites by light microscopy at 250x magnification. A total of 238 snakes from 23 species were examined, of which 135 (56.7% were venomous and 103 (43.3% non-venomous snakes. The more numerous venomous species sampled were Crotalus durissus terrificus (n=108 and Bothrops jararaca (n=17 and non-venomous snakes were Oxyrhopus guibei (n=35, Boa constrictor amarali (n=18, and Waglerophis merremi (n=13. Hepatozoon spp. infection was detected in 39 (16.4% snakes. The prevalence in venomous and non-venomous snakes was 20.0% and 11.7%, respectively. The highest prevalences observed were 38.9% for Boa constrictor amarali, 35.3% for Bothrops jararaca, and 19.4% for Crotalus durissus terrificus.

  19. First Molecular Identification of Sarcocystis ovicanis (Protozoa, Apicomplexa in the Brain of Sheep in Iran.

    Directory of Open Access Journals (Sweden)

    Mitra Salehi

    2014-06-01

    Full Text Available The objective of the present study was to survey the presence of Sarcocystis in sheep's brain in North Khorasan Province.In general, 80 samples of sheep's brain were collected from slaughtered sheep in slaughterhouses of North Khorasan Province. Tissue digestion method was used for observing bradyzoites in tissues. Histopathological processing tracing Sarcocystis and ensuing structural change in the brain tissue were conducted. PCR analysis was conducted on all the brain samples. Sequencing was done for one PCR product. Genotype was identified by Blast search and homology analysis.Sarcocystis spp. was found in one of the brain samples (1.25% using tissue digestion method. The presence of bradyzoite was also confirmed in the prepared histopathological sections. PCR analysis was positive in one of samples. Genotyping of one sample proved that Sarcocystis species was Sarcocystis ovicanis and the nucleotide sequence of this parasite was deposited in the GenBank database under accession number No.KF489431.Sarcocystis ovicanis can involve brain tissue of sheep and consequently causes clinical symptoms.

  20. Three new species of Coccidia (Apicomplexa: Eimeriidae) from Skinks, Lipinia spp. (Sauria: Scincidae), from Oceania

    Science.gov (United States)

    McAllister, Chris T.; Duszynski, Donald W.; Austin, Christopher C.; Fisher, Robert N.

    2013-01-01

    Between September 1991 and March 1993, 25 moth skinks (Lipinia noctua) were collected from various localities on the Cook Islands, Fiji, Papua New Guinea (PNG), and Vanuatu and examined for coccidians. In addition, a single Roux's lipinia skink (Lipinia rouxi) was collected from PNG and examined for coccidia. Sixteen (64%) L. noctua were found to harbor 2 new eimerians, and L. rouxi harbored another new Eimeria sp. Oocysts of Eimeria lipinia n. sp. from 9 (36%) L. noctua from the Cook Islands, Fiji, and PNG were subspherical with a bilayered wall and measured (L × W) 18.6 × 16.9 μm, with a L/W ratio of 1.1. Both micropyle and oocyst residuum were absent, but a polar granule was present. Oocysts of Eimeria melanesia n. sp. from 6 (24%) L. noctua from Fiji and Vanuatu and a single L. rouxi from PNG were subspherical to ellipsoidal with a bilayered wall and measured 19.8 × 17.5 μm, and L/W was 1.1. Both micropyle and oocyst residuum were absent, but a single or fragmented polar granule was present. Oocysts of Eimeria lessoni n. sp. from 1 (4%) L. noctua from PNG were cylindroidal with a bilayered wall and measured 28.1 × 15.7 μm, and L/W was 1.8. Both micropyle and oocyst residuum were absent, but a single polar granule was present. These represent the third report of Eimeria spp. reported from any host on PNG and the only coccidians, to our knowledge, ever described from L. noctua and L. rouxi and from the Cook Islands and Vanuatu.

  1. CRYPTOSPORIDIUM HOMINIS N. SP (APICOMPLEXA : CRYPTOSPORIDIIDAE) FROM HOMO SAPIENS. (R826138)

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    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  2. Sarcocystis heydorni, n. sp. (Apicomplexa: Sarcocystidae) with cattle (Bos taurus) and human (Homo sapiens) cycle.

    Science.gov (United States)

    Dubey, Jitender P; van Wilpe, Erna; Calero-Bernal, Rafael; Verma, Shiv Kumar; Fayer, Ronald

    2015-11-01

    Cattle (Bos taurus) are intermediate hosts for four species of Sarcocystis, namely Sarcocystis cruzi, Sarcocystis hirsuta, Sarcocystis hominis, and Sarcocystis rommeli. Of these four species, mature sarcocysts of S. cruzi are thin-walled (<1 μm), whereas S. hirsuta, S. hominis, and S. rommeli have thick walls (4 μm or more). Here, we describe a new species of Sarcocystis with thin-walled sarcocysts in cattle. Two newborn calves were fed with sporocysts from the feces of a human volunteer who had ingested raw beef. The calves were killed 111 and 222 days later. In addition to thick-walled sarcocysts of S. hominis, both calves were coinfected with a Sarcocystis species that had a thin-walled sarcocysts, distinct from S. cruzi. The sarcocysts were mature, microscopic, up to 80 μm wide, and up to 1060 μm long. By light microscopy, the sarcocyst wall was thin (<1 μm thick) and had minute protrusions. By transmission electron microscopy, the sarcocyst wall had short, conical villar protrusions (vp) that were up to 0.5 μm long and up to 0.5 μm wide, similar to type 29. The vp on the sarcocyst wall lacked microtubules but had six or more disc-shaped plaques. The ground substance layer was smooth, approximately 0.5 μm thick, and without microtubules. The bradyzoites were 8-11 μm long. The structure of the sarcocyst wall was distinct from any species of Sarcocystis reported from livestock. This unique species is named in honor of Dr. Alfred Otto Heydorn who provided the sporocysts.

  3. Besnoitia neotomofelis n. sp. (Protozoa: Apicomplexa) from the southern plains woodrat ( Neotoma micropus).

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    Dubey, J P; Yabsley, M J

    2010-10-01

    Certain species of the protozoan genus Besnoitia cause clinical disease in livestock and wildlife. In the present paper a new species, Besnoitia neotomofelis is described from the southern planes woodrat (Neotoma micropus). The parasite was detected by bioassay of woodrat tissues in outbred Swiss Webster mice in an attempt to isolate Toxoplasma gondii. Initially, the organism was misdiagnosed as T. gondii because it was highly pathogenic for mice and its tachyzoites resembled T. gondii tachyzoites. Further studies revealed that it differed structurally and biologically from T. gondii. Tachyzoites were successfully cultivated and maintained in vitro in bovine monocytes and African green monkey kidney cells, and in vivo in mice. Non-dividing, uninucleate tachyzoites were approximately 1 x 5 μm in size. Longitudinally-cut bradyzoites in tissue sections measured 1.5-1.6 x 7.7-9.3 μm. Tissue cysts were microscopic, up to 210 μm long, and were infective orally to mice. Cats fed tissue cysts shed unsporulated 13 x 14 μm sized oocysts. All mice inoculated with B. neotomofelis died of acute besnoitiosis, irrespective of the dose, and Norwegian rats became infected but remained asymptomatic. Entero-epithelial stages (schizonts, gamonts) were found in cats fed tissue cysts. Large (up to 40 x 50 μm) first-generation schizonts developed in the lamina propria of the small intestine of cats. A second generation of small sized (8 μm) schizonts containing 4-8 merozoites was detected in enterocytes of the small intestine. Gamonts and oocysts were seen in goblet cells of the small intestinal epithelium. Tachyzoites were present in mesenteric lymph nodes of cats. Phylogenetic analysis indicated that B. neotomofelis was related to other Besnoitia species from rodents, rabbits, and opossums. Besnoitia neotomofelis is distinct from the 3 other species of Besnoitia, B. wallacei, B. darlingi and B. oryctofelisi that utilize cats as a definitive host.

  4. Isospora bocamontensis (Protozoa: Apicomplexa in captive yellow cardinal Gubernatrix cristata (Passeriformes: Emberezidae

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    Larissa Quinto Pereira

    2013-03-01

    Full Text Available The yellow cardinal (Gubernatrix cristata is a passerine found in southern Brazil, especially along the border with Uruguay and Argentina. It is an endangered species and its population is decreasing. Among the parasites that affect passerines, the genus Isospora is the most easily found in both captive and free-living birds. This parasite commonly causes injury to the intestinal tissue and could occasionally affect other organs. In this work we examined the occurrence of coccidiosis in captive yellow cardinals and its association with factors such as sex, use of parasiticides, type of enclosure, contact with feces, type of food and cleaning frequency. We collected fecal samples of 45 yellow cardinals, healthy and kept in captivity, in late afternoon at the end of the reproductive period. The examination showed parasitic infection by Isospora bocamontensis in 44.5% of the birds. This infection is not influenced by the sex of birds, but is significantly affected by the type of enclosure, contact with the feces, use of parasiticides, type of food and cleaning frequency. The results indicate that to keep yellow cardinals captive, these factors must be observed.

  5. Sarcocystis heydorni, n. sp. (Apicomplexa: Protozoa) with cattle (Bos taurus) and human (Homo sapiens) cycle

    Science.gov (United States)

    Cattle (Bos taurus) are intermediate hosts for four species of Sarcocystis, S. cruzi, S. hirsuta, S. hominis, and S. rommeli. Of these four species, mature sarcocysts of S. cruzi are thin-walled (< 1µm) whereas S. hirsuta, S. hominis, and S. rommeli have thick walls (4 µm or more). Here we describe ...

  6. Caryospora uptoni n. sp. (Apicomplexa: Eimeriidae) from red-tailed hawks (Buteo jamaicensis borealis).

    Science.gov (United States)

    Lindsay, D S; Blagburn, B L

    1986-10-01

    Oocysts of Caryospora uptoni n. sp. were described from the feces of red-tailed hawks, Buteo jamaicensis borealis. Sporulated oocysts were spherical or subspherical and measured 28.1 by 26.4 micron. The oocyst wall was composed of a yellowish outer layer and brownish inner layer and was about 1.5 micron thick. Neither micropyle, polar granules, nor oocyst residuum were present. A single, spherical sporocyst 18.2 by 17.9 micron was present; a Stieda body was absent. A spherical eccentrically located sporocyst residuum was present in many sporocysts, but it degenerated to form a dispersed granular residuum in other sporocysts. Eight randomly arranged sporozoites, 12.6 by 4.2 micron, were present in each sporocyst; they contained a centrally or slightly posteriorly located nucleus.

  7. Eimeria auratae n. sp. (Apicomplexa: Eimeriidae) infecting the lizard Mabuya aurata in Saudi Arabia.

    Science.gov (United States)

    Alyousif, M S; AL-Rasheid, K A

    2001-03-01

    Eimeria auratae n. sp. was described from the gall bladder of the lizard Mabuya aurata collected at Al-Hofuf village, eastern region, Saudi Arabia. Morphology of sporulated as well as non-sporulated oocysts were studied. Sporulated oocysts were ellipsoidal 22-31.5x13.5-21.8 (27.7x18.5) microm with smooth brownish-yellow bilayered wall, 1.1 (0.9-1.3) microm. Micropyle, polar granule and oocyst residuum were absent. Sporocysts were ellipsoidal 10.5-12.8x7.5-9 (11.8x8.5) microm. Sporocyst residuum was present but Stieda body was absent. Sporozoites were crescent-shaped, blunt at one end and slightly tapered at the other. Eimeria species from Scincidae were compared.

  8. Sarcocystis canis n. sp. (Apicomplexa: Sarcocystidae), the etiologic agent of generalized coccidiosis in dogs.

    Science.gov (United States)

    Dubey, J P; Speer, C A

    1991-08-01

    Sarcocystis canis n. sp. is proposed for the protozoon associated with encephalitis, hepatitis, and generalized coccidiosis in dogs. Only asexual stages are known in macrophages, neurons, dermal, and other cells of the body. The parasite is located free in the host cell cytoplasm without a parasitophorous vacuole; schizonts divide by endopolygeny. Schizonts are 5-25 x 4-20 microns and contain 6-40 merozoites. Merozoites are approximately 5-7 microns x 1 micron and do not contain rhoptries. The parasite is PAS-negative and reacts with Sarcocystis cruzi antiserum but not with Toxoplasma gondii, Neospora caninum, or Caryospora bigenetica antisera in an immunohistochemical test.

  9. Schellackia (Apicomplexa: Eimeriidae of the brazilian tree-frog, Phrynohyas venulosa (Amphibia: Anura from Amazonian Brazil

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    I. Paperna

    1995-10-01

    Full Text Available Endogenous stages of a Schellackia species are described in histological sections of the intestine of the tree-frog, Phrynohyas venulosa, from North Brazil. Most oocysts sporulate within the epithelial cells of the gut, but a few were detected in the lamina propria.

  10. Life cycle of Cystoisospora felis (Coccidia: Apicomplexa) in cats and mice

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    Cystoisospora felis is a ubiquitous apicomplexan protozoon of cats. The endogenous development of C. felis was studied in cats after feeding them infected mice. For this, 5 newborn cats were killed at 24, 48, 72, 96, and 120 h after having been fed mesenteric lymph nodes and spleens of mice that wer...

  11. Effect of gregarines (Apicomplexa: Sporozoa) on survival and weight loss of Victorwithius similis (Arachnida: Pseudoscorpiones).

    Science.gov (United States)

    Bollatti, Fedra; Ceballos, Alejandra

    2014-03-01

    Gregarines are common intestinal parasites of numerous invertebrate groups. Their effects on host viability and development have been a matter of debate. Although they may not be lethal to the host, they can be harmless commensals, by affecting adaptive traits, or have a beneficial relationship with the host. This study focused on determining prevalence, intensity, and change in infection intensity over time by septate gregarines, and monitoring the effects on survival and weight loss in the pseudoscorpion Victorwithius similis. Individuals (n=24 females, n=55 males and n=41 tritonymphs) were captured in the field, transported to the vivarium and bred under laboratory conditions. A high prevalence of infection was found, with 77.27% of females, 62.50% of males and 73.53% of tritonymphs harboring intense infections. Of the infected pseudoscorpions, 62% of females, 58% of males and 71% of tritonymphs did not show changes in infection intensity over time. The group that maintained intense infections survived longer than those with less intense infections (χ(2)=8.642; p=0.035). Most of the results obtained indicate that relationship studied between gregarines and the pseudoscorpion V. similis might be a case of commensalism. This would explain why the infection level and prevalence was very high, as well as the apparent lack of direct costs to highly infected individuals those with infections.

  12. Cryptosporidium huwi n. sp. (Apicomplexa: Eimeriidae) from the guppy (Poecilia reticulata).

    Science.gov (United States)

    Ryan, Una; Paparini, Andrea; Tong, Kaising; Yang, Rongchang; Gibson-Kueh, Susan; O'Hara, Amanda; Lymbery, Alan; Xiao, Lihua

    2015-03-01

    The morphological, biological, and molecular characteristics of Cryptosporidium piscine genotype 1 from the guppy (Poecilia reticulata) are described, and the species name Cryptosporidium huwi n. sp. is proposed to reflect its genetic and biological differences from gastric and intestinal Cryptosporidium species. Oocysts of C.huwi n. sp. over-lap in size with Cryptosporidium molnari, measuring approximately 4.4-4.9 µm (mean 4.6) by 4.0-4.8 µm (mean 4.4 µm) with a length to width ratio of 1.04 (0.92-1.35) (n = 50). Similar to C.molnari, C.huwi n. sp. was identified in the stomach only and clusters of oogonial and sporogonial stages were identified deep within the epithelium. However, phylogenetic analysis of 18S rRNA sequences indicated that C. huwi n. sp. exhibited 8.5-9.2% and 3.5% genetic distance from C.molnari isolates and piscine genotype 7 respectively. At the actin locus, the genetic distance between C.huwi n. sp. and C.molnari was 16.6%. The genetic distance between C.huwi n. sp. and other Cryptosporidium species at the 18S locus was 13.2%-17% and at the actin locus was 18.9%-26.3%. Therefore C. huwi n. sp. is genetically distinct from previously described Cryptosporidium species.

  13. Tyzzeria parvula (Kotlan, 1933 Klimes, 1963 (Apicomplexa: Eimeriidae in the greylag goose (Anser anser Linnaeus, 1758 in southeastern Brazil Tyzzeria parvula (Kotlan, 1933 Klimes, 1963 (Apicomplexa: Eimeriidae no ganso cinzento (Anser anser Linnaeus, 1758 no sudeste do Brasil

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    Bruno P. Berto

    2007-09-01

    Full Text Available Tyzzeria parvula from the greylag goose (Anser anser is described in Southeastern Brazil. Oocysts are spherical to subspherical ranging from 12.4-180 to 10.7-15.9µm (15.4 X 13.4 µm, shape index 1.15, with a double layered wall 0.4 to 0.7 µm thick (n=20, outer smooth and colorless, inner pale greenish. Micropyle is absent, but oocyst residuum is present containing numerous granules and spherules. Surrounded by residuum there are eight sporozoites having one end round and other fine and slightly curved.Tyzzeria parvula é descrita no sudeste do Brasil em ganso doméstico, Anser anser. Os oocistos com parede constituída de duas membranas, a externa lisa e translúcida, e a interna verde pálido, variando de esféricos a subesféricos e sem micrópila. Os diâmetros, maior e menor mediram de 12,4 a 18,0 por 10,7 a 15,9µm (15,4 x 13,4µm respectivamente com índice morfométrico de 1,15. Possuíam oito esporozoítas livres dentro do oocisto embebidos pelo corpo residual do oocisto. Uma das extremidades dos esporozoítas era arredondadas, enquanto a outra era estreita e levemente curvada.

  14. Eimeria atlapetesi nom. nov., a replacement name for Eimeria pileata Soriano-Vargas et al., 2015 (Apicomplexa: Eimeriidae), preoccupied by Eimeria pileata Straneva and Kelley, 1979 (Apicomplexa: Eimeriidae), with observations on histopathology and phylogenetic analysis.

    Science.gov (United States)

    Soriano-Vargas, Edgardo; Salgado-Miranda, Celene; Zepeda-Velázquez, Andrea Paloma; Medina, Juan Pablo; Janczur, Mariusz Krzysztof; González-Gómez, Maricruz; Flores-Valle, Izanami Tereira; Berto, Bruno Pereira; Lopes, Carlos Wilson Gomes

    2017-01-31

    Eimeria pileata Soriano-Vargas, Medina, Salgado-Miranda, García-Conejo, Galindo-Sánchez, Janczur, Berto and Lopes, 2015 is a junior homonym of Eimeria pileata Straneva and Kelley, 1979 and needs to be replaced. This coccidium was described from a rufous-capped brush finch Atlapetes pileatus Wagler in the Nevado de Toluca Natural Protected Area, Mexico. Thus, to maintain the original intent of the specific epithet derived from the scientific name of the type-host, the name Eimeria atlapetesi nom. nov. is proposed as a replacement name. Additionally, the current work reports another rufous-capped brush finch A. pileatus parasitized by E. atlapetesi in co-infection with an Isospora sp., providing observations of histopathology and phylogenetic analysis of 18S ribosomal RNA (rRNA) gene from E. atlapetesi. Endogenous forms of E. atlapetesi and Isospora sp. were observed in intestinal sections. Few oocysts of Isospora sp. were observed; therefore they were not morphologically or molecularly identified. In return, E. atlapetesi was identified and it was phylogenetically close to Eimeria dispersa Tyzzer, 1929 from the domestic turkey Meleagris gallopavo Linnaeus.

  15. Coccidia of the collared peccary (Tayassu tajacu) in southern Texas with descriptions of three new species of Eimeria (Apicomplexa: Eimeriidae).

    Science.gov (United States)

    Wilber, P G; Hellgren, E C; Gabor, T M

    1996-08-01

    In February 1993, fresh fecal samples were collected from 47 collared peccaries (Tayassu tajacu) killed by hunters at the Chaparral Wildlife Management Area, southern Texas, USA. Five species of coccidia (Eimeria chaparralensis n. sp. [9/47, 19%], Eimeria dicotylensis n. sp. [21/47, 21%], Eimeria pecari n. sp. [2/47, 4%], Eimeria sp. [1/47, 2%], and Klossia sp. [1/47, 2%]) were observed. Measurements are in micron. Sporulated oocysts of E. chaparralensis are rough-walled, elongate ovoidal, 43.3 x 28.5 (37-52 x 26-35); sporocysts are elongate ellipsoidal 21.8 x 9.0 (16-27 x 7-12); micropyle (approximately 4.9), Stieda, and substieda body are present; sporocyst residuum is present in newly sporulated oocysts; polar granule and oocyst residuum are absent. Sporulated oocysts of E. dicotylensis are smooth-walled, ovoidal, 25.7 x 20.1 (23-29 x 17-23); sporocysts are ellipsoidal 13.0 x 6.9 (11-17 x 6-9); micropyle and oocyst residuum are absent; polar body sometimes present; Stieda body and sporocyst residuum always present. Sporulated oocysts of E. pecari are smooth-walled, elongate ellipsoidal, 26.8 x 18.1 (22-31 x 15-21); sporocysts are elongate ellipsoidal 16.4 x 5.9 (13-22 x 4-7); micropyle (approximately 5.8) with collar, Stieda body, substieda body, and sporocyst residuum are present; polar granule and small oocyst residuum sometimes present. There were no sex or age differences in prevalences of infection, and there were no positive or negative associations between any species of eimerian. The majority of hosts were infected with a single species of Eimeria. Overall prevalence of infection with eimerians was 23/47 (49%).

  16. Eimeria pavoaegyptica sp. nov. (Apicomplexa: Eimeriidae in faeces of Indian peacocks, Pavo cristatus Linnaeus, 1758 (Galliformes: Phasianidae from Egypt

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    Ismail Saad El-Shahawy

    2010-12-01

    Full Text Available Coprological examination of 15 Indian peacocks, Pavo cristatus, revealed the presence of a coccidium species of the genus Eimeria, which apparently represents a previously undescribed species. Sporulation is exogenous and fully developed oocysts of Eimeria pavoaegyptica sp. nov. are ellipsoidal, with a dimension of 15 (13-16 × 12 (10-12.9 μm and with a shape index of 1.25 (1-1.3. The sporulated oocysts have no micropyle but enclose one large rectangular-shaped polar granule and an oocyst residuum. The oocysts have a distinct two-layered wall, which is ~1.7 μm thick. The outer layer has a smooth texture; it fills ~¾ of the total thickness and appears bicolored. The sporocysts are boat-shaped, of about 10 (9-11 × 4 (4-4.7 μm; their average shape-index is 2.5 μm with a small pointed Stieda body and a smooth, thin single-layered wall. No substieda body is detected. The sporocysts contain numerous, nearly uniform granular residua. The sporozoites are banana-shaped, 6 × 3 μm and each has two different-sized refractile bodies.

  17. Endogenous Life Cycle of Eimeria marmosopos (Apicomplexa: Eimeriidae) from the Opossum, Didelphis marsupialis (Didelphimorphia: Didelphidae) in Costa Rica.

    Science.gov (United States)

    Chinchilla, Misael; Valerio, Idalia; Duszynski, Donald

    2015-08-01

    The endogenous life cycle of Eimeria marmosopos was studied in experimentally infected young opossums, Didelphis marsupialis . All the endogenous stages were located in the epithelial cells of villi in the small intestine. Giemsa-stained mucosal scrapings and histological sections were studied for the diagnosis of all the life cycle stages. Eimeria marmosopos has 3 generations of meronts (M) that differ by size, shape, and number of merozoites (m), which also differ in their size, shape, and location of their nuclei within the cytoplasm of the meronts. The 3 meront types, M(1)-M(3), respectively, had 8-15 (m(1)), 4-9 (m(2)), and 22-30 (m(3)) merozoites. Macrogametocytes and microgametocytes, as well as macrogametes and microgametes, completed the sexual cycle, finishing with the formation of unsporulated oocysts. This parasite's endogenous development produced severe intestinal lesions in experimentally infected opossums. There are 56 Eimeria species known from all marsupials worldwide, but this is the first complete life cycle in which both the asexual and sexual stages have been documented.

  18. Morphological and molecular characterization of Eimeria haematodi, coccidian parasite (Apicomplexa: Eimeriidae) in a rainbow lorikeet (Trichoglossus haematodus).

    Science.gov (United States)

    Yang, Rongchang; Brice, Belinda; Ryan, Una

    2015-06-01

    Eimeria haematodi was first described in 1977 from the rainbow lorikeet (Trichoglossus haematodus) in Papua New Guinea. In the present study, we re-describe this coccidian species morphologically and molecularly from a rainbow lorikeet bird in Western Australia (WA). The oocysts were ovoid to slightly piriform and measured 28.5-37.8 by 25.8-33.0 µm (33.3 by 28.1 µm). Oocyst wall was approximately 1.5 µm thick and bilayered. Micropyle (5-7 µm) and oocyst residuum (8.0-10.0 µm) present; polar granule was absent. Sporocysts ellipsoidal, 11.8-13.6 by 8.0-9.6 µm (12.2 by 8.3 µm), with thin convex Stieda body and granular sporocyst residuum (4.0-5.0 µm). Molecular characterization of E. haematodi was conducted at 18S ribosomal RNA and the mitochondrial cytochrome oxidase gene (COI) loci. At the 18S ribosomal RNA locus, E. haematodi shared 98.1% genetic similarity to E. alabamensis from cattle in New South Wales, Australia. At COI locus, E. haematodi was closest (92.3% similarity) to E. praecox from domestic chickens (Gallus gallus domesticus) from Canada and China.

  19. A New Species of Eimeria (Apicomplexa: Eimeriidae) from Green Frog, Lithobates clamitans (Anura: Ranidae) from Arkansas, U.S.A.

    Science.gov (United States)

    Mcallister, Chris T; Seville, R Scott; Bursey, Charles R; Trauth, Stanley E; Connior, Matthew B; Robison, Henry W

    2014-07-01

    Between April and October 2012, 20 juvenile and adult green frogs (Lithobates clamitans) were collected by hand or dipnet from 3 counties of Arkansas and examined for coccidial parasites. A single frog (5%) was found to be passing oocysts of a new eimerian species. Oocysts of Eimeria menaensis n. sp. were ellipsoidal to subspheroidal with a bilayered wall and measured (L × W) 25.4 × 15.6 (23-27 × 13-17) µm, with a L/W ratio of 1.6. A micropyle was absent but an oocyst residuum and polar granule were present. Sporocysts were spheroidal to subspheroidal and measured 5.0 × 5.0 (4-6) µm with L/W of 1.1. An indistinct Stieda body was present, but sub-and para-Stieda bodies were absent. The sporocyst residuum consisted of condensed granules dispersed between sporozoites. Sporozoites were elongate and attenuated at both ends with spheroidal anterior and posterior refractile bodies. This represents the second report of coccidia from L. clamitans and the first time a coccidian has been reported from a green frog from Arkansas.

  20. Microscopic and molecular characterization of Hepatozoon domerguei (Apicomplexa and Foleyella furcata (Nematoda in wild endemic reptiles from Madagascar

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    Maia João P.

    2014-01-01

    Full Text Available Madagascar is one of the world’s top twelve “megadiversity” hot spots hosting unique and threatened flora and fauna. Parasites are a major component of biodiversity but remain largely uncharacterized in wildlife. In this study we combine microscopic and molecular assessment of hemoparasites in endemic reptile species from Madagascar. We detected three distinct parasites: the apicomplexans Hepatozoon and Sarcocystis, and filarial nematodes. The prevalence and intensity of these apicomplexans were low overall, while microfilarial infections in chameleons were relatively high. We detected mixed infections of two Hepatozoon haplotypes in Madagascarophis colubrinus, and of Hepatozoon and microfilariae in a Furcifer sp. Phylogenetic analyses of Hepatozoon showed evidence of prey-predator transmission, with identical sequences found in the snakes M. colubrinus and Ithycyphus oursi, and their prey Furcifer sp. Based on previous studies regarding the life cycle of Hepatozoon domerguei Landau, Chabaud, Michel, and Brygoo, 1970 in these hosts and due to their morphological similarity, we propose that this Hepatozoon haplotype is Hepatozoon domerguei. Future studies, including the examination of invertebrate hosts, are needed to verify this preliminary taxonomic identification. A distinct hemogregarine haplotype was found in Oplurus sp., which displayed morphologically different gametocytes, some of which were apparently inside leukocytes. The Sarcocystis identified from Tracheloptychus petersi was identical to that reported in a North African snake, indicating that the same lineage is found in geographically distinct regions. By combining morphological and genetic information, Foleyella furcata (Linstow, 1899 filarial nematodes were identified in several Furcifer chameleons. This study provides insights into the distribution, diversity and host-parasite interactions of hemoparasites in wild reptile populations from Madagascar.

  1. Haemoproteus ilanpapernai n. sp. (Apicomplexa, Haemoproteidae) in Strix seloputo from Singapore: morphological description and reassignment of molecular data.

    Science.gov (United States)

    Karadjian, Grégory; Martinsen, Ellen; Duval, Linda; Chavatte, Jean-Marc; Landau, Irène

    2014-01-01

    Haemoproteus ilanpapernai Karadjian and Landau n. sp. from the Spotted Wood Owl, Strix seloputo, in Singapore is described from material from Ilan Paperna's collection of slides. The species was previously identified as Haemoproteus syrnii (Mayer, 1910). However, comparisons between the material from Strix seloputo and our own material from Strix aluco, the type host of H. syrnii, revealed morphological and molecular differences. H. ilanpapernai n. sp. differs morphologically from H. syrnii by the much smaller size of the gametocytes, the different position of the mature gametocytes in the erythrocyte (apical, subapical, or lateral in H. ilanpapernai vs. always lateral in H. syrnii), the effect on the erythrocyte nucleus (frequently tilted in H. ilanpapernai but not displaced laterally vs. straight and displaced laterally in H. syrnii) and characters of the pigment (aggregated in the gametocytes of H. ilanpapernai vs. dispersed in H. syrnii). A molecular analysis showed that the two species differ by 2.9% at the cyt b and 3.1% at the COI genes.

  2. Coccidia of New World passerine birds (Aves: Passeriformes): a review of Eimeria Schneider, 1875 and Isospora Schneider, 1881 (Apicomplexa: Eimeriidae).

    Science.gov (United States)

    Berto, Bruno P; Flausino, Walter; McIntosh, Douglas; Teixeira-Filho, Walter L; Lopes, Carlos W G

    2011-11-01

    In the New World, the avian order Passeriformes comprises 47 families and 2,453 species, yet to date only 21 (45%) of the families and 58 (2%) of the species have been examined for coccidia, and from these only two species of Eimeria Schneider, 1875 and 81 species of Isospora Schneider, 1881 have been described. This review contributes to our understanding of the morphology and systematics of coccidian parasites of passeriforms, providing a scientific basis for the identification of sporulated oöcysts recovered from the faeces of passerine birds from North, Central and South America. To this end, the coccidia were organised and grouped according to the family of the host, following the widely recognised concept of family-specificity and the updated systematics of the class Aves. Details of 83 eimeriid species are presented along with an illustration and tabulated data.

  3. Haemoproteus ilanpapernai n. sp. (Apicomplexa, Haemoproteidae in Strix seloputo from Singapore: morphological description and reassignment of molecular data

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    Karadjian Grégory

    2014-01-01

    Full Text Available Haemoproteus ilanpapernai Karadjian and Landau n. sp. from the Spotted Wood Owl, Strix seloputo, in Singapore is described from material from Ilan Paperna’s collection of slides. The species was previously identified as Haemoproteus syrnii (Mayer, 1910. However, comparisons between the material from Strix seloputo and our own material from Strix aluco, the type host of H. syrnii, revealed morphological and molecular differences. H. ilanpapernai n. sp. differs morphologically from H. syrnii by the much smaller size of the gametocytes, the different position of the mature gametocytes in the erythrocyte (apical, subapical, or lateral in H. ilanpapernai vs. always lateral in H. syrnii, the effect on the erythrocyte nucleus (frequently tilted in H. ilanpapernai but not displaced laterally vs. straight and displaced laterally in H. syrnii and characters of the pigment (aggregated in the gametocytes of H. ilanpapernai vs. dispersed in H. syrnii. A molecular analysis showed that the two species differ by 2.9% at the cyt b and 3.1% at the COI genes.

  4. Some new species of Caryospora (Apicomplexa: Eimeriidae from brazilian snakes, and a re-description of C. jararacae Carini, 1939

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    Ralph Lainson

    1991-09-01

    Full Text Available The mature ooxysts of six new species of Caryospora are described from the faeces of Brazilian snakes. They are differentiated from other species previously recorded from reptiles, largely on the size and shape of the oocyst and sporocyst, structure of the oocyst wall, and presence or absence of a polar body. C. paraensis n. sp., and C. carajasensis n. sp., are from the "false coral", Oxyrhopus petola digitalis; C. pseustesi n. sp., from the "egg-eater", Pseustes sulphureus sulphureus; C. epicratesi n. sp., from the "red boa", Epicrates cenchria cenchria; and C. micruri n. sp., and C. constancieae n. sp., from the "coral snake", Micrurus spixii spixii. A re-description is given of C. jararacae Carini, 1939, from the "jararaca" Bothrops atrox, embodying some additional morphological features.

  5. Two new species of Isospora (Apicomplexa: Eimeriidae) from skinks Emoia spp. (Sauria: Scincidae), from Fiji and Papua New Guinea

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    McAllister, Chris T.; Duszynski, Donald W.; Fisher, Robert N.

    2013-01-01

    Between September and October 1991 and again during September 1992, skinks (Emoia spp.) were collected from various localities on Fiji and Papua New Guinea (PNG) and examined for coccidians. One of 4 (25%) De Vis' emo skinks (Emoia pallidiceps) from PNG harbored an undescribed species of Isospora in its feces. Oocysts of Isospora grinbikpelapalai n. sp. were ellipsoidal to subspheroidal, 18.1 × 14.9 (17–20 × 14–16) μm, with a bilayered wall and a length/width index (L/W) of 1.2. Both micropyle and oocyst residuum were absent, but a prominent polar granule was present. Sporocysts were ovoidal, 10.7 × 7.6 (10–11 × 7–8) μm, with a L/W index of 1.4. Stieda and sub-Stieda bodies were present, but para-Stieda bodies were absent. The sporocyst residuum consisted of large scattered globules dispersed between sporozoites. Sporozoites were elongate with spheroidal anterior and posterior refractile bodies. Isospora grinbikpelapalai was also found in 1 of 2 (50%) Pope's emo skinks (Emoia popei) from PNG. One of 13 (8%) white-bellied copper-striped skinks (Emoia cyanura), from Fiji, was passing another undescribed species of Isospora in its feces. Oocysts of Isospora casei n. sp. were elongate, 31.8 × 21.3 (28–35 × 18–24) μm, with a bilayered wall and a L/W index of 1.5. Micropyle, oocyst residuum, and polar granule were all absent. Sporocysts were ovoidal, 15.3 × 10.6 (14–16 × 10–12) μm, with a L/W index of 1.4. Stieda and sub-Stieda bodies were present, but para-Stieda bodies were absent. The sporocyst residuum consisted of scattered globules among sporozoites or as a cluster surrounding sporozoites. Sporozoites were elongate with spheroidal anterior and posterior refractile bodies. Isospora casei was also found in 1 of 2 (50%) Fiji slender treeskinks (Emoia concolor) from Fiji. This represents the first report of coccidia from Emoia spp. and, to our knowledge, the initial documentation of reptilian coccidia from herpetofauna from Papua New Guinea.

  6. Host and environmental risk factors associated with Cryptosporidium scophthalmi (Apicomplexa) infection in cultured turbot, Psetta maxima (L.) (Pisces, Teleostei).

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    Alvarez-Pellitero, Pilar; Perez, Andrés; Quiroga, M Isabel; Redondo, M José; Vázquez, Sonia; Riaza, Ana; Palenzuela, Oswaldo; Sitjà-Bobadilla, Ariadna; Nieto, José M

    2009-11-12

    An epidemiological cohort study of Cryptosporidium scophthalmi in cultured turbot Psetta maxima L. of Northwestern Spain was conducted along a four-year period. Four different ongrowing cohorts were monitored monthly from introduction into the ongrowing tanks (10-50 g) until reaching market size (400-1400 g). The association of host and environmental factors with five categories of parasite abundance was assessed using a multivariable regression framework. Epidemiological factors assessed here were water temperature, weight, length, month of collection, season, age, origin, condition factor, water filtration, and status to the myxozoan Enteromyxum scophthalmi infection. E. scophthalmi was included into the analysis because it targets the same organ than C. scophthalmi and it was prevalent in the studied population. The multivariable analysis demonstrated the statistically significant association between several factors and parasite abundance. C. scophthalmi abundance was associated (P<0.05) with age, condition factor, season, and status to E. scophthalmi infection. Young animals, with poor condition factor, during spring or summer, and not infected with the myxozoan were most likely to be highly infected by C. scophthalmi. Inclusion of these four variables significantly (P<0.05) improved the model, compared to the model that did not include any of these epidemiological factors. Increasing levels of C. scophthalmi abundance were associated (P<0.01) with higher severity of C. scophthalmi-compatible lesions. The frequency of distribution of C. scophthalmi abundance was clearly right-skewed and fitted a negative binomial distribution, whereas the intensity of infection fitted a Poisson distribution. The quantification of the variance-to-mean ratio stratified by age demonstrated overdispersion for 8-16 months old fish, although this bivariate association is likely affected by several other factors, as suggested by the results of the multivariable analysis. The negative relation between C. scophthalmi abundance and status to E. scophthalmi infection suggests differences in the transmission, onset, and course of both infections. The coarse filtration used in some cohorts did not significantly affect the levels of infection. C. scophthalmi was probably introduced into the ongrowing tanks mainly with carrier fish, though the involvement of infective oocysts from the water supply cannot be disregarded. Infection prevalence and mean intensity decreased with fish age and a seasonal distribution was found. Results presented here will help to understand the epidemiology of C. scophthalmi in turbot, to estimate the expected levels of infection associated with presence or absence of epidemiological factors, and to quantify the impact that the disease may have on susceptible turbot populations. The multivariable model used here is more powerful than the visual inspection of graphics for exploring associations in cooperative processes and can be easily extended to the assessment of epidemiological associations in other population and parasitic diseases.

  7. Caryospora peneireiroi n. sp. (Apicomplexa: Eimeriidae) in the common kestrel, Falco tinnunculus (Falconiformes: Falconidae), in mainland Portugal.

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    Cardozo, Sergian Vianna; Berto, Bruno Pereira; Caetano, Inês; Maniero, Viviane Camara; Fonseca, Isabel Pereira da; Lopes, Carlos Wilson Gomes

    2016-06-07

    The common kestrel Falco tinnunculus Linnaeus, 1758, is a widespread raptor, native in Europe, Asia and Africa, and vagrant in the Americas. In the current work, 27 fecal samples were collected from common kestrels kept in the Lisbon Center for Wild Animal Recovery, located at Monsanto Forest Park, Lisbon, Portugal. Five (19%) of them were found to be passing an undescribed species of Caryospora in their feces. The oocysts of Caryospora peneireiroi n. sp. were ellipsoidal with a bilayered wall and measured 47.1 × 37.6 µm with a shape index of 1.25. No micropyle, oocyst residuum or polar granule was present. The sporocysts were subspherical, measuring 25.1 × 24.3 µm. Stieda, sub-Stieda and para-Stieda bodies were absent. The sporocyst residuum was composed of many homogenous globules scattered throughout the periphery of the sporocyst. This is the fourth caryosporan species reported from F. tinnunculus.

  8. Caryospora peneireiroi n. sp. (Apicomplexa: Eimeriidae in the common kestrel, Falco tinnunculus (Falconiformes: Falconidae, in mainland Portugal

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    Sergian Vianna Cardozo

    2016-01-01

    Full Text Available Abstract The common kestrel Falco tinnunculus Linnaeus, 1758, is a widespread raptor, native in Europe, Asia and Africa, and vagrant in the Americas. In the current work, 27 fecal samples were collected from common kestrels kept in the Lisbon Center for Wild Animal Recovery, located at Monsanto Forest Park, Lisbon, Portugal. Five (19% of them were found to be passing an undescribed species of Caryospora in their feces. The oocysts of Caryospora peneireiroi n. sp. were ellipsoidal with a bilayered wall and measured 47.1 × 37.6 µm with a shape index of 1.25. No micropyle, oocyst residuum or polar granule was present. The sporocysts were subspherical, measuring 25.1 × 24.3 µm. Stieda, sub-Stieda and para-Stieda bodies were absent. The sporocyst residuum was composed of many homogenous globules scattered throughout the periphery of the sporocyst. This is the fourth caryosporan species reported from F. tinnunculus.

  9. Rodents as intermediate hosts of Hepatozoon ayorgbor (Apicomplexa: Adeleina: Hepatozoidae) from the African ball python, Python regius?

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    Sloboda, Michal; Kamler, Martin; Bulantová, Jana; Votýpka, Jan; Modrý, David

    2008-03-01

    Two experimental trials were performed to elucidate the role of rodents in the life cycle of Hepatozoon species using snakes as intermediate hosts. In one trial, two ball pythons, Python regius Shaw, 1802 were force fed livers of laboratory mice previously inoculated with sporocysts of Hepatozoon ayorgbor Sloboda, Kamler, Bulantová, Votýpka et Modrý, 2007. Transmission was successful in these experimentally infected snakes as evidenced by the appearance of intraerythrocytic gamonts, which persisted until the end of trial, 12 months after inoculation. Developmental stages of haemogregarines were not observed in histological sections from mice. In another experimental trial, a presence of haemogregarine DNA in mice inoculated with H. ayorgbor was demonstrated by PCR in the liver, lungs and spleen.

  10. Tyzzeria boae n. sp., (Apicomplexa: Eimeriidae, a New Coccidium from the Kidney of the snake Boa constrictor constrictor (Serpentes: Boidae

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    Ralph Lainson

    1994-12-01

    Full Text Available A new species of Tyzzeria is described from the kidney of the snake Boa constrictor constrictor Linnaeus, from the State of Pará, north Brazil. Oocysts from the coacal contents matured in eight days, at approximately 24°C. They measured 19.0 x 18.0 (15.0 x 15.0 - 22.5 x 21.5 µm, shape-index (length/width 1.0 (1.0 - 1.1. The oocyst wall is of an extremely delicate single, colourless layer, with no micropyle. Division of the oocyst contents into the 8 naked sporozoites leaves a bulky, spherical oocyst residuum averaging 15.5 x 14.8 (13.5 x 13.5 - 18.5 x 17.5 µm; the sporozoites measure an average of 11.0 x 1.8 (8.5 x 1.25 - 12.5 x 2.0 µm, and possess both anterior and posterior refractile bodies. Tyzzeria boae n.sp. is unique among the recorded species of the genus by virtue of its development in the epithelial cells of the distal convoluted tubules and collecting tubules of the kidney: stages in the merogony and gametogony of the parasite are described and figured.

  11. Cryptosporidium proliferans n. sp. (Apicomplexa: Cryptosporidiidae: Molecular and Biological Evidence of Cryptic Species within Gastric Cryptosporidium of Mammals.

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    Martin Kváč

    Full Text Available The morphological, biological, and molecular characteristics of Cryptosporidium muris strain TS03 are described, and the species name Cryptosporidium proliferans n. sp. is proposed. Cryptosporidium proliferans obtained from a naturally infected East African mole rat (Tachyoryctes splendens in Kenya was propagated under laboratory conditions in rodents (SCID mice and southern multimammate mice, Mastomys coucha and used in experiments to examine oocyst morphology and transmission. DNA from the propagated C. proliferans isolate, and C. proliferans DNA isolated from the feces of an African buffalo (Syncerus caffer in Central African Republic, a donkey (Equus africanus in Algeria, and a domestic horse (Equus caballus in the Czech Republic were used for phylogenetic analyses. Oocysts of C. proliferans are morphologically distinguishable from C. parvum and C. muris HZ206, measuring 6.8-8.8 (mean = 7.7 μm × 4.8-6.2 μm (mean = 5.3 with a length to width ratio of 1.48 (n = 100. Experimental studies using an isolate originated from T. splendens have shown that the course of C. proliferans infection in rodent hosts differs from that of C. muris and C. andersoni. The prepatent period of 18-21 days post infection (DPI for C. proliferans in southern multimammate mice (Mastomys coucha was similar to that of C. andersoni and longer than the 6-8 DPI prepatent period for C. muris RN66 and HZ206 in the same host. Histopatologicaly, stomach glands of southern multimammate mice infected with C. proliferans were markedly dilated and filled with necrotic material, mucus, and numerous Cryptosporidium developmental stages. Epithelial cells of infected glands were atrophic, exhibited cuboidal or squamous metaplasia, and significantly proliferated into the lumen of the stomach, forming papillary structures. The epithelial height and stomach weight were six-fold greater than in non-infected controls. Phylogenetic analyses based on small subunit rRNA, Cryptosporidium oocyst wall protein, thrombospondin-related adhesive protein of Cryptosporidium-1, heat shock protein 70, actin, heat shock protein 90 (MS2, MS1, MS3, and M16 gene sequences revealed that C. proliferans is genetically distinct from C. muris and other previously described Cryptosporidium species.

  12. Two new species of Eimeria (Apicomplexa: Eimeriidae from Asian geoemydid turtles Kachuga tentoria and Melanochelys trijuga (Testudines: Geoemydidae

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    Široký P.

    2005-03-01

    Full Text Available Coprological examination of ten Pink-ringed tent turtles Kachuga tentoria circumdata, recently imported from India, and three Burmese black turtles Melanochelys trijuga edeniana, imported from Myanmar, revealed the presence of two new species of Eimeria. Oocysts of Eimeria kachua n. sp. from K. t. circumdata are broadly oval to subspherical, 15.3 (13-18 × 13.9 (12-16 μm, with polar granule and subspherical oocyst residuum. Sporocyst elongatelly oval to spindle-shaped, 8.7 (7.5-10 × 4.9 (4-6 μm, with a knoblike Stieda body, covered with fine membranous cupola-like structures. Thin walled oocysts of Eimeria patta n. sp. from M. t. edeniana, have an irregular shape, influenced by the position of sporocysts, frequently with lobular irregularities, 12.6 (11-16 × 9.1 (7.5-12 μm. Sporocysts are oval to ellipsoidal, 5.8 (5-7 × 4.2 (3.5-5 μm.

  13. A new species of Caryospora (Apicomplexa: Eimeriidae) from the bald eagle, Haliaeetus leucocephalus (Accipitriformes: Accipitridae), from Kansas.

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    McAllister, Chris T; Duszynski, Donald W; McKown, Richard D

    2013-04-01

    Between March 1989 and February 1994, 4 bald eagles ( Haliaeetus leucocephalus ) from various localities in Kansas were examined for coccidia. One (25%) of the bald eagles was found to be passing an undescribed species of Caryospora in its feces. Oocysts of Caryospora hanebrinki n. sp. are ellipsoidal to ovoidal with a bilayered wall and measure 48.1 × 42.1 μm with a shape index of 1.2. A micropyle, oocyst residuum, and polar granule were absent. Sporocysts are spheroidal, 24.8 μm wide. Stieda, substieda, and parastieda bodies were absent; a spheroidal sporocyst residuum is present; it measures 17.5 μm and is composed of many intact homogenous globules with a few dispersed in a loose spiral around the sporocysts. This is the first caryosporan documented from the bald eagle and is the largest known Caryospora from raptors.

  14. Novel anti-infective molecule from innate immune cells as an antibiotic-alternative to control infections caused by Apicomplexa

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    With increasing needs for the global animal industry to address the regulatory restrictions on the use of antibiotic growth promoters (AGPs) in animal production, there is much interest to find alternatives to AGPs. To develop alternatives to antibiotics against the major poultry parasitic disease, ...

  15. A new species of Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae) from Carlia spp. (Sauria: Scincidae) from Papua New Guinea

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    McAllister, Chris T.; Duszynski, Donald W.; Fisher, Robert N.; Austin, Christopher C.

    2013-01-01

    A new species of Eimeria Schneider, 1875 from rainbow skinks, Carlia ailanpalai Zug and Carlia eothen Zug is described from specimens collected in Papua New Guinea (PNG). Oöcysts of Eimeria zugi n. sp. from one of one (100%) C. eothen are ellipsoidal to cylindroidal, with a smooth, colourless, bi-layered wall, measure 25.1 × 15.5 μm and have a length/width ratio of 1.6. The micropyle and the oöcyst residuum are absent, but a polar granule is present. The sporocysts are ovoidal to ellipsoidal and 10.3 × 7.1 μm in size and do not contain Stieda, sub-Stieda or para-Stieda bodies; and the sporocyst residuum is composed of a compact mass of large globules. The sporozoites are elongate, 12.8 × 2.9 μm in size, and contain anterior and posterior refractile bodies with a nucleus between them. This is the ninth species of coccidium described from skinks from PNG, and the new species described herein is apparently endemic to the skink genus Carlia (Gray).

  16. Four new species of coccidia (Apicomplexa: Eimeriidae) from Owen Stanley Skinks, Papuascincus stanleyanus (Sauria: Scincidae), from Papua New Guinea

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    McAllister, Chris T.; Duszynski, Donald W.; Fisher, Robert N.; Austin, Christopher C.

    2014-01-01

    Between September and November 1991, 12 Owen Stanley skinks, Papuascincus stanleyanus (Booulenger) were collected from various localities on Papua New Guinea and examined for coccidians. Six (50%) were found to harbour four eimerians that we describe here as new. Oocysts of Eimeria burseyi sp. n. were elongate to ellipsoidal with a bilayered wall and measured (length x width, L x W) 36.0 x 24.0 microm, with a L/W ratio of 1.5. Both micropyle and oocyst residuum were absent, but a polar granule was present. Oocysts of Eimeria goldbergi sp. n. were ellipsoidal, with a bilayered wall, and measured 21.4 x 16.1 microm; L/W ratio was 1.3. Both micropyle and oocyst residuum were absent, but a single or fragmented polar granule was present. Oocysts of Eimeria boulengeri sp. n. were spheroidal to slightly subspheroidal, with a thin, single-layered wall that readily collapses, and measured 16.0 microm, L/W ratio was 1.0. Both micropyle and oocyst residuum were absent, but usually one (sometimes two) polar granule(s) were present. Oocysts of Eimeria niuginiensis sp. n. were oblong to tapered with a bilayered wall, and measured 20.0 x 13.1 microm; L/W ratio was 1.5. A micropyle, oocyst residuum and polar granule were absent. To our knowledge, these represent the only coccidians ever described from P. stanleyanus.

  17. Two new species of Eimeria (Apicomplexa, Eimeriidae) from tree skinks, Prasinohaema spp. (Sauria: Scincidae), from Papua New Guinea

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    McAllister, Chris T.; Duszynski, Donald W.; Fisher, Robert N.; Austin, Christopher C.

    2014-01-01

    Between September 1991 and June 1992, feces from 4 species of tree skinks, Prasinohaema spp. from Papua New Guinea, were collected and examined for coccidia. Two species, P. flavipes and P. prehensicauda were found to harbor eimerians which are described as new. Oocysts of Eimeria krausi sp. nov. from P. flavipes were ellipsoidal to subspheroidal with a smooth bilayered wall and measured (L × W) 19.2 × 16.9 μm, with a length/width (L/W) ratio of 1.1. Micropyle and oocyst residuum were absent but a fragmented polar granule was present. Sporocysts were ellipsoidal, 9.7 × 6.7 μm, L/W of 1.5. Stieda, subStieda and paraStieda bodies were absent. The sporocyst residuum was composed of many small granules in a compact mass between sporozoites. The sporozoites were sausage-shaped, 11.7 × 2.7 μm, in situ, with an ellipsoidal posterior refractile body and a spheroidal anterior refractile body. Oocysts of Eimeria greeri sp. nov. from P. prehensicauda were ellipsoidal with a smooth bilayered wall, (L × W) 23.0 × 18.3 μm, with a L/W of 1.3. Micropyle and oocyst residuum were absent but a fragmented polar granule was present. Sporocysts were ellipsoidal, 9.7 × 8.4 μm, with a L/W of 1.2. Stieda, subStieda and paraStieda bodies were absent. The sporocyst residuum was composed of many large granules in a compact mass between sporozoites. The sporozoites were sausage-shaped, with an ellipsoidal posterior refractile body and a spheroidal anterior refractile body. We document here the first report of coccidia from skinks of the genus Prasinohaema.

  18. Hemolivia mauritanica (Haemogregarinidae: Apicomplexa infection in the tortoise Testudo graeca in the Near East with data on sporogonous development in the tick vector Hyalomna aegyptium

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    Paperna I.

    2006-12-01

    Full Text Available Testudo graeca tortoises were collected in the northern and southern Golan Heights (Israeli occupied territory of south Syria, and various locations in Israel and Palestine. Hyalomma aegyptium ticks were found only on Golan Height tortoises, and only the tortoises and ticks from the northern Golan Heights were infected with Hemolivia mauritanica. Tortoises became infected after ingesting infected ticks. Male ticks carrying sporocysts, which remain attached to tortoises for extended durations, apparently served as the source for dissemination of new infections among tortoises. Sporogenesis followed the pattern observed in the two other known species of Hemolivia, though there was some evident variation in fine-structural detail. The sutural slit detected in the H. mauritanica mature sporocyst wall was reminiscent of the suture characteristic of Coccidia of heterothermic vertebrate hosts; it could be a common ancestral character for both hemogregarines and Coccidia.

  19. Morphological and molecular characterization of Choleoeimeria pogonae n. sp. coccidian parasite (Apicomplexa: Eimeriidae, 1989, Paperna and Landsberg) in a western bearded dragon (Pogona minor minor).

    Science.gov (United States)

    Yang, Rongchang; Brice, Belinda; Ryan, Una

    2016-01-01

    A new species, Choleoeimeria pogonae n. sp. is described from a Western bearded dragon (Pogona minor minor) in Western Australia. Sporulated oocysts (n = 48) were cylindroidal in shape. Oocyst length, 27.0 (26.0-28.3) μm, oocyst width, 15.2 (14.0-16.5) μm, oocyst length/width ratio (L/W) 1.8 (1.6-1.9), each with 4 sporocysts (Eimeria-like) and a polar granule, but lacking a micropyle and oocyst residuum. Sporocysts are ovoidal in shape, sporocyst length, 10.0 (9.0-11.0) μm, sporocyst width 8.5 (7.0-9.5) μm, sporocyst L/W ratio, 1.2 (1.1-1.3). Stieda, substieda and parasubstieda bodies were all absent. Molecular analysis was conducted at the 18S rRNA and cytochrome c oxidase I (COI) loci. Phylogenetic analysis of 18S sequences revealed that C. pogonae n. sp. grouped together with another four Choleoeimeria spp. and exhibited 99.1%-99.4% genetic similarity. At the COI locus, C. pogonae n. sp. was in an independent clade and had the highest similarity (80.4%) to Eimeria cf. mivati from a chicken (Gallus gallus domesticus). According to the morphological and molecular data, this isolate is a new species of coccidian parasite. This study further supports the taxonomy of Choleoeimeria spp. as a new genus based on molecular phylogenetic analysis.

  20. Description of the Oocysts of Three New Species of Eimeria (Apicomplexa: Eimeriidae from Iguanid Lizards (Sauria: Iguanidae of Central and South America

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    Daszak P

    1998-01-01

    Full Text Available Three new species of Eimeria are described from iguanid lizards of Central and South America. The oocysts of each species have no micropyles or residua and the sporocysts lack Stieda bodies, but all have a sporocyst residuum. Eimeria sanctaluciae n.sp. was found in the St. Lucia tree lizard, Anolis luciae, collected from the Maria Islands, Lesser Antilles. The oocysts are spherical to subspherical, averaging 17.3 x 16.5 µm, with a single layered colourless wall; about 60% contain polar granules. The sporocysts are ellipsoidal and average 7.7 x 5.5 µm. Eimeria liolaemi n.sp. was recovered from the blue-gold swift, Liolaemus taenius, from Chile. The oocysts are spherical to subspherical, measuring 21 x 20.1 µm with a single-layered colourless wall. The sporocysts are subspherical and average 7.4 x 6.8 µm. Eimeria caesicia n.sp. is described from the Brazilian collared iguanid, Tropidurus torquatus. The oocysts measure 27.4 x 23.7 µm, are spherical to subspherical, with a bilayered wall, the outer surface of which appears pale blue in colour, the thin, inner wall appearing brown, when viewed by direct light under the optical microscope. The sporocysts are subspherical and average 9.4 x 7.2 µm. Unnamed polysporocystid oocysts with dizoic sporocysts are reported from the faeces of the lesser St. Vincent tree lizard, Anolis trinitatis and the possibility of spurious parasitism briefly discussed. In addition, oocysts of an unnamed Isospora sp. with a smooth oocyst wall which closely resembles I. reui were recovered from A. trinitatis.

  1. Clínica e hematologia de Bos indicus, Bos taurus e Bubalus bubalis inoculados com oocistos de Toxoplasma gondii (Apicomplexa: Toxoplasmatinae

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    Oliveira Francisco Carlos Rodrigues de

    2001-01-01

    Full Text Available Três animais de cada espécie (Bos indicus, Bos taurus e Bubalus bubalis foram inoculados, via oral, com 2,0 x 10(5 oocistos de Toxoplasma gondii. Seis outros animais, dois de cada espécie, foram mantidos como testemunhas. As alterações clínicas surgidas a partir do 3º dia após inoculação (DAI foram: hipertermia, taquicardia, taquipnéia, anorexia, prostração, corrimento nasal e lacrimejamento. Estes sinais foram mais evidentes nos taurinos, espécie que apresentou, ainda, diarréia, fotofobia e conjuntivite. Foi possível isolar T. gondii da corrente sangüínea em todas as espécies. Nos taurinos, a partir do 5º DAI até o final do experimento, o parasito foi isolado de todas as amostras de sangue colhidas semanalmente, com exceção do 14º, 35º e 63º DAI. Os bubalinos apresentaram parasitemia no 7º, 14º, 35º e 70º DAI e os zebuínos apenas no 7º e 28º DAI, correspondendo aos picos de temperatura, em todas as espécies, sendo mais evidente em taurinos. Os parâmetros clínico-laboratoriais demonstraram que os taurinos foram mais sensíveis ao T. gondii do que os zebuínos e estes não diferiram significativamente dos bubalinos, que tiveram aparente normalidade clínico-laboratorial.

  2. Cyrilia sp. (Apicomplexa: Haemogregarinidae in the Amazonian freshwater stingray Potamotrygon wallacei (cururu stingray in different hydrological phases of the Rio Negro

    Directory of Open Access Journals (Sweden)

    A. T. Oliveira

    Full Text Available Abstract Intraerythrocytic parasites are frequently found in fish, including elasmobranchs. The Amazonian rivers present well defined annual hydrological cycles that results in drastic modifications of the environmental conditions with deep implications in the life cycle of the whole associated biota in those fluvial systems. The freshwater stingray Potamotrygon wallacei (stingray cururu is a new species restricted to the Middle Rio Negro basin and it is subject to strong alterations in their natural habitats (igapós a result of the constant variations in the water level of Rio Negro. This work demonstrates the occurrence of intraerythrocytic parasite Cyrilia sp. in this stingray species. Additionally, the prevalence and quantification of hemoparasites in different phases of Rio Negro were also established. Field sampling was carried in the Archipelago of Mariuá, Middle Rio Negro, involving different stages of the water cycle. The intraerythrocytic parasites were quantified by direct counting in blood smears using a total counting of 2000 erythrocytes in each blood smear. The presence of parasites intraerythrocytic generates changes in the morphology of blood cell. The largest amount of the hemoparasites was recorded in the drought period. We observed a decreasing tendency in the number of parasites in the blood between the drought periods and inundation. We concluded that the level of Negro River influences the incidence of intraerythrocytic parasites in the cururu stingray and the drought represents the period of larger susceptibility to the infestation.

  3. Mattesia weiseri sp. nov., a new neogregarine (Apicomplexa: Lipotrophidae) pathogen of the great spruce bark beetle, Dendroctonus micans (Coleoptera: Curculionidae, Scolytinae).

    Science.gov (United States)

    Yaman, Mustafa; Radek, Renate

    2015-08-01

    A new neogregarine pathogen of the great spruce bark beetle, Dendroctonus micans (Coleoptera: Curculionidae, Scolytinae), is described based on light microscopy and ultrastructural characteristics. The pathogen infects the fat body and the hemolymph of the beetle. The infection was nonsynchronous so that different developmental stages could be observed simultaneously in the hemolymph. All life stages from sporozoite to oocyst of the pathogen including micronuclear and macronuclear merozoites were detected. The sporozoites measured about 8.7 × 1.9 μm and trophozoites, 11.9 × 3.3 μm. Micronuclear merozoites seen in the hemolymph were motile, elongate, slightly broader at the anterior pole, and measured 18.4 × 2.0 μm. Macronuclear merozoites had a size of ca. 16.4 × 2.3 μm. Gametogamy results in the formation of two paired oocysts within a gametocyst. The lemon-shaped oocyst measured 10.9 × 6.1 μm and had a very thick wall (375-450 nm). All morphological and ultrastructural characteristics of the life cycle stages indicate that the described neogregarine in D. micans is clearly different from known Mattesia species infecting bark beetles, and from any other described Mattesia spp. Therefore, we create a new species, Mattesia weiseri sp. nov.

  4. Evolutionary plasticity in coccidia - striking morphological similarity of unrelated coccidia (apicomplexa) from related hosts: Eimeria spp. from African and Asian Pangolins (Mammalia: Pholidota).

    Science.gov (United States)

    Jirků, Miloslav; Kvičerová, Jana; Modrý, David; Hypša, Václav

    2013-07-01

    Two morphologically similar, but phylogenetically unrelated Eimeria species from ancient mammals, African Tree Pangolin Phataginus tricuspis and Sunda Pangolin Manis javanica (Pholidota: Manidae), from two distant biogeographic realms (Afrotropical and Oriental), are characterized and compared morphologically and molecularly. Phylogenetic analyses produced an unstable topology. However, while precise position of the two Eimeria species from pangolins could not be firmly established due to the lack of related taxa, it is evident that they are not closely related and do not fall into any of the so far recognized eimerian lineages. Moreover, an eimerian found in P. tricuspis is described as a new species Eimeria nkaka n. sp., based on morphology of oocysts, endogenous developmental stages and sequence data.

  5. Morphological and molecular characterization of Eimeria paludosa coccidian parasite (Apicomplexa:Eimeriidae) in a dusky moorhen (Gallinula tenebrosa, Gould, 1846) in Australia.

    Science.gov (United States)

    Yang, Rongchang; Brice, Belinda; Elloit, Aileen; Lee, Elvina; Ryan, Una

    2014-12-01

    An Eimeria species is described from a dusky moorhen (Gallinula tenebrosa). Sporulated oocysts (n = 40) are ovoid, with a pitted single-layered oocyst wall in young oocysts and a relatively smooth wall in the mature oocysts. Oocyst wall was 1.0 µm thick, oocysts measured 17.3 × 13.3 (16.3-17.9 × 12.7-13.9) µm, oocyst length/width (L/W) ratio, 1.3. Oocyst residuum was absent. A large polar granule was always observed in the centre of the micropyle and many small polar granules were observed when the focus was on the wall. Sporocysts are elongate-ovoid, 8.4 × 5.1 (8.0-8.9 × 4.9-5.5) µm, sporocyst L/W ratio, 1.6 (1.5-1.8), sporocyst residuum was present, composed of numerous granules in a spherical or ovoid mass. Each sporocyst contained 2 elongate sporozoites, 7.7 × 2.6 (7-10 × 2.2-3) µm. A spherical-ellipsoid posterior refractile body was found in the sporozoites. A nucleus is located immediately anterior to the posterior refractile body. When the oocyst measurements and features were compared with valid Eimeria species from hosts in the Rallidae family, this Eimeria species was identified as E. paludosa. This is the first report of E. paludosa in Australia and the dusky moorhen (Gallinula tenebrosa) in a new host for this species. Molecular analysis was conducted at three loci; the 18S and 28S ribosomal RNA genes and the mitochondrial cytochrome oxidase gene (COI). At the 18 S locus, E. paludosa shared 97.3% genetic similarity with Eimeria gruis (GenBank accession number: AB544336). It also shared 99.2% genetic similarity with Eimeria crecis (GenBank accession numbers: HE653904 and HE653905) and 98.5% similarity with Eimeria nenei (GenBank accession numbers: HE653906), both of which were identified from a corncrake (Crex crex) in the United Kingdom. At the 28S locus, E. paludosa shared 91.4% similarity with E. papillata from a chicken (Gallus gallus) in the USA. At COI locus, E. paludosa was in a clade by itself and shared 87.2% similarity with E. irresidua, from a European rabbit (Oryctolagus cuniculus) from the Czech Republic. This is the first molecular characterization of E. paludosa.

  6. Intestinal Coccidia (Apicomplexa: Eimeriidae of Brazilian Lizards. Eimeria carmelinoi n.sp., from Kentropyx calcarata and Acroeimeria paraensis n.sp. from Cnemidophorus lemniscatus lemniscatus (Lacertilia: Teiidae

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    Lainson Ralph

    2002-01-01

    Full Text Available Eimeria carmelinoi n.sp., is described in the teiid lizard Kentropyx calcarata Spix, 1825 from north Brazil. Oocysts subspherical to spherical, averaging 21.25 x 20.15 µm. Oocyst wall smooth, colourless and devoid of striae or micropyle. No polar body or conspicuous oocystic residuum, but frequently a small number of fine granules in Brownian movement. Sporocysts, averaging 10.1 x 9 µm, are without a Stieda body. Endogenous stages characteristic of the genus: intra-cytoplasmic, within the epithelial cells of the ileum and above the host cell nucleus. A re-description is given of a parasite previously described as Eimeria cnemidophori, in the teiid lizard Cnemidophorus lemniscatus lemniscatus. A study of the endogenous stages in the ileum necessitates renaming this coccidian as Acroeimeria cnemidophori (Carini, 1941 nov.comb., and suggests that Acroeimeria pintoi Lainson & Paperna, 1999 in the teiid Ameiva ameiva is a synonym of A. cnemidophori. A further intestinal coccidian, Acroeimeria paraensis n.sp. is described in C. l. lemniscatus, frequently as a mixed infection with A. cnemidophori. Mature oocysts, averaging 24.4 x 21.8 µm, have a single-layered, smooth, colourless wall with no micropyle or striae. No polar body, but the frequent presence of a small number of fine granules exhibiting Brownian movements. Sporocysts 9 x 8, without a Stieda body. Endogenous stages epicytoplasmic, characteristic of the genus, in the upper ileum. The importance of a study of the endogenous stages of eimeriid coccidia is discussed.

  7. Morphological and molecular characterization of Eimeria labbeana-like (Apicomplexa:Eimeriidae) in a domestic pigeon (Columba livia domestica, Gmelin, 1789) in Australia.

    Science.gov (United States)

    Yang, Rongchang; Brice, Belinda; Elloit, Aileen; Ryan, Una

    2016-07-01

    An Eimeria species is described from a domestic pigeon (Columba livia domestica). Sporulated oocysts (n = 35) were subspherical, with a smooth bi-layered oocyst wall (1.0 μm thick). Oocysts measured 20.2 × 16.1 (22.0-18.9 × 15.7-18.9) μm, oocyst length/width (L/W) ratio, 1.38. Oocyst residuum and a polar granule were present. The micropyle was absent. Sporocysts are elongate-ovoid, 13.0 × 6.1 (14.5-12.5 × 5.5-7.0) μm, sporocyst L/W ratio, 2.13 (2.0-2.2), sporocyst residuum was present, composed of numerous granules in a spherical or ovoid mass. Each sporocyst contained 2 banana-shaped sporozoites, 12.3 × 3.5 (11.8-13.0 × 3.3-3.6) μm. A spherical-ellipsoid posterior refractile body was found in the sporozoites. A nucleus was located immediately anterior to the posterior refractile body. Molecular analysis was conducted at three loci; the 18S and 28S ribosomal RNA genes and the mitochondrial cytochrome oxidase gene (COI). At the 18S locus, the new isolate shared 98.0% genetic similarity with three Isospora isolates from Japan from the domestic pigeon (Columba livia domestica). At the 28S locus, it grouped separately and shared 92.4% and 92.5% genetic similarity with Isospora anthochaerae (KF766053) from a red wattlebird (Anthochaera carunculata) from Australia and an Isospora sp. (MS-2003 - AY283845) from a Himalayan grey-headed bullfinch (Pyrrhula erythaca) respectively. At COI locus, this new isolate was in a separate clade and shared 95.6% and 90.0% similarity respectively with Eimeria tiliquae n. sp. from a shingleback skink in Australia and an Eimeria sp. from a common pheasant (Phasianus colchicus) from America. Based on the morphological data, this isolate is most similar to Eimeria labbeana. As no molecular data for E. labbeana is available and previous morphological data is incomplete, we refer to the current isolate as E. labbeana-like.

  8. Molecular and phylogenetic characterizations of an Eimeria krijgsmanni Yakimoff & Gouseff, 1938 (Apicomplexa: Eimeriidae) mouse intestinal protozoan parasite by partial 18S ribosomal RNA gene sequence analysis.

    Science.gov (United States)

    Takeo, Toshinori; Tanaka, Tetsuya; Matsubayashi, Makoto; Maeda, Hiroki; Kusakisako, Kodai; Matsui, Toshihiro; Mochizuki, Masami; Matsuo, Tomohide

    2014-08-01

    Previously, we characterized an undocumented strain of Eimeria krijgsmanni by morphological and biological features. Here, we present a detailed molecular phylogenetic analysis of this organism. Namely, 18S ribosomal RNA gene (rDNA) sequences of E. krijgsmanni were analyzed to incorporate this species into a comprehensive Eimeria phylogeny. As a result, partial 18S rDNA sequence from E. krijgsmanni was successfully determined, and two different types, Type A and Type B, that differed by 1 base pair were identified. E. krijgsmanni was originally isolated from a single oocyst, and thus the result show that the two types might have allelic sequence heterogeneity in the 18S rDNA. Based on phylogenetic analyses, the two types of E. krijgsmanni 18S rDNA formed one of two clades among murine Eimeria spp.; these Eimeria clades reflected morphological similarity among the Eimeria spp. This is the third molecular phylogenetic characterization of a murine Eimeria spp. in addition to E. falciformis and E. papillata.

  9. Avaliação fisiopatológica de coelhos (Oryctolagus cuniculus) infectados experimentalmente com oocistos esporulados de Eimeria stiedae (APICOMPLEXA: EIMERIIDAE)

    OpenAIRE

    Freitas,Fagner Luiz da Costa

    2009-01-01

    A infecção experimental por Eimeria stiedae em coelhos foi realizada com o objetivo de avaliar os sinais clínicos, alterações hematológicas, metabólicas e anatomopatológicas. Foram utilizados 50 coelhos, raça Nova Zelândia, brancos, com idade entre 40 - 60 dias e de pesos semelhantes. Os animais foram randomizados com relação ao peso e distribuídos em 2 grupos experimentais: grupo infectado, inoculado com 1ml de solução contendo 1x104 oocistos esporulados de E. stiedae; grupo controle, inocul...

  10. Cyrilia sp. (Apicomplexa: Haemogregarinidae) in the Amazonian freshwater stingray Potamotrygon wallacei (cururu stingray) in different hydrological phases of the Rio Negro.

    Science.gov (United States)

    Oliveira, A T; Araújo, M L G; Pantoja-Lima, J; Aride, P H R; Tavares-Dias, M; Brinn, R P; Marcon, J L

    2016-08-15

    Intraerythrocytic parasites are frequently found in fish, including elasmobranchs. The Amazonian rivers present well defined annual hydrological cycles that results in drastic modifications of the environmental conditions with deep implications in the life cycle of the whole associated biota in those fluvial systems. The freshwater stingray Potamotrygon wallacei (stingray cururu) is a new species restricted to the Middle Rio Negro basin and it is subject to strong alterations in their natural habitats (igapós) a result of the constant variations in the water level of Rio Negro. This work demonstrates the occurrence of intraerythrocytic parasite Cyrilia sp. in this stingray species. Additionally, the prevalence and quantification of hemoparasites in different phases of Rio Negro were also established. Field sampling was carried in the Archipelago of Mariuá, Middle Rio Negro, involving different stages of the water cycle. The intraerythrocytic parasites were quantified by direct counting in blood smears using a total counting of 2000 erythrocytes in each blood smear. The presence of parasites intraerythrocytic generates changes in the morphology of blood cell. The largest amount of the hemoparasites was recorded in the drought period. We observed a decreasing tendency in the number of parasites in the blood between the drought periods and inundation. We concluded that the level of Negro River influences the incidence of intraerythrocytic parasites in the cururu stingray and the drought represents the period of larger susceptibility to the infestation.

  11. First report and description of a Cyrilia sp. (Apicomplexa: Haemogregarinidae) from a freshwater Cururu Stingray Potamotrygon cf. histrix (Elasmobranchii: Potamotrygonidae), from the Amazon Region, Brazil.

    Science.gov (United States)

    Magro, N M; de Oliveira, A T; O'Dwyer, L H

    2016-08-01

    A haemogregarine is described in 12 cururu stingray (Potamotrygon cf. histrix), from Mariuá Archipelago, Negro River, in the Brazilian Amazon Basin. All animals, both male and female, were parasitized by the haemogregarine and parasitaemia varied between 0.8% and 10% of erythrocytes. The stages observed included trophozoites or merozoites, suspected meronts, and gamonts presumed to be of two types, macrogamonts and microgamonts. Most stages were observed inside mature erythrocytes, while others were extracellular. The stages observed were most similar to those characteristics of the genus Cyrilia, than to any other fish haemogregarine and may represent a new Cyrilia species.

  12. A new species of Eimeria (Apicomplexa: Eimeriidae) from tri-colored bats, Perimyotis subflavus (Chiroptera: Vespertilionidae), from the Ouachitas of Arkansas.

    Science.gov (United States)

    McAllister, Chris T; Seville, R Scott; Arlen, Robert; Connior, Matthew B

    2014-10-01

    Between February 2013 and October 2013, eleven tri-colored bats, Perimyotis subflavus were collected from Marion, Polk, and Searcy counties, Arkansas, and their faeces examined for coccidian parasites. Two of eleven (18%) harboured an eimerian that we describe here as new. Oocysts of Eimeria mcdanieli sp. n. were ellipsoidal to elongate with a bi-layered wall and measured (length × width, L × W) 28.3 × 17.9 μm, with an L/W ratio of 1.6. A micropyle and oocyst residuum were absent but a single polar granule was present. Sporocysts were ovoidal, 12.6 × 8.3 μm, with an L/W ratio of 1.5. A pronounced, nipple-like Stieda body was present as well as a substieda body. A sporocyst residuum was present as dispersed bubble-like granules. This is the third coccidian described from tri-colored bats and the sixth species reported from Arkansas chiropterans. In addition, both infected bats harbored a concurrent infection of Eimeria heidti McAllister, Burt, Seville, and Robison, 2011.

  13. Molecular phylogeny of marine gregarine parasites (Apicomplexa) from tube-forming polychaetes (Sabellariidae, Cirratulidae and Serpulidae), including descriptions of two new species of Selenidium.

    Science.gov (United States)

    Wakeman, Kevin C; Leander, Brian S

    2013-01-01

    Selenidium is a genus of gregarine parasites that infect the intestines of marine invertebrates and have morphological, ecological, and motility traits inferred to reflect the early evolutionary history of apicomplexans. Because the overall diversity and phylogenetic position(s) of these species remain poorly understood, we performed a species discovery survey of Selenidium from tube-forming polychaetes. This survey uncovered five different morphotypes of trophozoites (feeding stages) living within the intestines of three different polychaete hosts. We acquired small subunit (SSU) rDNA sequences from single-cell (trophozoite) isolates, representing all five morphotypes that were also imaged with light and scanning electron microscopy. The combination of molecular, ecological, and morphological data provided evidence for four novel species of Selenidium, two of which were established in this study: Selenidium neosabellariae n. sp. and Selenidium sensimae n. sp. The trophozoites of these species differed from one another in the overall shape of the cell, the specific shape of the posterior end, the number and form of longitudinal striations, the presence/absence of transverse striations, and the position and shape of the nucleus. A fifth morphotype of Selenidium, isolated from the tube worm Dodecaceria concharum, was inferred to have been previously described as Selenidium cf. echinatum, based on general trophozoite morphology and host association. Phylogenetic analyses of the SSU rDNA sequences resulted in a robust clade of Selenidium species collected from tube-forming polychaetes, consisting of the two new species, the two additional morphotypes, S. cf. echinatum, and four previously described species (Selenidium serpulae, Selenidium boccardiellae, Selenidium idanthyrsae, and Selenidium cf. mesnili). Genetic distances between the SSU rDNA sequences in this clade distinguished closely related and potential cryptic species of Selenidium that were otherwise very similar in trophozoite morphology.

  14. New host and distributional records for Cryptosporidium sp. (Apicomplexa: Cryptosporidiidae) from lizards (Sauria: Gekkonidae, Scincidae) from the Cook Islands and Vanuatu, South Pacific

    Science.gov (United States)

    McAllister, Chris T.; Duszynski, Donald W.; Fisher, Robert N.

    2013-01-01

    Between 1991 and 1993, 295 lizards, comprising 21 species in 2 families (Gekkonidae, Scincidae) from the Cook Islands, Fiji, Palau, Takapoto, and Vanuatu in the South Pacific, were examined for Cryptosporidium oocysts. Only 6 lizards (2%) were found to be passing Cryptosporidium oocysts in their feces, including 2 of 30 (7%) Oceania geckos, Gehyra oceanica, from Rarotonga, Cook Islands, and 4 of 26 (15%) Pacific blue-tailed skinks, Emoia caeruleocauda, from Efate Island, Vanuatu. This represents the largest survey for Cryptosporidium in Pacific island lizards, and we document 2 new host and 2 new locality records for this parasite genus.

  15. Sarcocystis masoni, n. sp. (Apicomplexa: Sarcocystidae), and redescription of Sarcocystis aucheniae from llama (Lama glama), guanaco (Lama guanicoe) and alpaca (Vicugna pacos).

    Science.gov (United States)

    Moré, Gastón; Regensburger, Cristian; Gos, M Laura; Pardini, Lais; Verma, Shiv K; Ctibor, Juliana; Serrano-Martínez, Marcos Enrique; Dubey, Jitender P; Venturini, M Cecilia

    2016-04-01

    There is considerable confusion concerning the species of Sarcocystis in South American camelids (SAC). Several species names have been used; however, proper descriptions are lacking. In the present paper, we redescribe the macroscopic sarcocyst forming Sarcocystis aucheniae and describe and propose a new name, Sarcocystis masoni for the microscopic sarcocyst forming species. Muscles samples were obtained from llamas (Lama glama) and guanacos (Lama guanicoe) from Argentina and from alpacas (Vicugna pacos) and llamas from Peru. Individual sarcocysts were processed by optical and electron microscopy, and molecular studies. Microscopic sarcocysts of S. masoni were up to 800 µm long and 35-95 µm wide, the sarcocyst wall was 2·5-3·5 µm thick, and had conical to cylindrical villar protrusions (vp) with several microtubules. Each vp had 11 or more rows of knob-like projections. Seven 18S rRNA gene sequences obtained from sarcocysts revealed 95-96% identity with other Sarcocystis spp. sequences reported in the GenBank. Sarcocysts of S. aucheniae were macroscopic, up to 1·2 cm long and surrounded by a dense and laminar 50 µm thick secondary cyst wall. The sarcocyst wall was up to 10 µm thick, and had branched vp, appearing like cauliflower. Comparison of the 11 sequences obtained from individual macroscopic cysts evidenced a 98-99% of sequence homology with other S. aucheniae sequences. In conclusion, 2 morphologically and molecularly different Sarcocystis species, S. masoni (microscopic cysts) and S. aucheniae (macroscopic cysts), were identified affecting different SAC from Argentina and Peru.

  16. Plasmodium kentropyxi n.sp. (Apicomplexa: Haemosporina: Plasmodiidae and a Plasmodium tropiduri-like parasite in the lizard Kentropyx calcarata (Lacertilia: Teiidae in North Brazil

    Directory of Open Access Journals (Sweden)

    Lainson R.

    2001-06-01

    Full Text Available Plasmodium kentropyxi n.sp. is described in the teiid lizard Kentropyx calcarata from north Brazil. Young asexual stages and gametocytes are at first polar in the erythrocyte but with elongation, move to a lateral position. Largest meronts seen contained from 30-40 nuclei and conspicuous greenish-black pigment granules located in a distinct vacuole. With growth the gametocytes eventually assume a smooth, curved cylindrical shape, with evenly rounded ends. Pigment is scattered or concentrated around a conspicuous vacuole which is slowly developed as the gametocytes mature. Mature male parasites measured 11.8 x 4.0 μm (9.6 x 4.2 - 13.2 x 3.6 μm, shape-index 2.9 (2.2 - 5.0, and females 13.5 x 4.5 μm (12.0 x 4.5 - 15.0 x 4.8 μm, shape-index 3.0 (2.2 - 3.8. Some larger meronts may slightly enlarge the erythrocyte, but most asexual stages and the mature gametocytes rarely do so. A second, P. tropiduri-like parasite encountered in K. calcarata possessed small rounded or fan-shaped meronts producing from 4-14 merozoites, and spherical to subspherical gametocytes of approximately 6.0 x 5.0 μm. The parasite was consistently polar in its position in the erythrocyte.

  17. Plasmodium kentropyxi n.sp. (Apicomplexa: Haemosporina: Plasmodiidae) and a Plasmodium tropiduri-like parasite in the lizard Kentropyx calcarata (Lacertilia: Teiidae) in north Brazil.

    Science.gov (United States)

    Lainson, R; Landau, I; Paperna, I

    2001-06-01

    Plasmodium kentropyxi n.sp. is described in the teiid lizard Kentropyx calcarata from north Brazil. Young asexual stages and gametocytes are at first polar in the erythrocyte but with elongation, move to a lateral position. Largest meronts seen contained from 30-40 nuclei and conspicuous greenish-black pigment granules located in a distinct vacuole. With growth the gametocytes eventually assume a smooth, curved cylindrical shape, with evenly rounded ends. Pigment is scattered or concentrated around a conspicuous vacuole which is slowly developed as the gametocytes mature. Mature male parasites measured 11.8 x 4.0 microns (9.6 x 4.2 - 13.2 x 3.6 microns), shape-index 2.9 (2.2 - 5.0), and females 13.5 x 4.5 microns (12.0 x 4.5 - 15.0 x 4.8 microns), shape-index 3.0 (2.2 - 3.8). Some larger meronts may slightly enlarge the erythrocyte, but most asexual stages and the mature gametocytes rarely do so. A second, P. tropiduri-like parasite encountered in K. calcarata possessed small rounded or fan-shaped meronts producing from 4-14 merozoites, and spherical to subspherical gametocytes of approximately 6.0 x 5.0 microns. The parasite was consistently polar in its position in the erythrocyte.

  18. Intestinal coccidia (Apicomplexa: Eimeriidae) of Brazilian lizards. Eimeria carmelinoi n.sp., from Kentropyx calcarata and Acroeimeria paraensis n.sp. from Cnemidophorus lemniscatus lemniscatus (Lacertilia: Teiidae).

    Science.gov (United States)

    Lainson, Ralph

    2002-03-01

    Eimeria carmelinoi n.sp., is described in the teiid lizard Kentropyx calcarata Spix, 1825 from north Brazil. Oocysts subspherical to spherical, averaging 21.25 x 20.15 micro m. Oocyst wall smooth, colourless and devoid of striae or micropyle. No polar body or conspicuous oocystic residuum, but frequently a small number of fine granules in Brownian movement. Sporocysts, averaging 10.1 x 9 microm, are without a Stieda body. Endogenous stages characteristic of the genus: intra-cytoplasmic, within the epithelial cells of the ileum and above the host cell nucleus. A re-description is given of a parasite previously described as Eimeria cnemidophori, in the teiid lizard Cnemidophorus lemniscatus lemniscatus. A study of the endogenous stages in the ileum necessitates renaming this coccidian as Acroeimeria cnemidophori (Carini, 1941) nov.comb., and suggests that Acroeimeria pintoi Lainson & Paperna, 1999 in the teiid Ameiva ameiva is a synonym of A. cnemidophori. A further intestinal coccidian, Acroeimeria paraensis n.sp. is described in C. l. lemniscatus, frequently as a mixed infection with A. cnemidophori. Mature oocysts, averaging 24.4 x 21.8 microm, have a single-layered, smooth, colourless wall with no micropyle or striae. No polar body, but the frequent presence of a small number of fine granules exhibiting Brownian movements. Sporocysts 9 x 8, without a Stieda body. Endogenous stages epicytoplasmic, characteristic of the genus, in the upper ileum. The importance of a study of the endogenous stages of eimeriid coccidia is discussed.

  19. First molecular characterization of a Hepatozoon species (Apicomplexa: Hepatozoidae) infecting birds and description of a new species infecting storm petrels (Aves: Hydrobatidae).

    Science.gov (United States)

    Merino, Santiago; Martínez, Javier; Masello, Juan F; Bedolla, Yuliana; Quillfeldt, Petra

    2014-06-01

    During a survey of blood parasites in a population of Leach's and black storm petrels ( Oceanodroma leucorhoa and Oceanodroma melania) in Mexico, infection by a Hepatozoon species in erythrocytes of several birds was noted. Here we describe the species as Hepatozoon peircei sp. nov. Some species of Hepatozoon described from birds have been identified as lankesterellids when DNA molecular analyses were conducted. However, a sequence of 1,774 bp of the parasite found infecting storm petrels in this study clearly show the parasite is a species of the genus Hepatozoon. This is the first Hepatozoon species infecting birds to be characterized at the molecular level and the first found infecting erythrocytes and not leucocytes.

  20. Numerical and functional responses to the presence of a competitor--the case of Aggregata sp. (Apicomplexa: Aggregatidae) and Octopicola superba (Copepoda: Octopicolidae).

    Science.gov (United States)

    Cavaleiro, F I; Santos, M J

    2014-02-01

    Evidence of interference competition between the eimeriorin coccidian Aggregata sp. and the octopicolid copepod Octopicola superba at the level of the gills of naturally infected Octopus vulgaris is evaluated. Numerical and functional responses are considered for analysis, and the fundamental and realized spatial niches (FSNs and RSNs) are measured as part of the study. While it was not possible to measure the FSN of Aggregata sp., the analysis of the infection levels of O. superba recorded for non-concomitantly and concomitantly infected hosts suggests that the gills and body skin constitute, respectively, the main and accessory sites of infection of the parasite. According to the evidence found, the gills function mainly as an accessory site of infection of Aggregata sp., in specimens in which the caecum and intestine are massively infected. Evidence for a negative interaction between Aggregata sp. and O. superba has been found while controlling for a potential confounding effect of host size. Furthermore, the presence of O. superba on gill lamellae appears to have been negatively affected by the presence of Aggregata sp., while this latter remained mostly undisturbed. The mean number of oocysts of Aggregata sp. in the gills was higher in spring and summer, which were also the seasons presenting the broadest RSN for O. superba.

  1. Morphological and molecular characterisation of Haemogregarina sp. (Apicomplexa: Adeleina: Haemogregarinidae) from the blood of the Caspian freshwater turtle Mauremys caspica (Gmelin) (Geoemydidae) in Iran.

    Science.gov (United States)

    Rakhshandehroo, Ehsan; Sharifiyazdi, Hassan; Ahmadi, Amin

    2016-06-01

    To date, a number of species of Haemogregarina have been described from different turtle hosts, mainly based on the morphology of the developmental stages detected in the host erythrocytes. The diversity and overlapping morphological features in the old and recent descriptions has led to considerable complications in the taxonomy of Haemogregarina spp. In this study, different stages of maturity and developing gamonts of a putative new species of Haemogregarina were detected in erythrocytes of the Caspian turtle Mauremys caspica (Gmelin) (Geoemydidae) originating from a southern province in Iran. Although some of the morphological characteristics were consistent with Haemogregarina stepanowi Danilewsky, 1885, some new observations were made, particularly in the gamont stage. The phylogenetic analysis based on 18S rDNA sequences revealed that the present isolate appears as basal to a large clade of Haemogregarina spp. with sequences available in the GenBank database. In accordance with the phylogenetic results, the present Iranian isolate showed a higher degree of interspecific divergence (up to 3.3%) compared to the data for the taxa available in the GenBank database. Thus, molecular data indicate that this isolate may represent a new species. However, further genetic analyses are needed as a complementary tool to the morphological characterisation in order to elucidate the phylogenetic relationships of Haemogregarina spp.

  2. The Genus Cyclospora (Apicomplexa: Eimeriidae, with a description of Cyclospora schneideri n.sp. in the snake Anilius scytale scytale (Aniliidae from Amazonian Brazil: a review

    Directory of Open Access Journals (Sweden)

    Ralph Lainson

    2005-04-01

    Full Text Available A review is made of the recorded species of the coccidian genus Cyclospora and major events leading up to the discovery of C. cayetanensis, which is responsible for serious outbreaks of diarrhoea in man and is one of the aetiological agents of "traveller's diarrhoea". Humans appear to be the specific hosts, with the entire life-cycle in the intestine: to date there is no convincing evidence that the disease is a zoonosis. A description is given of oocysts and endogenous stages of C. schneideri n.sp., in the snake Anilius scytale scytale. Sporulation is exogenous and completed after about one week at 24-26º. Mature oocysts 19.8 × 16.6 (15.1 × 13.8-25.7 × 20.1, shape-index 1.2 (1.0-1.3: no oocyst residuum or polar bodies. Oocyst wall a single colourless, smooth layer with no micropyle: it is rapidly deformed or broken. Sporocysts 13.6 × 9.4 (11.3 × 8.3-15.1 × 9.9, shape-index 1.4 (1.2-1.5 with an inconspicuous Stieda body. Sporozoites 11-13 × 2.5-3. Endogenous stages are intracytoplasmic in the epithelial cells of the small intestine and with the characters of the Eimeriorina.

  3. Third lineage of rodent eimerians: morphology, phylogeny and re-description of Eimeria myoxi (Apicomplexa: Eimeriidae) from Eliomys quercinus (Rodentia: Gliridae).

    Science.gov (United States)

    Kvičerová, Jana; Mikeš, Václav; Hypša, Václav

    2011-09-01

    Coccidian oocysts from feces of 46 individuals of the garden dormouse, Eliomys quercinus (Rodentia: Gliridae), were morphologically and molecularly characterized. Both morphological and sequence data (18S rDNA and ORF 470) showed low variability, indicating that all samples represent a single species. By comparison with published morphological descriptions of coccidia from glirid rodents, we determined that the samples represent Eimeria myoxi. Molecular data suggest that this species does not fall within the 2 known rodent-specific groups but branches as a third independent lineage. However, its exact position in respect to other eimerian clusters could not be established due to the lack of phylogenetic information at this taxonomic level for the 18S rRNA and ORF 470 genes. Based on these results, we provide a re-description of Eimeria myoxi, which contains morphological and molecular characteristics sufficient for its further unequivocal identification.

  4. Six new species of coccidia (Apicomplexa: Eimeriidae) from endangered Phelsuma spp. geckoes (Sauria: Gekkonidae) of the Black River Gorges National Park, Mauritius.

    Science.gov (United States)

    Daszak, Peter; Ball, Stanley J; Jones, Carl G; Streicker, Daniel G; Snow, Keith R

    2009-12-01

    Six new species of coccidia are described from endangered Phelsuma spp. geckoes (Sauria: Gekkonidae) endemic to Mauritius, Indian Ocean. Five new species (3 Eimeria and 2 Isospora species) are described from Phelsuma rosagularis Vinson et Vinson; all lack a micropyle and an oocyst residuum, and all have a sporocyst residuum. Oocysts of Eimeria swinnertonae sp. n. are ellipsoidal, 22.2 x 17.8 (20.8-24.8 x 16.8-18.4) microm; SI 1.25; polar granule absent. Sporocysts are ellipsoidal, 8.8 x 7.0 (8.0-9.6 x 6.4-8.0) microm; SI 1.3; Stieda body absent. Oocysts of Eimeria stebbinsi sp. n. are ellipsoidal, 17.4 x 11.7 (16.0-19.2 x 11.2-12.8) microm; SI 1.5; polar granules present. Sporocysts are elongate-ellipsoidal, 7.7 x 4.0 (7.2-8.0 x 3.2-5.6) microm; SI 1.9; Stieda body present. Oocysts of Eimeria raleighi sp. n. are spheroidal to sub-spheroidal, 17.0 x 15.5 (16.0-19.2 x 14.4-16.8) microm; SI 1.1; polar granule present. Sporocysts are sub-spheroidal, 7.8 x 6.6 (7.2-8.0 x 6.4-7.2) microm; SI 1.2; Stieda body absent. Oocysts of Isospora cottinghamae sp. n. are ellipsoidal, 19.8 x 15.5 (17.6-21.6 x 14.4-17.6) microm; SI 1.3; polar granules present. Sporocysts are ellipsoidal, 10.8 x 6.9 (9.6-12.8 x 6.4-8.0) microm; SI 1.6; Stieda body present. Oocysts of Isosporapearlae sp. n. are ellipsoidal, 16.0 x 11.5 (15.2-17.6 x 9.6-12.8) microm; SI 1.4; polar granule present. Sporocysts are ellipsoidal, 8.8 x 5.4 (8.0-9.6 x 4.8-6.4) microm; SI 1.6; Stieda and substieda bodies present. One new Eimeria species is described from the blue-tailed day gecko, Phelsuma cepediana Merrem. Oocysts of Eimeria hartleyi sp. n. are sub-spheroidal to ellipsoidal, 18.2 x 14.5 (16.0-20.8 x 13.6-16.0) microm; SI 1.26; polar granules present. Sporocysts are ellipsoidal to cylindroidal, 7.5 x 5.3 (6.4-8.0 x 4.8-6.4) microm; SI 1.4; Stieda body present. We report the presence of tetrazoic spheroidal to sub-spheroidal oocysts or sporocysts 10.2 x 8.5 (9.9-10.4 x 8.3-8.8) microm; SI 1.2 from an individual of P. cepediana. These oocysts or sporocysts are significantly larger than the Cryptosporidium species so far described from reptiles, and likely represent excretion of spuriously ingested sporocysts of a Sarcocystis or Adelina coccidian.

  5. Ultrastructure of developmental stages of Hemolivia mariae (Apicomplexa: Haemogregarinidae), natural parasite of the Australian sleepy lizard, in experimentally infected deviant hosts.

    Science.gov (United States)

    Paperna, I; Smallridge, C J

    2001-01-01

    Mabuya vitatta (Olivier) (Scincidae) and Agama stellio (L.) (Agamidae) were infected with Hemolivia mariae Smallridge et Paperna, 1997 by ingestion of tick viscera from Amblyomma limbatum Neumann, fed as nymphs on naturally infected Australian sleepy lizards, Tiliqua rugosa Gray. The unnatural infection apparently interfered with the developmental schedule of the parasites. Transmission electron microscopic images of merogonic stages were obtained, as well as images of early developing gametocytes. Tissue and intraerythrocytic meronts were bound by a hardened wall. Intraerythrocytic gametocytes were lodged in a parasitophorous vacuole, which was filled with granular material, and were bound by a two-membrane wall. Small and large osmiophilic bodies were located in a sub-pellicular position. With differentiation, the wall membranes tightened with the parasitophorous vacuole wall, and the osmiophilic bodies disappeared. The outer parasite membrane consolidated into a thick encasing with distinct sutures. Late infection in A. stellio comprised gametocytes only.

  6. Redescription of Haemogregarina garnhami (Apicomplexa: Adeleorina) from the blood of Psammophis schokari (Serpentes: Colubridae) as Hepatozoon garnhami n. comb. based on molecular, morphometric and morphologic characters.

    Science.gov (United States)

    Abdel-Baki, Abdel-Azeem S; Al-Quraishy, Saleh; Zhang, J Y

    2014-06-01

    Hepatozoon garnhami n. comb. was redescribed from Schokari sand snakes (Psammophis schokari) collected from Riyadh city in Saudi Arabia. Gametocytes were found in the peripheral blood of 2 of 15 snakes examined. Based on the similar morphological and morphometric characteristics, the same host and a similar host habitat environment, it can be concluded for the first time that the present species is conspecific with Haemogregarina garnhami previously reported from Psammophis shokari aegyptius. To further characterize this parasite, the partial 18S rRNA gene was amplified and sequenced. The sequence analysis also showed that Haemogregarina garnhami should be reassigned into the genus Hepatozoon as Hepatozoon garnhami which has 99.5% (859/863 bp) sequence similarity to Hepatozoon ayorgbor, infecting the erythrocytes of Python regius in Ghana. Phylogenetic analysis showed that H. garnhami formed a mixed clade with Hepatozoon spp. from geckos, snakes and rodents and ophidian Hepatozoon spp. did not form a separated phylogenetic unit. Also, Psammophis schokari-infecting Hepatozoon contained several different genetic lineages. To our knowledge, the present work extends the geographic distribution of H. garnhami and is the first report of Hepatozoon infection in snakes from Saudi Arabia.

  7. Four New Species of Eimeria (Apicomplexa: Eimeriidae) from Emoia spp. Skinks (Sauria: Scincidae), from Papua New Guinea and the Insular Pacific.

    Science.gov (United States)

    McAllister, Chris T; Duszynski, Donald W; Austin, Christopher C; Fisher, Robert N

    2017-02-01

    Between September and November 1991, 54 adult skinks from 15 species were collected by hand or blowpipe from several localities on Rarotonga, Cook Islands, Ovalau Island, Fiji, and Papua New Guinea (PNG), and their feces were examined for coccidians. Species included 5 seaside skinks (Emoia atrocostata), 1 Pacific blue-tailed skink (Emoia caeroleocauda), 2 Fiji slender treeskinks (Emoia concolor), 15 white-bellied copper-striped skinks (Emoia cyanura), 1 Bulolo River forest skink (Emoia guttata), 6 dark-bellied copper-striped skinks (Emoia impar), 5 Papua five-striped skinks (Emoia jakati), 2 Papua slender treeskinks (Emoia kordoana), 3 Papua robust treeskinks (Emoia longicauda), 1 brown-backed forest skink (Emoia loveridgei), 3 Papua black-sided skinks (Emoia pallidiceps), 2 Papua white-spotted skinks (Emoia physicae), 2 Papua yellow-head skinks (Emoia popei), 1 Papua brown forest skink (Emoia submetallica), and 5 Fiji barred treeskinks (Emoia trossula) Species of Eimeria (Ei.) were detected from these Emoia (Em.) spp. and are described here as new. Oocysts of Eimeria iovai n. sp. from Em. pallidiceps from PNG were ellipsoidal with a bilayered wall (L × W) 26.5 × 18.1 μm, with a length/width ratio (L/W) of 1.1. Both micropyle and oocyst residuum were absent, but a fragmented polar granule was present. This eimerian also was found in Em. atrocostata from PNG. Oocysts of Eimeria kirkpatricki n. sp. from Em. atrocostata from PNG were ellipsoidal with a bilayered wall, 18.6 × 13.5 μm, L/W 1.4. A micropyle and oocyst residuum were absent, but a fragmented polar granule was present. This eimerian was also shared by Em. cyanura from the Cook Islands and Fiji, Em. impar from the Cook Islands, Em. loveridgei from PNG, Em. pallidiceps from PNG, Em. popei from PNG, and Em. submetallica from PNG. Oocysts of Eimeria stevejayuptoni n. sp. from Em. longicauda were subspheroidal to ellipsoidal with a bilayered wall, 18.7 × 16.6 μm, L/W 1.1. A micropyle and oocyst residuum were absent, but a fragmented polar granule was present. Oocysts of Eimeria emoia n. sp. from Em. longicauda from PNG were cylindroidal with a bilayered wall, 29.2 × 15.7 μm, L/W 1.9. A micropyle and oocyst residuum were absent, but a polar granule was present. These are the first eimerians reported from Emoia spp. and they add to our growing knowledge of the coccidian fauna of scincid lizards of the South Pacific.

  8. Seven new species of Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae) from colubrid snakes of Guatemala and a discussion of what to call ellipsoid tetrasporocystic, dizoic coccidia of reptiles.

    Science.gov (United States)

    Asmundsson, I M; Duszynski, D W; Campbell, J A

    2006-06-01

    During a survey of Guatemalan herpetofauna in the summers of 1998-2000, 29 presumed new species of Eimeria Schneider, 1875 were found, seven of which have a distinct elongate-ellipsoidal shape (L/W ratio >or= 1.7) and are described herein. Six of the seven new species are similar in oöcyst length, width and L/W ratio and sporocyst length, width and L/W ratio, lack a micropyle, oöcyst residuum, Stieda body, sub-- and parastieda bodies, have a polar granule and sporocyst residuum, and their sporocysts appear to have dehiscence sutures. The seventh is slightly smaller and has sporocysts with a Stieda body. The new species are: E. coniophanes n. sp - whose sporulated oöcysts from Coniophanes fissidens are 29.2x14.9 (27-31x13-16) microm, with sporocysts 10.0 x 7.8 microm; E. coniophis n. sp. -from Conophis lineatus are 32.0x16.5 (30-34x14-18) microm, with sporocysts 10.2 x 8.9microm; E. dryomarchoni n. sp. - from Drymarchon corais are 32.2x17.7 (31-34x17-19) microm, with sporocysts 10.7 x 8.6 microm; E. leptophis n. sp. - from Leptophis mexicanus are 29.5x17.0 (28-31x16-18) microm, with sporocysts 10.0 x 9.1 microm; E. oxybelis n. sp. - from Oxybelis aeneus are 31.8x16.5 (29-33x15-18) microm, with sporocysts 10.3 x 8.8 microm; and E. scaphiodontophis n. sp. - from Scaphiodontophis annulatus are 30.0x15.3 (28-33x14-16) microm, with sporocysts 9.9 x 7.9 microm. Sporulated oöcysts of E. siboni n. sp. from Sibon nebulata are 24.3x14.2 (21-27x13-16) microm, with sporocysts 10.0 x 7.1 microm and with a Stieda body. We conclude that until all aspects of each life-cycle are known, it is prudent at this time to name all tetrasporocystic dizoic coccidia from snakes as members of Eimeria rather than place some of them in Choleoeimeria Paperna & Landsberg, 1989.

  9. Introducción a la protozoología clínica II (Filos Apicomplexa y Microsporidia), 2010-11

    OpenAIRE

    Fresnadillo Martínez, María José; García Sánchez, Enrique; García Sánchez, José Elías

    2010-01-01

    I. Materiales de clase: UNIDAD 1: Concepto de Parasitología. Asociaciones interespecíficas. Parasitismo; UNIDAD 2: Protozoos: taxonomía, clasificación y nomenclatura; UNIDAD 3; UNIDAD 4: Filo Microspora. Generalidades. Taxonomía y clasificación. Morfología. Epidemiología. Ciclo biológico. Patogenia. Acción patógena. Diagnóstico parasitológico. Tratamiento. Prevención. II. Bibliografía. En el curso “Introducción a la Protozoología clínica II” se pretende dar una visión sencilla y profunda d...

  10. Two new species of Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae) from emerald tree skinks, Lamprolepis smaragdina (Lesson) (Sauria: Scincidae) from Papua New Guinea and the Philippines.

    Science.gov (United States)

    McAllister, Chris T; Seville, R Scott; Duszynski, Donald W; Bush, Sarah E; Fisher, Robert N; Austin, Christopher C

    2013-10-01

    Two new species of Eimeria Schneider, 1875, from emerald tree skinks, Lamprolepis smaragdina (Lesson) are described from specimens collected in Papua New Guinea (PNG) and the Philippines. Oöcysts of Eimeria nuiailan n. sp. from the only L. smaragdina from PNG are ovoidal, with a smooth, colourless, bi-layered wall, measure 23.7 × 19.1 μm, and have a length/width (L/W) ratio of 1.3; both micropyle and oöcyst residuum are absent, but a fragmented polar granule is present. Sporocysts are ovoidal to ellipsoidal, 11.9 × 7.0 μm, L/W 1.7, and the wall is composed of two valves joined by a longitudinal suture; neither Stieda nor sub-Stieda bodies are present; a sporocyst residuum is present as a compact mass of granules. Sporozoites are elongate, 14.6 × 2.6 μm, and contain anterior and posterior refractile bodies with a nucleus between them. Oöcysts of Eimeria auffenbergi n. sp. from L. smaragdina collected in the Philippines are ovoidal, with a smooth, colourless, bi-layered wall, measure 19.9 × 15.8 μm, L/W 1.3; both micropyle and oöcyst residuum are absent, but one to four polar granules are present. Sporocysts are ovoidal to ellipsoidal, 10.3 × 5.8 μm, L/W 1.8, and the wall is composed of two valves joined by a longitudinal suture; neither Stieda nor sub-Stieda bodies are present; a sporocyst residuum is composed of dispersed granules.

  11. [Babesia choloepi n. sp. (Apicomplexa, Piroplasmida), a parasite of the two-toed sloth, Choloepus didactylus (Linnaeus, 1758) (Xenarthra, Bradypodidae), in French Guiana].

    Science.gov (United States)

    Dedet, J P; Veilly, M; Robin, Y; Bonnevie, O; Landau, I

    1988-01-01

    A two-toed sloth (Choloepus didactylus) from French Guiana showed an erythrocytic parasite morphologically related to the Babesiidae family, and described as Babesia choloepi. It is the first Babesia species described in the Edentata order.

  12. Two new species of Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae) from emerald tree skinks, Lamprolepis smaragdina (Lesson) (Sauria: Scincidae) from Papua New Guinea and the Philippines

    Science.gov (United States)

    McAllister, Chris T.; Seville, R. Scott; Duszynski, Donald W.; Bush, Sarah E.; Fisher, Robert N.; Austin, Christopher C.

    2013-01-01

    Two new species of Eimeria Schneider, 1875, from emerald tree skinks, Lamprolepis smaragdina (Lesson) are described from specimens collected in Papua New Guinea (PNG) and the Philippines. Oöcysts of Eimeria nuiailan n. sp. from the only L. smaragdina from PNG are ovoidal, with a smooth, colourless, bi-layered wall, measure 23.7 × 19.1 μm, and have a length/width (L/W) ratio of 1.3; both micropyle and oöcyst residuum are absent, but a fragmented polar granule is present. Sporocysts are ovoidal to ellipsoidal, 11.9 × 7.0 μm, L/W 1.7, and the wall is composed of two valves joined by a longitudinal suture; neither Stieda nor sub-Stieda bodies are present; a sporocyst residuum is present as a compact mass of granules. Sporozoites are elongate, 14.6 × 2.6 μm, and contain anterior and posterior refractile bodies with a nucleus between them. Oöcysts of Eimeria auffenbergi n. sp. from L. smaragdina collected in the Philippines are ovoidal, with a smooth, colourless, bi-layered wall, measure 19.9 × 15.8 μm, L/W 1.3; both micropyle and oöcyst residuum are absent, but one to four polar granules are present. Sporocysts are ovoidal to ellipsoidal, 10.3 × 5.8 μm, L/W 1.8, and the wall is composed of two valves joined by a longitudinal suture; neither Stieda nor sub-Stieda bodies are present; a sporocyst residuum is composed of dispersed granules.

  13. A new species of Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae) from the Solomon ground skink, Sphenomorphus solomonis (Boulenger) (Sauria: Scincidae) from Papua New Guinea

    Science.gov (United States)

    McAllister, Chris T.; Duszynski, Donald W.; Fisher, Robert N.; Austin, Christopher C.

    2014-01-01

    Between September 1990 and November 1991, 19 Sphenomorphus spp. skinks, including nine S. jobiense, three S. simus, and seven Solomon ground skinks, S. solomonis (Boulenger), were collected from Madang and Morobe Provinces, Papua New Guinea (PNG), and examined for coccidia. A single S. solomonis was found to be infected with a new species of Eimeria Schneider, 1875. Oöcysts of Eimeria perkinsae n. sp. are ellipsoidal with a smooth, colourless, bi-layered wall, measure 18.6 × 14.7 μm, and have a length/width (L/W) ratio of 1.3; both micropyle and oöcyst residuum are absent, but a fragmented polar granule is present. Sporocysts are ovoidal, 8.9 × 6.4 μm, L/W 1.4; neither Stieda, sub-Stieda or para-Stieda bodies are present; a sporocyst residuum consisted of a loose cluster of granules dispersed between sporozoites. Sporozoites are comma-shaped with spheroidal anterior and posterior refractile bodies. This represents the first report of coccidia from this skink genus.

  14. Oocyst shedding by green-winged-saltator (Saltator similis in the diagnostic of coccidiosis and Isospora similisi n. sp. (Apicomplexa: Eimeriidae Eliminação de oocistos por trinca-ferro-verdadeiro (Saltator similis no diagnóstico da coccidiose e Isospora similisi n. sp. (Apicomplexa: Eimeriidae

    Directory of Open Access Journals (Sweden)

    Cleide Domingues Coelho

    2013-03-01

    Full Text Available Diurnal periodicity is a phenomenon that has been observed in coccidian of Isospora parasites of passerines, which have been eliminated great number of oocysts at dusk. The objective of this study was to evaluate the occurrence of periodicity of oocysts presence in the green-winged-saltator Saltator similis, and its use in the diagnosis of coccidiosis in wild birds in captivity. A total of 220 fecal samples were collected from birds, apprehended from illegal trading and kept in quarantine in CETAS∕IBAMA, in the morning and late afternoon, from May to November 2010. It was observed that 1.82% of the samples collected in the morning were positive, while 31.36% of samples were positive in the late afternoon. In addition, the number of oocysts shed was greater in the afternoon. Therefore, it was concluded that the sampling in the late afternoon provided greater reliability for the diagnosis of coccidiosis in green-winged-saltators. Moreover, in this study a new isosporoid coccidian parasite from the green-winged-saltator S. similis was observed and is herein described. Isospora similisi n. sp. oocysts are spheroidal to sub-spheroidal, 27.5 × 25.9 µm, with a smooth and bi-layered wall, ∼1.2 mm. Micropyle and oocyst residuum are absent, but splinter-like or comma-like granules are present. Sporocysts are ellipsoidal or slightly ovoidal, 17.4 × 12.2 mm. A stieda body and substieda body are present. The sporocyst residuum is composed of granules of different sizes. Sporozoites are vermiform with a single refractile body and a nucleus. This is the fourth description of an isosporoid coccidium infecting S. similis and the sixth description from Cardinalidae.A periodicidade diurna é um fenômeno que tem sido observado em coccídios do gênero Isospora parasitas de pássaros, os quais eliminam uma maior quantidade de oocistos ao entardecer. O objetivo deste estudo foi determinar a periodicidade de eliminação de oocistos pelas fezes no trinca-ferro-verdadeiro Saltator similis, e sua utilização no diagnóstico da coccidiose. Foram colhidas 220 amostras fecais de aves oriundas de apreensões do tráfico de animais silvestres e mantidas na quarentena do CETAS∕IBAMA, nos períodos da manhã e ao entardecer, de maio a novembro de 2010. Observou-se que 1,82% das amostras colhidas no período da manhã foram positivas, enquanto que 31,36% das amostras colhidas foram positivas ao entardecer, onde o maior número de oocistos foi observado no período da tarde. Portanto, concluiu-se que a colheita de amostras ao entardecer oferece maior confiabilidade para o diagnóstico da coccidiose. Além disso, descreve-se um novo coccídio do trinca-ferro-verdadeiro S. similis. Isospora similisi n. sp. possui oocistos esféricos a subesféricos, 27,5 × 25,9 µm, com parede dupla e lisa, ∼1,2 µm. A micrópila e o resíduo do oocisto estão ausentes, porém pequenos grânulos estão presentes. Os esporocistos são elipsóides ou levemente ovóides, 17,4 × 12,2 µm. Os corpos de Stieda e substieda estão presentes. O resíduo do esporocisto está presente e os esporozoítos possuem um corpo refrátil posterior e um núcleo. Esta é a quarta espécie isosporóide descrita de S. similis e a sexta descrição na família Cardinalidae.

  15. Description of Eimeria motelo sp. n. (Apicomplexa: Eimeriidae from the yellow footed tortoise, Geochelone denticulata (Chelonia: Testudinidae, and replacement of Eimeria carinii Lainson, Costa & Shaw, 1990 by Eimeria lainsoni nom. nov.

    Directory of Open Access Journals (Sweden)

    Lada Hurková

    2000-12-01

    Full Text Available Eimeria motelo sp. n. is described from faeces of the yellow-footed tortoise, Geochelone denticulata (L.. Oocysts are irregularly ellipsoidal or cylindrical, with slightly expressed lobed protrusions and irregularities at the poles, possibly caused by wrinkling of the oocyst wall, 17 (15-19 × 9.4 (8.5-11 µm, shape index (length/width being 1.81 (1.45-2. The oocyst wall is smooth, single-layered, 0.5 µm thick with no micropyle. There are no polar bodies. Sporocysts are ellipsoidal, 8.9 (7.5-10 × 4.4 (4-5 µm, shape index 2.03 (1.7-2.5. A sporocyst residuum is present, composed of many granules of irregular size. The sporozoites are elongate, lying lengthwise in the sporocysts. Comparison with other species of the genus Eimeria parasitising members of family Testudinidae indicates that the presently described coccidium represents a new species. The name of Eimeria carinii Lainson, Costa & Shaw, 1990 is found to be preoccupied by a homonym, Eimeria carinii Pinto 1928 given to a coccidium from Rattus norvegicus. Therefore, it is replaced by Eimeria lainsoni nom. nov.

  16. Endogenous development, pathogenicity and host specificity of Eimeria cahirinensis Couch, Blaustein, Duszynski, Shenbrot and Nevo, 1997 (Apicomplexa: Eimeriidae) from Acomys dimidiatus (Cretzschmar 1826) (Rodentia: Muridae) from the Near East.

    Science.gov (United States)

    Kvicerová, Jana; Ptácková, Pavla; Modrý, David

    2007-01-01

    Eimeria cahirinensis Couch et al. 1997 was found in faecal samples of Acomys dimidiatus from three different localities in the Near East. Twenty-two of 104 (21%) A. dimidiatus trapped on both the south- and north-facing slopes of "Evolution Canyon", Lower Nahal Oren, Mt. Carmel, Israel in August 2001 and 2002 were infected with E. cahirinensis. Oocysts were also obtained from a single individual of A. dimidiatus trapped in Wadi Ramm, Jordan in the summer of 1999. Laboratory-reared spiny mice (Acomys spp.) were inoculated to determine the prepatent and patent period, sporulation time, site of infection, immunogenicity, pathogenicity, pathology and morphology of endogenous stages of E. cahirinensis. Both asexual and sexual stages were localised in the apical part of duodenal and jejunal villi. An experimental inoculation of representatives of several rodent genera revealed the host range of E. cahirinensis to be limited to the genus Acomys.

  17. Isospora coerebae n. sp. (Apicomplexa: Eimeriidae from the bananaquit Coereba flaveola (Passeriformes: Coerebidae in South America Isospora coerebae n. sp. do caga-sebo Coereba flaveola (Passeriformes: Coerebidae na América do Sul

    Directory of Open Access Journals (Sweden)

    Bruno Pereira Berto

    2011-03-01

    Full Text Available The present study describes a new isosporoid coccidian parasite from the bananaquit Coereba flaveola, in Brazil. This new species is similar to I. cagasebi, but it can be distinguished by the size and shape of Stieda and susbstieda bodies. Isospora coerebae n. sp. oocysts are spheroidal to sub-spheroidal, 24.8 × 23.3 µm, with a smooth and bi-layered wall, ~1.2 µm. Micropyle, oocyst residuum and polar granule are absent. Sporocysts are elongate ovoidal, 17.9 × 10.9 µm. Stieda and substieda bodies are present. Sporocyst residuum is present and sporozoites have a posterior refractile body.Um novo parasito coccídio isosporóide do caga-sebo Coereba flaveola, do Brasil, é relatado no estudo atual. Essa nova espécie é semelhante à Isospora cagasebi, no entanto, pode ser distinguida pelos tamanho e forma dos corpos de Stieda e substieda. Os oocistos de I. coerebae n. sp. são esféricos a subesféricos, 24,8 × 23,3 µm, com parede dupla e lisa, ~ 1,2 µm. A micrópila, resíduo e grânulo polar do oocisto estão ausentes. Os esporocistos são ovóides alongados, 17,9 × 10,9 µm. Os corpos de Stieda e substieda estão presentes. O resíduo do esporocisto está presente e os esporozoítos possuem um corpo refrátil posterior.

  18. [Occurrence of Cryptosporidium spp. oocysts (Apicomplexa, Cryptosporidiidae) in ostriches, Struthio camelus L., 1758 (Aves, Struthionidae) reared in North and Lowered Coastline regions of the state of Rio de Janeiro, Brazil].

    Science.gov (United States)

    Oliveira, Francisco Carlos R; Ederli, Nicole B; Ederli, Bianca B; Albuquerque, Marcia C; Dos Santos, Michelle Daniele

    2008-09-01

    The aim of this research was to determine the prevalence of Cryptosporidium spp. in ostriches reared in the state of Rio de Janeiro. The diagnosis of oocysts of Cryptosporidium spp. in the feces of 77 ostriches was done by modified Ziehl-Neelsen technique. The occurrence was observed in 44.4% of the examined animals. However, in a property 100% of the ostriches shed oocysts in their feces. Oocysts was subspherical in shape with 6.33 +/- 1.27 (4.31-9.63) by 5.90 +/- 1.18 (4.07-9.42) mm and shape index of 1.07 +/- 0.05 (1.00-1.29). Was verified a high occurrence of oocysts elimination. In spite was observed a uniform distribution of the oocysts measurements in the regression line (R2 = 0.9438) accentuated difference was evidenced in the morphometry of the oocysts, that suggests that more of a species of Cryptosporidium are parasitizing these birds.

  19. Présence de trois espèces de grégarines (Apicomplexa : Eugregarinorida chez l’Annélide Polychete Marphysa sanguinea (Montagu, 1815 dans le lac de Tunis

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    Elbarhoumi M.

    2010-03-01

    Full Text Available Trois espèces de grégarines ont été trouvées dans des spécimens de l’annélide polychète Marphysa sanguinea récoltés dans le lac de Tunis : Bhatiella marphysae Setna, 1931, parasite de Marphysa sanguinea (Inde, Europe; Ferraria cornucephala iwamusi H. Hoshide, 1956, parasite de Marphysa iwamusi (Japon ; et Viviera sp. qui présente des similitudes avec Viviera marphysae Schrével, 1963, aussi décrite chez Marphysa sanguinea (France. Ces grégarines sont rapportées pour la première fois chez ce dernier hôte en Tunisie. Bhatiella marphysae et Viviera sp. appartiennent à la famille des Lecudinidae (Aseptatorina. La présence d’un septum proto-deutoméritique est confirmée chez Ferraria cornucephala qui doit être maintenue dans les Polyrhabdinae.

  20. 顶复门原虫类异戊二烯生物合成途径及其关键酶的研究进展%Advance in Isoprenoids Biosynthesis Pathway and DOXP Reductoisomerase in Apicomplexa

    Institute of Scientific and Technical Information of China (English)

    廖申权; 吴彩艳; 戚南山; 吕敏娜; 覃宗华; 孙铭飞

    2012-01-01

    顶复门原虫包括疟原虫(Plasmodium spp.)、刚地弓形虫(Toxoplasma gondii)、艾美耳球虫(Eimeria spp.)、锥虫(Trypanosoma spp.)、泰勒虫(Theileria spp.)及巴贝斯虫(Babesia spp.)等一大类引起严重人畜疾病的寄生性原虫.顶复门原虫利用2C-甲基-D-赤藓糖醇-4-磷酸(MEP)途径合成类异戊二烯前体物质,这些化合物对于维持顶复门原虫的生存具有十分重要的作用.1-脱氧-D-木酮糖-5-磷酸(DOXP)还原异构酶是MEP途径的关键酶,对其作用机理及抑制剂的筛选研究已取得重要进展.论文对顶复门原虫类异戊二烯的MEP途径,DOXP还原异构酶的作用机理及靶标研究进展进行综述.

  1. Cystoisospora canis (Apicomplexa: Sarcocystidae): development of monozoic tissue cysts in human cells, demonstration of egress of zoites from tissue cysts, and demonstration of repeat monozoic tissue cyst formation by zoites.

    Science.gov (United States)

    Houk, Alice E; Lindsay, David S

    2013-11-01

    Sporozoites of Cystoisospora canis penetrated and developed to monozoic tissue cysts in 4 human, 1 monkey, 1 bovine and 2 canine cell lines. No asexual division was documented although multiple infection of a single cell was observed. Examination of cultures using transmission electron microscopy demonstrated that they were monozoic tissue cysts and contained a single sporozoite. The appearance of monozoic tissue cysts in all cell lines was similar but the parasitophorous vacuole surrounding some sporozoites in DH82 dog macrophages was swollen. Monozoic tissue cysts were observed for up to 127 days in human pigmented retinal epithelial cells. Treatment of cell cultures containing monozoic tissue cysts with 0.75 sodium taurocholic acid and 0.25% trypsin stimulated egress of zoites (former sporozoites) from tissue cysts. Zoites collected from monozoic tissue cysts were able to penetrate and develop to monozoic tissue cysts in new host cells. Monozoic tissue cysts survived exposure to acid pepsin solution indicating that they would be orally infectious. The tissue cyst wall surrounding zoites did not autofluoresce as did oocyst and sporocyst walls exposed to UV light. We believe that C. canis can be used as a model system to study extra-intestinal monozoic tissue cysts stages of Cystoisospora belli of humans.

  2. Uso del microhábitat por el protozoo parásito Aggregata patagonica Sardella, Ré & Timi, 2000 (Apicomplexa: Aggregatidae en su hospedador definitivo, el pulpo Enteroctopus megalocyathus (Gould, 1852 (Cephalopoda: Octopodidae en el sur de Chile Microhabitat use by the protozoan parasite Aggregata patagonica Sardella, Ré & Timi, 2000 (Apicomplexa: Aggregatidae in his definitive host Enteroctopus megalocyathus (Gould, 1852 (Cephalopoda: Octopodidae in southern Chile

    Directory of Open Access Journals (Sweden)

    CHRISTIAN M. IBÁÑEZ

    2005-09-01

    Full Text Available Los protozoos de la familia Aggregatidae requieren de dos hospedadores para completar su ciclo biológico: un crustáceo y un cefalópodo. En este estudio se busca evidenciar si existe un uso diferencial de microhábitats de las infrapoblaciones de Aggregata patagonica entre dos zonas del tracto digestivo de su hospedador definitivo, el pulpo Enteroctopus megalocyathus. Para ello, se examinaron 40 ejemplares de Ancud y 37 de Quellón, provenientes de las capturas artesanales de la Isla de Chiloé. El tamaño y la densidad de los ooquistes se cuantificaron en el ciego y el intestino del hospedador. Además, se efectuaron observaciones histológicas para determinar cuantitativamente la ocurrencia de los distintos estados de desarrollo del parásito. En Ancud el 80 % de los pulpos estaban parasitados en el ciego y el intestino, mientras que en Quellón era el 100 %. Se determinaron cuatro estados de desarrollo (microgametos, cigotos, esporoquistes inmaduros y maduros. Los ooquistes de A. patagonica fueron más pequeños y abundantes en el ciego, pero la cobertura fue mayor en el intestino. Además, la densidad y cobertura aumenta en pocos meses entre una muestra y otra. Al parecer, A. patagonica no usaría a los dos microhábitats como lugares de preferencia para pasar los diferentes estados de desarrollo, sino más bien, y según las condiciones del microhábitat, en el intestino crecerían más los ooquistes pero en menos cantidad, ocupando una mayor superficie del microhábitat, contrario a lo que ocurre en el ciego. Por esto se sugiere que A. patagonica hace un uso diferencial del microhábitat, mediante dos estrategias distintas de historia de vidaThe protozoan parasites of the family Aggregatidae, require two hosts to complete their life cycle, a crustacean and a cephalopod. This research looks for evidence of differential microhabitat use of Aggregata patagonica infrapopulations between two zones of the digestive tract of his definitive host, the octopus Enteroctopus megalocyathus. Forty specimens from Ancud and 37 from Quellón coming from artisanal catch from Chiloé Island in southern Chile were examined. The size and density of the oocysts were quantified in the caecum and intestine of the host. Histological preparations were carried out to determine quantitatively the occurrence of the different development stages of the parasite. In Ancud, 80 % of octopuses were parasited in the caecum and intestine, while in Quellón 100 % had oocyst. Four development stages (microgametes, zygotes, immature and mature sporocysts were recognized. The oocysts of Aggregata patagonica were smaller and more abundant in the caecum, but their coverage was higher in the intestine. Moreover, density and coverage increased in few months between samples. Apparently, Aggregata patagonica does not use the two microhabitats as preferential places to pass the different developmental stages, but rather, and according to the conditions of the microhabitat, the oocysts would grow more in the intestine albeit in small number, occupying a higher surface of the microhabitat, contrary to what happens in the caecum. This suggests that A. patagonica may have two distinct life history strategies

  3. Sarcocystosis of animals and humans

    Science.gov (United States)

    Species of Sarcocystosis, single-celled protozoan parasites in the Phylum Apicomplexa, are widespread in warm-blooded animals. Completion of the life cycle requires two host species: an intermediate (or prey) host and a definitive (or predator) host. Hosts can harbor more than one species of Sarcocy...

  4. Repertoire of theileria equi antigens bound by equine antibody during persistent phase of infection

    Science.gov (United States)

    Theileriosis in horses and cattle is caused by tick-borne Apicomplexa parasites that cause death or persist for life in their respective hosts. Due to transmission risk associated with persistence, infection severely limits movement of horses and cattle between countries. The recent reemergence of T...

  5. Detection of Babesia divergens in southern Norway by using an immunofluorescence antibody test in cow sera

    OpenAIRE

    2010-01-01

    Background The incidence of bovine babesiosis, caused by Babesia divergens (Apicomplexa: Piroplasmida) has decreased markedly since the 1930 s, but may re-emerge as a consequence of climate change and changes in legislation and pasturing practices. This is a potentially serious disease, with both economical and animal welfare consequences. Therefore, there is a need to survey the distribution of B. divergens. Methods ...

  6. Comparative bioinformatics analysis of transcription factor genes suggests conservation of key regulatory domains among babesia bovis, B. microti and theileria equi.

    Science.gov (United States)

    Apicomplexa tick borne hemoparasites including B. bovis, B. microti, and Theileria equi are responsible for bovine and human babesiosis and equine theileriosis respectively. These neglected parasites of vast medical, epidemiological, and economic impact have complex life cycles in their vertebrate a...

  7. Cell fractionation of parasitic protozoa: a review

    Directory of Open Access Journals (Sweden)

    Souza Wanderley de

    2003-01-01

    Full Text Available Cell fractionation, a methodological strategy for obtaining purified organelle preparations, has been applied successfully to parasitic protozoa by a number of investigators. Here we present and discuss the work of several groups that have obtained highly purified subcellular fractions from trypanosomatids, Apicomplexa and trichomonads, and whose work have added substantially to our knowledge of the cell biology of these parasites.

  8. Sequencing of the smallest Apicomplexan genome from the human pathogen Babesia microti†

    Science.gov (United States)

    Cornillot, Emmanuel; Hadj-Kaddour, Kamel; Dassouli, Amina; Noel, Benjamin; Ranwez, Vincent; Vacherie, Benoît; Augagneur, Yoann; Brès, Virginie; Duclos, Aurelie; Randazzo, Sylvie; Carcy, Bernard; Debierre-Grockiego, Françoise; Delbecq, Stéphane; Moubri-Ménage, Karina; Shams-Eldin, Hosam; Usmani-Brown, Sahar; Bringaud, Frédéric; Wincker, Patrick; Vivarès, Christian P.; Schwarz, Ralph T.; Schetters, Theo P.; Krause, Peter J.; Gorenflot, André; Berry, Vincent; Barbe, Valérie; Ben Mamoun, Choukri

    2012-01-01

    We have sequenced the genome of the emerging human pathogen Babesia microti and compared it with that of other protozoa. B. microti has the smallest nuclear genome among all Apicomplexan parasites sequenced to date with three chromosomes encoding ∼3500 polypeptides, several of which are species specific. Genome-wide phylogenetic analyses indicate that B. microti is significantly distant from all species of Babesidae and Theileridae and defines a new clade in the phylum Apicomplexa. Furthermore, unlike all other Apicomplexa, its mitochondrial genome is circular. Genome-scale reconstruction of functional networks revealed that B. microti has the minimal metabolic requirement for intraerythrocytic protozoan parasitism. B. microti multigene families differ from those of other protozoa in both the copy number and organization. Two lateral transfer events with significant metabolic implications occurred during the evolution of this parasite. The genomic sequencing of B. microti identified several targets suitable for the development of diagnostic assays and novel therapies for human babesiosis. PMID:22833609

  9. Toxoplasma Gondii in animali da reddito e rischio per l'uomo tramite il consumo di carne

    OpenAIRE

    Condoleo, Roberto

    2016-01-01

    Toxoplasma gondii è un protozoo del phylum Apicomplexa, parassita di numerose specie animali e dell’uomo. Gli ospiti definitivi di T. gondii sono felidi domestici e selvatici, incluso il gatto domestico, i quali sono gli unici in grado di diffondere oocisti con le feci. Gli ospiti intermedi del protozoo comprendono numerose specie di mammiferi ed uccelli, incluso ovini, caprini, bovini, bufali, equini ed uomo. La toxoplasmosi è riconosciuta come una importante causa di infertilità negli ovini...

  10. Estudio retrospectivo de caracterización de la hepatozoonosis canina en Buenos Aires

    OpenAIRE

    Scodellaro, Carla Floriana

    2015-01-01

    La hepatozoonosis canina es una enfermedad parasitaria causada por protozoarios del género Hepatozoon (Apicomplexa, Eucoccida) y trasmitida por garrapatas. En Argentina, esta enfermedad fue descripta por primera vez en 1999 y recién en 2007 fue identificado Hepatozoon canis como el agente etiológico. El objetivo de este trabajo fue caracterizar la hepatozoonosis en perros del sur del Gran Buenos Aires. Para ello, se analizaron los hemogramas de 100123 muestras de sangre canina remitidas entre...

  11. Use of proteinase K in the excystation of Sarcocystis cruzi sporocysts for in vitro culture and DNA extraction.

    Science.gov (United States)

    Ndiritu, W; Cawthorn, R J; Kibenge, F S

    1994-03-01

    Proteinase K was used for the cleaning of Sarcocystis cruzi (Apicomplexa) sporocysts prior to excystation. Bovine pulmonary endothelial cell cultures inoculated with the excysted sporozoites remained free of bacterial contamination for the duration of the experiment and had high yields of merozoites. The excysted sporozoites also yielded genomic DNA that could be labelled efficiently with 32P dATP by the random priming method.

  12. Cyst wall ultrastructure of two Sarcocystis spp. from European mouflon (Ovis ammon musimon) in Germany compared with domestic sheep.

    Science.gov (United States)

    Odening, K; Stolte, M; Walter, G; Bockhardt, I

    1995-10-01

    Muscle samples from six wild and two captive European mouflons (Ovis ammon musimon) in Germany as well as one domestic sheep from a German zoo were infected with sarcocysts (Sarcocystis: Sarcocystidae, Apicomplexa). Sarcocystis tenella and S. arieticanis were identified by light and electron microscopy. Both species are determined for the first time from wild sheep, and this is the first description of S. arieticanis from wild sheep.

  13. Characterization of a Toxoplasma gondii calcium calmodulin-dependent protein kinase homolog

    OpenAIRE

    Kato, Kentaro; Sugi, Tatsuki; Takemae, Hitoshi; Takano, Ryo; Gong, Haiyan; Ishiwa, Akiko; Horimoto, Taisuke; Akashi, Hiroomi

    2016-01-01

    Background Toxoplasma gondii is an obligate intracellular parasite of the phylum Apicomplexa and a major pathogen of animals and immunocompromised humans, in whom it causes encephalitis. Understanding the mechanism of tachyzoite invasion is important for the discovery of new drug targets and may serve as a model for the study of other apicomplexan parasites. We previously showed that Plasmodium falciparum expresses a homolog of human calcium calmodulin-dependent protein kinase (CaMK) that is ...

  14. Recent advances in understanding apicomplexan parasites [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Frank Seeber

    2016-06-01

    Full Text Available Intracellular single-celled parasites belonging to the large phylum Apicomplexa are amongst the most prevalent and morbidity-causing pathogens worldwide. In this review, we highlight a few of the many recent advances in the field that helped to clarify some important aspects of their fascinating biology and interaction with their hosts. Plasmodium falciparum causes malaria, and thus the recent emergence of resistance against the currently used drug combinations based on artemisinin has been of major interest for the scientific community. It resulted in great advances in understanding the resistance mechanisms that can hopefully be translated into altered future drug regimens. Apicomplexa are also experts in host cell manipulation and immune evasion. Toxoplasma gondii and Theileria sp., besides Plasmodium sp., are species that secrete effector molecules into the host cell to reach this aim. The underlying molecular mechanisms for how these proteins are trafficked to the host cytosol (T. gondii and Plasmodium and how a secreted protein can immortalize the host cell (Theileria sp. have been illuminated recently. Moreover, how such secreted proteins affect the host innate immune responses against T. gondii and the liver stages of Plasmodium has also been unraveled at the genetic and molecular level, leading to unexpected insights. Methodological advances in metabolomics and molecular biology have been instrumental to solving some fundamental puzzles of mitochondrial carbon metabolism in Apicomplexa. Also, for the first time, the generation of stably transfected Cryptosporidium parasites was achieved, which opens up a wide variety of experimental possibilities for this understudied, important apicomplexan pathogen.

  15. Recent advances in understanding apicomplexan parasites

    Science.gov (United States)

    Seeber, Frank; Steinfelder, Svenja

    2016-01-01

    Intracellular single-celled parasites belonging to the large phylum Apicomplexa are amongst the most prevalent and morbidity-causing pathogens worldwide. In this review, we highlight a few of the many recent advances in the field that helped to clarify some important aspects of their fascinating biology and interaction with their hosts. Plasmodium falciparum causes malaria, and thus the recent emergence of resistance against the currently used drug combinations based on artemisinin has been of major interest for the scientific community. It resulted in great advances in understanding the resistance mechanisms that can hopefully be translated into altered future drug regimens. Apicomplexa are also experts in host cell manipulation and immune evasion. Toxoplasma gondii and Theileria sp., besides Plasmodium sp., are species that secrete effector molecules into the host cell to reach this aim. The underlying molecular mechanisms for how these proteins are trafficked to the host cytosol ( T. gondii and Plasmodium) and how a secreted protein can immortalize the host cell ( Theileria sp.) have been illuminated recently. Moreover, how such secreted proteins affect the host innate immune responses against T. gondii and the liver stages of Plasmodium has also been unraveled at the genetic and molecular level, leading to unexpected insights. Methodological advances in metabolomics and molecular biology have been instrumental to solving some fundamental puzzles of mitochondrial carbon metabolism in Apicomplexa. Also, for the first time, the generation of stably transfected Cryptosporidium parasites was achieved, which opens up a wide variety of experimental possibilities for this understudied, important apicomplexan pathogen. PMID:27347391

  16. In silico analysis of the cyclophilin repertoire of apicomplexan parasites

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    von Samson-Himmelstjerna Georg

    2009-06-01

    Full Text Available Abstract Background Cyclophilins (Cyps are peptidyl cis/trans isomerases implicated in diverse processes such as protein folding, signal transduction, and RNA processing. They are also candidate drug targets, in particular for the immunosuppressant cyclosporine A. In addition, cyclosporine is known to exhibit anti-parasitic effects on a wide range of organisms including several apicomplexa. In order to obtain new non-immunosuppressive drugs targeting apicomplexan cyclophilins, a profound knowledge of the cyclophilin repertoire of this phylum would be necessary. Results BLAST and maximum likelihood analyses identified 16 different cyclophilin subfamilies within the genomes of Cryptosporidium hominis, Toxoplasma gondii, Plasmodium falciparum, Theileria annulata, Theileria parva, and Babesia bovis. In addition to good statistical support from the phylogenetic analysis, these subfamilies are also confirmed by comparison of cyclophilin domain architecture. Within an individual genome, the number of different Cyp genes that could be deduced varies between 7–9 for Cryptosporidia and 14 for T. gondii. Many of the putative apicomplexan cyclophilins are predicted to be nuclear proteins, most of them presumably involved in RNA processing. Conclusion The genomes of apicomplexa harbor a cyclophilin repertoire that is at least as complex as that of most fungi. The identification of Cyp subfamilies that are specific for lower eukaryotes, apicomplexa, or even the genus Plasmodium is of particular interest since these subfamilies are not present in host cells and might therefore represent attractive drug targets.

  17. The Conoid Associated Motor MyoH Is Indispensable for Toxoplasma gondii Entry and Exit from Host Cells.

    Science.gov (United States)

    Graindorge, Arnault; Frénal, Karine; Jacot, Damien; Salamun, Julien; Marq, Jean Baptiste; Soldati-Favre, Dominique

    2016-01-01

    Many members of the phylum of Apicomplexa have adopted an obligate intracellular life style and critically depend on active invasion and egress from the infected cells to complete their lytic cycle. Toxoplasma gondii belongs to the coccidian subgroup of the Apicomplexa, and as such, the invasive tachyzoite contains an organelle termed the conoid at its extreme apex. This motile organelle consists of a unique polymer of tubulin fibres and protrudes in both gliding and invading parasites. The class XIV myosin A, which is conserved across the Apicomplexa phylum, is known to critically contribute to motility, invasion and egress from infected cells. The MyoA-glideosome is anchored to the inner membrane complex (IMC) and is assumed to translocate the components of the circular junction secreted by the micronemes and rhoptries, to the rear of the parasite. Here we comprehensively characterise the class XIV myosin H (MyoH) and its associated light chains. We show that the 3 alpha-tubulin suppressor domains, located in MyoH tail, are necessary to anchor this motor to the conoid. Despite the presence of an intact MyoA-glideosome, conditional disruption of TgMyoH severely compromises parasite motility, invasion and egress from infected cells. We demonstrate that MyoH is necessary for the translocation of the circular junction from the tip of the parasite, where secretory organelles exocytosis occurs, to the apical position where the IMC starts. This study attributes for the first time a direct function of the conoid in motility and invasion, and establishes the indispensable role of MyoH in initiating the first step of motility along this unique organelle, which is subsequently relayed by MyoA to enact effective gliding and invasion.

  18. The Conoid Associated Motor MyoH Is Indispensable for Toxoplasma gondii Entry and Exit from Host Cells.

    Directory of Open Access Journals (Sweden)

    Arnault Graindorge

    2016-01-01

    Full Text Available Many members of the phylum of Apicomplexa have adopted an obligate intracellular life style and critically depend on active invasion and egress from the infected cells to complete their lytic cycle. Toxoplasma gondii belongs to the coccidian subgroup of the Apicomplexa, and as such, the invasive tachyzoite contains an organelle termed the conoid at its extreme apex. This motile organelle consists of a unique polymer of tubulin fibres and protrudes in both gliding and invading parasites. The class XIV myosin A, which is conserved across the Apicomplexa phylum, is known to critically contribute to motility, invasion and egress from infected cells. The MyoA-glideosome is anchored to the inner membrane complex (IMC and is assumed to translocate the components of the circular junction secreted by the micronemes and rhoptries, to the rear of the parasite. Here we comprehensively characterise the class XIV myosin H (MyoH and its associated light chains. We show that the 3 alpha-tubulin suppressor domains, located in MyoH tail, are necessary to anchor this motor to the conoid. Despite the presence of an intact MyoA-glideosome, conditional disruption of TgMyoH severely compromises parasite motility, invasion and egress from infected cells. We demonstrate that MyoH is necessary for the translocation of the circular junction from the tip of the parasite, where secretory organelles exocytosis occurs, to the apical position where the IMC starts. This study attributes for the first time a direct function of the conoid in motility and invasion, and establishes the indispensable role of MyoH in initiating the first step of motility along this unique organelle, which is subsequently relayed by MyoA to enact effective gliding and invasion.

  19. Cell division in Apicomplexan parasites is organized by a homolog of the striated rootlet fiber of algal flagella.

    Science.gov (United States)

    Francia, Maria E; Jordan, Carly N; Patel, Jay D; Sheiner, Lilach; Demerly, Jessica L; Fellows, Justin D; de Leon, Jessica Cruz; Morrissette, Naomi S; Dubremetz, Jean-François; Striepen, Boris

    2012-01-01

    Apicomplexa are intracellular parasites that cause important human diseases including malaria and toxoplasmosis. During host cell infection new parasites are formed through a budding process that parcels out nuclei and organelles into multiple daughters. Budding is remarkably flexible in output and can produce two to thousands of progeny cells. How genomes and daughters are counted and coordinated is unknown. Apicomplexa evolved from single celled flagellated algae, but with the exception of the gametes, lack flagella. Here we demonstrate that a structure that in the algal ancestor served as the rootlet of the flagellar basal bodies is required for parasite cell division. Parasite striated fiber assemblins (SFA) polymerize into a dynamic fiber that emerges from the centrosomes immediately after their duplication. The fiber grows in a polarized fashion and daughter cells form at its distal tip. As the daughter cell is further elaborated it remains physically tethered at its apical end, the conoid and polar ring. Genetic experiments in Toxoplasma gondii demonstrate two essential components of the fiber, TgSFA2 and 3. In the absence of either of these proteins cytokinesis is blocked at its earliest point, the initiation of the daughter microtubule organizing center (MTOC). Mitosis remains unimpeded and mutant cells accumulate numerous nuclei but fail to form daughter cells. The SFA fiber provides a robust spatial and temporal organizer of parasite cell division, a process that appears hard-wired to the centrosome by multiple tethers. Our findings have broader evolutionary implications. We propose that Apicomplexa abandoned flagella for most stages yet retained the organizing principle of the flagellar MTOC. Instead of ensuring appropriate numbers of flagella, the system now positions the apical invasion complexes. This suggests that elements of the invasion apparatus may be derived from flagella or flagellum associated structures.

  20. Estudo da ocorrência da infecção por Hepatozoon sp. em gatos domésticos de Brasília e regiões periurbanas

    OpenAIRE

    2015-01-01

    O Hepatozoon sp., pertencente ao filo Apicomplexa, afeta tanto vertebrados quanto invertebrados hematófagos. Nos felinos domésticos, as formas de transmissão, assim como os vetores envolvidos ainda não foram esclarecidos. No primeiro capítulo determinou-se ocorrência da infecção da Hepatozoonose em felinos de diversas localidades do Distrito Federal, utilizando técnicas moleculares para diagnóstico da doença e caracterização da espécie do parasita. No segundo capítulo relatou-se um caso clí...

  1. INFECCIÓN POR PROTOZOARIOS EN INDIVIDUOS DE TITÍ BEBE LECHE -S. fuscicollis-, TITÍ CABEZA BLANCA -S. oedipus-, TITÍ ARDILLA -S. sciureus-, SURICATO -S. suricatta- Y WALLABIE DE BENNETT -M. rufogriseus-: DESCRIPCIÓN DE CASOS

    OpenAIRE

    G. L. K. López; Peña, J.; C. I. Brieva

    2014-01-01

    La toxoplasmosis es una de las zoonosis parasitarias más comunes y de especial atención en medicina humana y veterinaria en todo el mundo. Toxoplasma gondii comparte mu - chos de sus parámetros biológicos con otros parásitos apicomplexa, pero es único por su extremadamente amplio rango de huéspedes y su especificidad tisular. La susceptibilidad en especies de primates del Nuevo Mundo y diprotodontos a la infección por protozoarios es alta. Bajo condiciones de cautiverio la toxoplasmosis...

  2. 畜禽隐孢子虫病

    Institute of Scientific and Technical Information of China (English)

    彭德旺; 黄秀萍

    1993-01-01

    隐孢子虫隶属于原生动物界(Protozoa),顶器门(Apicomplexa)、孢子虫纲(Sporozoea)、球虫亚纲(Coccidia)、真球虫目(Eucoccidida)、艾美球虫亚目(Eimeriorina)、隐孢子虫科(Cryptosporidiidae)、隐孢子虫属(Cryptosporidium)(Levine等,1980)。迄今已发现可寄生在哺乳类、鸟类、爬行类及鱼类等44种动和人。

  3. Structures of parasitic CDPK domains point to a common mechanism of activation

    Energy Technology Data Exchange (ETDEWEB)

    Wernimont, Amy K.; Amani, Merhnaz; Qiu, Wei; Pizarro, Juan C.; Artz, Jennifer D.; Lin, Yu-Hui; Lew, Jocelyn; Hutchinson, Ashley; Hui, Raymond (Toronto)

    2011-11-23

    We recently determined the first structures of inactivated and calcium-activated calcium-dependent protein kinases (CDPKs) from Apicomplexa. Calcium binding triggered a large conformational change that constituted a new mechanism in calcium signaling and a novel EF-hand fold (CAD, for CDPK activation domain). Thus we set out to determine if this mechanism was universal to all CDPKs. We solved additional CDPK structures, including one from the species Plasmodium. We highlight the similarities in sequence and structure across apicomplexan and plant CDPKs, and strengthen our observations that this novel mechanism could be universal to canonical CDPKs. Our new structures demonstrate more detailed steps in the mechanism of calcium activation and possible key players in regulation. Residues involved in making the largest conformational change are the most conserved across Apicomplexa, leading us to propose that the mechanism is indeed conserved. CpCDPK3{_}CAD and PfCDPK{_}CAD were captured at a possible intermediate conformation, lending insight into the order of activation steps. PfCDPK3{_}CAD adopts an activated fold, despite having an inactive EF-hand sequence in the N-terminal lobe. We propose that for most apicomplexan CDPKs, the mode of activation will be similar to that seen in our structures, while specific regulation of the inactive and active forms will require further investigation.

  4. Identification and characterization of a microneme protein (NcMIC6) in Neospora caninum.

    Science.gov (United States)

    Li, Wensheng; Liu, Jing; Wang, Jing; Fu, Yong; Nan, Huizhu; Liu, Qun

    2015-08-01

    Neospora caninum, an Apicomplexa parasite, is the causative agent of neosporosis. As described for other members of Apicomplexa, microneme proteins (MICs) play a key role in attachment and invasion of host cells by N. caninum. Herein we identified N. caninum microneme protein 6 (NcMIC6) that is orthologous to Toxoplasma gondii microneme protein 6 (TgMIC6). The open reading frame of the NcMIC6 gene is 984 bp and encodes a 327 amino acid peptide. Sequence analysis showed that NcMIC6 included a signal peptide, a transmembrane region, three epidermal growth factor-like (EGF) domains, and two low complexity regions. Antibodies raised against recombinant NcMIC6 recognized an approximately 35-kDa native MIC6 protein in Western blots of N. caninum tachyzoites. Immunofluorescence analysis showed that NcMIC6 had a polar labeling pattern, which was consistent with localization of micronemes in the apical region. Pulse invasion assays showed that NcMIC6 translocated from the apical tip to the posterior end of the parasites. Secretion assays demonstrated that NcMIC6 was released into the supernatants. Importantly, it was clearly revealed by co-immunoprecipitation that NcMIC6 formed a complex with other two soluble microneme proteins (NcMIC1 and NcMIC4). In conclusion, identification and characterization of the novel microneme protein NcMIC6 may contribute to understanding how this protein functions during the parasite motility and host cell invasion.

  5. The apicomplexan inner membrane complex.

    Science.gov (United States)

    Kono, Maya; Prusty, Dhaneswar; Parkinson, John; Gilberger, Tim W

    2013-06-01

    Dinoflagellates, apicomplexans and ciliates are members of the monophyletic supergroup of Alveolata. The protists of this phylogenetic cluster have adapted to various ecological niches and lifestyles. Dinoflagellates and cilates can be found in any aquatic environment, whereas the phylum Apicomplexa solely comprises intracellular parasites. Despite their diversity all alveolates are united by the presence of membranous vesicles, so called alveoli, located beneath the plasma membrane. In addition to strengthening the cytoskeleton, these vesicles appear to possess taxon-specific functionality. In dinoflagellates and ciliates the alveoli predominantly play a structural role and can function as calcium stores. However, for the Apicomplexa, the alveolar vesicles -here jointly called the inner membrane complex (IMC)- are additionally involved in invasion of the host cell and are important scaffold elements during cytokinesis. Recent studies shed light on the architecture of the apicomplexan IMC and the number and diversity of its constituent proteins. This plethora of proteins and their varying evolutionary origin underlines the versatility of the IMC as a result of the adaption to a parasitic lifestyle.

  6. A novel family of Apicomplexan glideosome-associated proteins with an inner membrane-anchoring role.

    Science.gov (United States)

    Bullen, Hayley E; Tonkin, Christopher J; O'Donnell, Rebecca A; Tham, Wai-Hong; Papenfuss, Anthony T; Gould, Sven; Cowman, Alan F; Crabb, Brendan S; Gilson, Paul R

    2009-09-11

    The phylum Apicomplexa are a group of obligate intracellular parasites responsible for a wide range of important diseases. Central to the lifecycle of these unicellular parasites is their ability to migrate through animal tissue and invade target host cells. Apicomplexan movement is generated by a unique system of gliding motility in which substrate adhesins and invasion-related proteins are pulled across the plasma membrane by an underlying actin-myosin motor. The myosins of this motor are inserted into a dual membrane layer called the inner membrane complex (IMC) that is sandwiched between the plasma membrane and an underlying cytoskeletal basket. Central to our understanding of gliding motility is the characterization of proteins residing within the IMC, but to date only a few proteins are known. We report here a novel family of six-pass transmembrane proteins, termed the GAPM family, which are highly conserved and specific to Apicomplexa. In Plasmodium falciparum and Toxoplasma gondii the GAPMs localize to the IMC where they form highly SDS-resistant oligomeric complexes. The GAPMs co-purify with the cytoskeletal alveolin proteins and also to some degree with the actin-myosin motor itself. Hence, these proteins are strong candidates for an IMC-anchoring role, either directly or indirectly tethering the motor to the cytoskeleton.

  7. Inconsistencies of genome annotations in apicomplexan parasites revealed by 5'-end-one-pass and full-length sequences of oligo-capped cDNAs

    Directory of Open Access Journals (Sweden)

    Sugano Sumio

    2009-07-01

    Full Text Available Abstract Background Apicomplexan parasites are causative agents of various diseases including malaria and have been targets of extensive genomic sequencing. We generated 5'-EST collections for six apicomplexa parasites using our full-length oligo-capping cDNA library method. To improve upon the current genome annotations, as well as to validate the importance for physical cDNA clone resources, we generated a large-scale collection of full-length cDNAs for several apicomplexa parasites. Results In this study, we used a total of 61,056 5'-end-single-pass cDNA sequences from Plasmodium falciparum, P. vivax, P. yoelii, P. berghei, Cryptosporidium parvum, and Toxoplasma gondii. We compared these partially sequenced cDNA sequences with the currently annotated gene models and observed significant inconsistencies between the two datasets. In particular, we found that on average 14% of the exons in the current gene models were not supported by any cDNA evidence, and that 16% of the current gene models may contain at least one mis-annotation and should be re-evaluated. We also identified a large number of transcripts that had been previously unidentified. For 732 cDNAs in T. gondii, the entire sequences were determined in order to evaluate the annotated gene models at the complete full-length transcript level. We found that 41% of the T. gondii gene models contained at least one inconsistency. We also identified and confirmed by RT-PCR 140 previously unidentified transcripts found in the intergenic regions of the current gene annotations. We show that the majority of these discrepancies are due to questionable predictions of one or two extra exons in the upstream or downstream regions of the genes. Conclusion Our data indicates that the current gene models are likely to still be incomplete and have much room for improvement. Our unique full-length cDNA information is especially useful for further refinement of the annotations for the genomes of

  8. Padronização de método colorimétrico para avaliação de atividade biológica de substâncias sobre formas taquizoítas de Toxoplasma gondii, com a avaliação de triterpenos ácidos sobre o parasito

    OpenAIRE

    Mariana Rosa da Silva

    2009-01-01

    Toxoplasma gondii é um protozoário pertencente ao filo Apicomplexa, de distribuição mundial, e que infecta diversas espécies hospedeiros, como mamíferos e aves, possuindo como hospedeiros definitivos o gato e outros felídeos, enquanto o homem e outros animais são os seus hospedeiros intermediários. O tratamento é feito, na maioria das vezes, com uma combinação de sulfadiazina e pirimetamina, agindo na via metabólica do ácido fólico, o qual é necessário para a biossíntese de purinas, pirimidin...

  9. Ocurrence of Cryptosporidium spp. in Amazonian manatees (Trichechus inunguis, Natterer, 1883

    Directory of Open Access Journals (Sweden)

    Maria Aparecida da Glória Faustino

    2007-09-01

    Full Text Available The apicomplexa protozoa Cryptosporidium infects several mammals, including terrestrial and aquatic species. In the epidemiology of this infection, the ingestion of water and/or food contamined with oocysts comprises the main mechanism of transmission to susceptible animals. Among the Sirenians, the occurrence of this coccidium has been reported in dugongs (Dugong dugon and Antillean manatee (Trichechus manatus manatus. The present study was conducted with the aim of verifying the occurrence of Cryptosporidium spp. in Amazonian manatee. For this purpose, fecal samples were collected from ten free-ranging Amazonian manatees, two specimens in captivity, and 103 supernatants fecal samples. The samples were processed by the sedimentation method in formol-ether and Kinyoun stain technique for the presence of Cryptosporidium spp.. The positive samples were then submitted to Direct Immunoflorescence Test. The results showed 4.34% (05/115 of positive samples. This is the first report of Cryptosporidium spp. in the Amazonian manatee.

  10. Microparasites of worldwide mullets.

    Science.gov (United States)

    Ovcharenko, Mykola

    2015-01-01

    The present review is focus on parasitic organisms, previously considered as protozoans. Viral, prokaryotic and fungal parasites caused diseases and disorders of worldwide mullets were also observed. Most of the known viruses associated with a high mortality of mullets were detected in Mugil cephalus. Prokaryotic microparasites were registered in M. cephalus, Moolgarda cunnesiu, Liza ramada and Mugil liza. Fungal pathogens were associated with representatives of the genera Aphanomyces, Achlya, Phialemonium, Ichthyophonus. Ichthyophonus sp. can be considered as a potential threat for marine fish aquaculture, especially in culture conditions. A new hyperparasitic microsporidium like organism was recorded in myxozoan Myxobolus parvus infecting grey mullet Liza haematocheilus in the Russian coastal zone of the Sea of Japan. The protozoan representatives of the phyla Dinoflagellata, Euglenozoa, Ciliophora and Apicomplexa were reviewed and analyzed. The review of myxosporean parasites from grey mullets includes 64 species belonging to 13 genera and 9 families infecting 16 fish species

  11. The fine structure of Garnia gonadati and its association with the host cell.

    Science.gov (United States)

    Diniz, J A; Silva, E O; Lainson, R; de Souza, W

    2000-12-01

    Most of the studies on the fine structure of protozoa of the Apicomplexa group have been carried out with members of the ToxoPlasma, Eimeria, and Plasmodium genera. In the present study we analyzed the fine structure of Garnia gonadoti parasitizing the red blood cells of the Amazonian reptile Gonatodes humeralis (Reptilia; Lacertilia). Transmission electron microscopy of thin sections showed that G. gonadoti presented all structures characteristic of the group, including the apicoplast. However, four special features were observed: (1) absence of the hemozoin (malarial) pigment; (2) a group of microtubules associated with the mitochondrion; (3) a vacuole containing electron-dense material, which resembled the acidocalcisome described in trypanosomatids; and (4) a special array of the host-cell endoplasmic reticulum around the parasitophorous vacuole.

  12. Parasites of the hard clam Meretrix meretrix Linnaeus from Western Johor Straits, Malaysian

    Science.gov (United States)

    Azmi, Nur Fauzana; Ghaffar, Mazlan Abd.; Cob, Zaidi Che

    2014-09-01

    This study describes the apicomplexa as well as other parasites infecting organs/tissues of the hard clam Meretrix meretrix Linnaeus, from Merambong Shoal, Western Johor Straits, Malaysia. Samples were collected randomly by hand picking, in November and December 2013. Histological techniques were performed, stained using Masson's Trichrome protocol and observed under light microscope. The results showed that gonad and gill were the most infected organs followed by digestive gland, intestine and adductor muscle. No pathology condition was observed in the mantle. Histophatological examination showed that the gregarine, Nematopsis, unidentified coccidian and Perkinsus were found in the gill and gonad, and also in the numerous hemocytes. Other pathological conditions such as bacteria-like inclusion and intracellular bacteria were also observed in the same organs. Further investigations are needed particularly on other molluscs present at the study area. Understanding the morphology and pathology of parasites infecting mollusks are very important for management of the resources.

  13. Toxoplasma gondii infection in humans in China

    Directory of Open Access Journals (Sweden)

    He Shenyi

    2011-08-01

    Full Text Available Abstract Toxoplasmosis is a zoonotic infection of humans and animals, caused by the opportunistic protozoan Toxoplasma gondii, a parasite belonging to the phylum Apicomplexa. Infection in pregnant women may lead to abortion, stillbirth or other serious consequences in newborns. Infection in immunocompromised patients can be fatal if not treated. On average, one third of people are chronically infected worldwide. Although very limited information from China has been published in the English journals, T. gondii infection is actually a significant human health problem in China. In the present article, we reviewed the clinical features, transmission, prevalence of T. gondii infection in humans in China, and summarized genetic characterizations of reported T. gondii isolates. Educating the public about the risks associated with unhealthy food and life style habits, tracking serological examinations to special populations, and measures to strengthen food and occupational safety are discussed.

  14. Morphology, Ultrastructure and Life Cycle of Vitrella brassicaformis n. sp., n. gen., a Novel Chromerid from the Great Barrier Reef

    KAUST Repository

    Oborník, Miroslav

    2012-03-01

    Chromerida are photoautotrophic alveolates so far only isolated from corals in Australia. It has been shown that these secondary plastid-containing algae are closely related to apicomplexan parasites and share various morphological and molecular characters with both Apicomplexa and Dinophyta. So far, the only known representative of the phylum was Chromera velia. Here we provide a formal description of another chromerid, Vitrella brassicaformis gen. et sp. nov., complemented with a detailed study on its ultrastructure, allowing insight into its life cycle. The novel alga differs significantly from the related chromerid C. velia in life cycle, morphology as well as the plastid genome. Analysis of photosynthetic pigments on the other hand demonstrate that both chromerids lack chlorophyll c, the hallmark of phototrophic chromalveolates. Based on the relatively high divergence between C. velia and V. brassicaformis, we propose their classification into distinct families Chromeraceae and Vitrellaceae. Moreover, we predict a hidden and unexplored diversity of the chromerid algae. © 2011 Elsevier GmbH.

  15. Molecular survey of parasites in introduced Pelophylax perezi (Ranidae) water frogs in the Azores.

    Science.gov (United States)

    James Harris, D; Spigonardi, Maria Pia; Maia, João P M C; Cunha, Regina T

    2013-12-01

    Water frogs, Pelophylax perezi, that are introduced in the Azores, were screened for parasites using PCR primers known to amplify Apicomplexa parasites, and using nematode-specific primers. With the former, three different organisms were detected: Hepatozoon, a trichodinid protozoan ciliate and a possible Stramenopile. Using the latter set of primers, a single unknown spirurid nematode was also detected. Phylogenetic analyses indicate that Hepatozoon detected within amphibian hosts appear to form a clade, although relationships of these parasites do not match the vertebrate intermediate host phylogeny. Regarding the possible Stramenopile, it is unclear whether this organism was actually present on the amphibian or in the water on the surface of the tissue sample. Our findings highlight that many different organisms can be detected with these primers and that they can be used to screen introduced host populations to detect parasites that have been brought with them.

  16. Gibberellin biosynthetic inhibitors make human malaria parasite Plasmodium falciparum cells swell and rupture to death.

    Directory of Open Access Journals (Sweden)

    Tomoko Toyama

    Full Text Available Malaria remains as one of the most devastating infectious disease, and continues to exact an enormous toll in medical cost and days of labor lost especially in the tropics. Effective malaria control and eventual eradication remain a huge challenge, with efficacious antimalarials as important intervention/management tool. Clearly new alternative drugs that are more affordable and with fewer side effects are desirable. After preliminary in vitro assays with plant growth regulators and inhibitors, here, we focus on biosynthetic inhibitors of gibberellin, a plant hormone with many important roles in plant growth, and show their inhibitory effect on the growth of both apicomplexa, Plasmodium falciparum and Toxoplasma gondii. Treatment of P. falciparum cultures with the gibberellin biosynthetic inhibitors resulted in marked morphological changes that can be reversed to a certain degree under hyperosmotic environment. These unique observations suggest that changes in the parasite membrane permeability may explain the pleiotropic effects observed within the intracellular parasites.

  17. Rhoptry protein 5 (ROP5) Is a Key Virulence Factor in Neospora caninum

    Science.gov (United States)

    Ma, Lei; Liu, Jing; Li, Muzi; Fu, Yong; Zhang, Xiao; Liu, Qun

    2017-01-01

    Neospora caninum, of the Apicomplexa phylum, is a common cause of abortions in cattle and nervous system dysfunction in dogs. Rhoptry proteins of Apicomplexa play an important role in virulence. The objectives of this study were to study functions of NcROP5 in N. caninum by deleting the NcROP5 gene from the wild Nc-1 strain. We selected NcROP5 in ToxoDB and successfully constructed an NcROP5 gene-deleted vector, pTCR-NcROP5-CD KO. Then we screened the NcROP5 knockout strains (ΔNcROP5) at the gene, protein and transcription levels. Plaque assay, host cell invasion assay and intracellular proliferation test showed that the ΔNcROP5 strain had less plaque space, weakened invasion capacity and slower intracellular growth. Animal testing showed significantly lower cerebral load of ΔNcROP5 than the load of the Nc-1 strain, as well as a loss of virulence for the ΔNcROP5 strains. Phenotypic analyses using the label-free LC-MS/MS assay-based proteomic method and KEGG pathway enrichment analysis showed a reduction of NcGRA7 transcription and altered expression of multiple proteins including the apicomplexan family of binding proteins. The present study indicated that ROP5 is a key virulence factor in N. caninum in mice. The proteomic profiling of Nc-1 and ΔNcROP5 provided some data on differential proteins. These data provide a foundation for future research of protein functions in N. caninum. PMID:28326073

  18. Novel type of linear mitochondrial genomes with dual flip-flop inversion system in apicomplexan parasites, Babesia microti and Babesia rodhaini

    Directory of Open Access Journals (Sweden)

    Hikosaka Kenji

    2012-11-01

    Full Text Available Abstract Background Mitochondrial (mt genomes vary considerably in size, structure and gene content. The mt genomes of the phylum Apicomplexa, which includes important human pathogens such as the malaria parasite Plasmodium, also show marked diversity of structure. Plasmodium has a concatenated linear mt genome of the smallest size (6-kb; Babesia and Theileria have a linear monomeric mt genome (6.5-kb to 8.2-kb with terminal inverted repeats; Eimeria, which is distantly related to Plasmodium and Babesia/Theileria, possesses a mt genome (6.2-kb with a concatemeric form similar to that of Plasmodium; Cryptosporidium, the earliest branching lineage within the phylum Apicomplexa, has no mt genome. We are interested in the evolutionary origin of linear mt genomes of Babesia/Theileria, and have investigated mt genome structures in members of archaeopiroplasmid, a lineage branched off earlier from Babesia/Theileria. Results The complete mt genomes of archaeopiroplasmid parasites, Babesia microti and Babesia rodhaini, were sequenced. The mt genomes of B. microti (11.1-kb and B. rodhaini (6.9-kb possess two pairs of unique inverted repeats, IR-A and IR-B. Flip-flop inversions between two IR-As and between two IR-Bs appear to generate four distinct genome structures that are present at an equi-molar ratio. An individual parasite contained multiple mt genome structures, with 20 copies and 2 – 3 copies per haploid nuclear genome in B. microti and B. rodhaini, respectively. Conclusion We found a novel linear monomeric mt genome structure of B. microti and B. rhodhaini equipped with dual flip-flop inversion system, by which four distinct genome structures are readily generated. To our knowledge, this study is the first to report the presence of two pairs of distinct IR sequences within a monomeric linear mt genome. The present finding provides insight into further understanding of evolution of mt genome structure.

  19. Novel type of linear mitochondrial genomes with dual flip-flop inversion system in apicomplexan parasites, Babesia microti and Babesia rodhaini

    Science.gov (United States)

    2012-01-01

    Background Mitochondrial (mt) genomes vary considerably in size, structure and gene content. The mt genomes of the phylum Apicomplexa, which includes important human pathogens such as the malaria parasite Plasmodium, also show marked diversity of structure. Plasmodium has a concatenated linear mt genome of the smallest size (6-kb); Babesia and Theileria have a linear monomeric mt genome (6.5-kb to 8.2-kb) with terminal inverted repeats; Eimeria, which is distantly related to Plasmodium and Babesia/Theileria, possesses a mt genome (6.2-kb) with a concatemeric form similar to that of Plasmodium; Cryptosporidium, the earliest branching lineage within the phylum Apicomplexa, has no mt genome. We are interested in the evolutionary origin of linear mt genomes of Babesia/Theileria, and have investigated mt genome structures in members of archaeopiroplasmid, a lineage branched off earlier from Babesia/Theileria. Results The complete mt genomes of archaeopiroplasmid parasites, Babesia microti and Babesia rodhaini, were sequenced. The mt genomes of B. microti (11.1-kb) and B. rodhaini (6.9-kb) possess two pairs of unique inverted repeats, IR-A and IR-B. Flip-flop inversions between two IR-As and between two IR-Bs appear to generate four distinct genome structures that are present at an equi-molar ratio. An individual parasite contained multiple mt genome structures, with 20 copies and 2 – 3 copies per haploid nuclear genome in B. microti and B. rodhaini, respectively. Conclusion We found a novel linear monomeric mt genome structure of B. microti and B. rhodhaini equipped with dual flip-flop inversion system, by which four distinct genome structures are readily generated. To our knowledge, this study is the first to report the presence of two pairs of distinct IR sequences within a monomeric linear mt genome. The present finding provides insight into further understanding of evolution of mt genome structure. PMID:23151128

  20. A transgenic Neospora caninum strain based on mutations of the dihydrofolate reductase-thymidylate synthase gene.

    Science.gov (United States)

    Pereira, Luiz Miguel; Baroni, Luciana; Yatsuda, Ana Patrícia

    2014-03-01

    Neospora caninum is an Apicomplexa parasite related to abortion and losses of fertility in cattle. The amenability of Toxoplasma gondii and Plasmodium to genetic manipulation offers several tools to determine the invasion and replication processes, which support posterior strategies related to the combat of these diseases. For Plasmodium the use of pyrimethamine as an auxiliary drug on malaria treatment has been affected by the rise of resistant strains and the analyses on Dihydrofolate reductase-thymidylate synthase (DHFR-TS) gene indicated several point mutations. In this work we developed a method for stable insertion of genes based on resistance to pyrimethamine. For that, the coding sequence of NcDHFR-TS (Dihydrofolate reductase-thymidylate synthase) was point mutated in two amino acids, generating DHFRM2M3. The DHFRM2M3 flanked by the promoter and 3'UTR of Ncdhfr-ts (Ncdhfr-DHFRM2M3) conferred resistance to pyrimethamine after transfection. For illustration of stability and expression, the cassette Ncdhfr-DHFRM2M3 was ligated to the reporter gene Lac-Z (β-galactosidase enzyme) controlled by the N. caninum tubulin promoter and was transfected and selected in N. caninum. The cassette was integrated into the genome and the selected tachyzoites expressed Lac-Z, allowing the detection of tachyzoites by the CPRG reaction and X-gal precipitation. The obtainment of transgenic N. caninum resistant to pyrimethamine confirms the effects on DHFR-TS among the Apicomplexa members and will support future approaches on pholate inhibitors for N. caninum prophylaxis. The construction of stable tachyzoites based on vectors with N. caninum promoters initiates the molecular manipulation of this parasite independently of T. gondii.

  1. Solar radiation induces non-nuclear perturbations and a false start to regulated exocytosis in Cryptosporidium parvum.

    Science.gov (United States)

    King, Brendon J; Hoefel, Daniel; Wong, Pao Ee; Monis, Paul T

    2010-07-23

    Stratospheric ozone depletion, climate warming and acidification of aquatic ecosystems have resulted in elevated levels of solar radiation reaching many aquatic environments with an increased deleterious impact on a wide range of living organisms. While detrimental effects on living organisms are thought to occur primarily through DNA damage, solar UV can also damage cellular proteins, lipids and signalling pathways. Cryptosporidium, a member of the eukaryotic phylum Apicomplexa, contain numerous vesicular secretory organelles and their discharge via regulated exocytosis is essential for the successful establishment of infection. Using flow cytometric techniques we demonstrate that solar UV rapidly induces sporozoite exocytosis resulting in a significant reduction in the ability of sporozoites to attach and invade host cells. We found that solar UV induced sporozoite membrane depolarization, resulting in reduced cellular ATP and increased cytosolic calcium. These changes were accompanied by a reduction in the internal granularity of sporozoites, indicative of apical organelle discharge, which was confirmed by analysis of sporozoites with an exocytosis-sensitive dye. The precise timing of apical organelle discharge in the presence of a compatible host cell is critical for sporozoite attachment and invasion. Our results demonstrate for the first time how solar UV radiation can interfere with exocytosis, a fundamental cellular process in all eukaryotic cells. We contend that not only may the forecast increases in solar radiation in both aquatic and terrestrial environments significantly affect members of the Apicomplexa, solar UV-induced membrane depolarizations resulting in cytosolic calcium perturbation may affect a wider range of eukaryotic organisms through antagonistic effects on a myriad of calcium dependant cellular functions.

  2. Ocorrência de anticorpos anti-Neospora caninum em pequenas propriedades leiteiras do Uruguai Occurrence of anti-Neospora caninum antibodies in small dairy farms in Uruguay

    Directory of Open Access Journals (Sweden)

    Agustín Furtado

    2011-04-01

    Full Text Available Neosporose é uma doença de distribuição mundial causada por um protozoário (Apicomplexa, Sarcocystidae, denominado Neospora caninum (N. caninum. Na América Latina, o protozoário foi diagnosticado no Uruguai, Brasil, Argentina, Chile, Paraguai e Peru. No Uruguai a prevalência em rebanhos leiteiros não foi determinada, havendo somente levantamentos sorológicos de algumas regiões do país em propriedades rurais de médio e grande porte. O objetivo deste trabalho foi determinar a presença de animais sorologicamente positivos contra N. caninum em bacias leiteiras de pequenas propriedades com baixos recursos socioeconômicos da zona central do Uruguai (Estados de Durazno e Tacuarembó. Utilizando um Kit de ELISA comercial, foram analisados 734 soros provenientes de vacas leiteiras adultas, obtendo-se 211 positivos (28,8%, 517 negativos (70,5% e seis animais com resultado não determinado (0,7%. Nossos resultados demonstram a exposição destes rebanhos ao parasito, sendo este o primeiro inquérito sorológico de N. caninum em bacias leiteiras de pequenas propriedades no Uruguai.Neosporosis is a worldwide disease caused by a protozoan (Apicomplexa, Sarcocystidae, called Neospora caninum (N. caninum. In Latin America was diagnosed in Uruguay, Brazil, Argentina, Chile, Paraguay and Peru. In Uruguay, the prevalence in dairy cattle is undetermined, with only a few reports in some areas from medium and large farmers. The main of this study was to determine the presence of serologically positive animals against N. caninum in small dairy farmers in critical context from central region of Uruguay (Departments of Durazno and Tacuarembó. Using a commercial ELISA kit, 734 sera of adult dairy cows were analyzed, resulting in 211 positive (28.8%, 517 negative (70.5% and six animals with uncertain outcome (0.7%. The results demonstrated the exposure of cattle to the parasite, which is the first serological survey of N. caninum in basins of small dairy

  3. Parasites of economically important bivalves from the southern coast of Bahia State, Brazil Parasitos de bivalves de interesse econômico no Litoral Sul do Estado da Bahia, Brasil

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    Gabriela Calvi Zeidan

    2012-12-01

    Full Text Available This study investigated the parasites of three commercially important bivalve species (Crassostrea rhizophorae, Mytella guyanensis and Lucina pectinata from the southern coast of Bahia, Brazil. A total of 540 specimens were collected in August 2009 and February 2010, at three localities. The bivalve specimens were measured on their longest axis, opened, and macroscopically examined for the presence of parasites or signs of disease. They were then fixed in Davidson' solution and subjected to routine histological processing, with paraffin embedding and H&E staining; next, the specimens were examined under a light microscope. No parasites were observed associated with L. pectinata. Rickettsia-like organisms (RLOs, Sphenophrya sp. (Ciliophora, Nematopsis sp. (Apicomplexa, Urastoma sp. (Turbellaria and Bucephalus sp. (Digenea were observed in both C. rhizophorae and M. guyanensis, as well as Ancistrocoma sp. (Ciliophora and Tylocephalum sp. (Cestoda in the former. A high prevalence of Nematopsis sp. was seen, but caused no apparent damage to the host. Bucephalus sp. caused the destruction of tissues, with castration, but showed low prevalence. The other parasites occurred in low prevalence and intensity, without causing significant damage.Neste estudo foram investigados os parasitos de três espécies de bivalves de interesse econômico (Crassostrea rhizophorae, Mytella guyanensis e Lucina pectinata da Bahia. Foram analisados 540 exemplares, obtidos em duas coletas (agosto-2009 e fevereiro-2010, em três localidades. Os bivalves foram medidos quanto ao seu maior eixo, abertos e examinados macroscopicamente quanto à presença de parasitos ou sinais de enfermidades. Depois disso, foram fixados em solução de Davidson e processados por rotina de histologia, com inclusão em parafina e coloração com H&E. O material foi examinado ao microscópio de luz. Nenhum parasito esteve associado a L. pectinata. Bactérias do tipo RLOs (organismos assemelhados a

  4. 弓形虫与疟原虫入侵引起宿主细胞骨架重组相关GTP酶不同定位的观察%Observation on different localization of GTPases related to host cytoskeleton reorganization triggered by Toxoplasma gondii and Plasmodium falciparum infection

    Institute of Scientific and Technical Information of China (English)

    陈艾媛; 娜仁花; 彭鸿娟; 赵亚

    2012-01-01

    Both Toxoplasmagondii and Plasmodium spp. belong to the intracellular protozoa in Order Eucoccidiida, Class Sporozoea, and Phylum Apicomplexa. They dwell in the parasitophorons vaenole lor parasitism , development and multiplication alter recruitment . The invasion of these intracellular protozoans into host cells requires the cytoskeleton reorganization of the host cell . Rho GTPases are the important enzymes in regulation of cytoskeleton reorganization in mammalian cells inclu -ding nucleated cells and erythrocytes . We found in our research that host cell RhoA and Racl GTPase were recruited to the par-asitophorous vacuole membrane (PV M ) of T. gondii and showed a high accumulation on the PV M after T. gondii tachyzoite invading the host cell. On the other hand , this accumulation of the Rho GTPases on the PV M was not observed after Plasmodium falciparum merozoites invading erythrocytes . The different distribution of RhoA and RaclGTPase in the host cell after the invasion of T. gondii tachyzoites and Plasmodium falciparum merozoites indicated the different way for the regulation of cytoskeleton reorganization in host cells upon the parasites invasion .%目的 方法,结果,结论弓形虫与疟原虫均是顶复门(Phylum Apicomplexa),孢子纲(Class Sporozoea), 真球虫目(Order Eucoccidiida)的细胞内寄生原虫,入侵宿主细胞后均寄生于纳虫泡内进行发育增殖.细胞内寄生原虫的入侵均需要宿主细胞的细胞骨架发生重组,RhoGTP酶是哺乳动物细胞(有核细胞及红细胞)调节细胞骨架重组的重要酶类.我们在研究中发现宿主细胞的RhoA及Rac1GTP酶在弓形虫速殖子侵染后被纳入了纳虫泡膜(Parasitophorous Vacuole Membrane,PVM)上并高丰度聚集,然而在疟原虫裂殖子侵染的红细胞内却没有发现这两种GTP酶在纳虫泡膜上聚集的现象.宿主细胞RhoA及Rac1GTP酶在弓形虫及疟原虫感染宿主细胞后的不同分布,显示这两种原虫感染引起宿主细

  5. Translational repression of the cpw-wpc gene family in the malaria parasite Plasmodium

    KAUST Repository

    Rao, Pavitra N.

    2016-06-14

    The technical challenges of working with the sexual stages of the malaria parasite Plasmodium have hindered the characterization of sexual stage antigens in the quest for a successful malaria transmission-blocking vaccine. One such predicted and largely uncharacterized group of sexual stage candidate antigens is the CPW-WPC family of proteins. CPW-WPC proteins are named for a characteristic domain that contains two conserved motifs, CPxxW and WPC. Conserved across Apicomplexa, this family is also present earlier in the Alveolata in the free-living, non-parasitophorous, photosynthetic chromerids, Chromera and Vitrella. In P. falciparum and P. berghei blood stage parasites the transcripts of all nine cpw-wpc genes have been detected in gametocytes. RNA immunoprecipitation followed by reverse transcriptase-PCR reveals all P. berghei cpw-wpc transcripts to be bound by the translational repressors DOZI and CITH, and thus are likely under translational control prior to transmission from the rodent host to the mosquito vector in P. berghei. The GFP tagging of two endogenous P. berghei genes confirmed translational silencing in the gametocyte and translation in ookinetes. Establishing a luciferase transgene assay we show that the 3′ untranslated region of PF3D7_1331400 controls protein expression of this reporter in P. falciparum gametocytes. Our analyses suggest that cpw-wpc genes are translationally silenced in gametocytes across Plasmodium spp. and activated during ookinete formation and thus may have a role in transmission to the mosquito.

  6. The contribution of DNA slippage to eukaryotic nuclear 18S rRNA evolution.

    Science.gov (United States)

    Hancock, J M

    1995-06-01

    Six of 204 eukaryotic nuclear small-subunit ribosomal RNA sequences analyzed show a highly significant degree of clustering of short sequence motifs that indicates the fixation of products of replication slippage within them in their recent evolutionary history. A further 72 sequences show weaker indications of sequence repetition. Repetitive sequences in SSU rRNAs are preferentially located in variable regions and in particular in V4 and V7. The conserved region immediately 5' to V7 (C7) is also consistently repetitive. Whereas variable regions vary in length and appear to have evolved by the fixation of slippage products, C7 shows no indication of length variation. Repetition within C7 is therefore either not a consequence of slippage or reflects very ancient slippage events. The phylogenetic distribution of sequence simplicity in small-subunit rRNAs is patchy, being largely confined to the Mammalia, Apicomplexa, Tetrahymenidae, and Trypanosomatidae. The regions of the molecule associated with sequence simplicity vary with taxonomic grouping as do the sequence motifs undergoing slippage. Comparison of rates of insertion and substitution in a lineage within the genus Plasmodium confirms that both rates are higher in variable regions than in conserved regions. The insertion rate in variable regions is substantially lower than the substitution rate, suggesting that selection acts more strongly on slippage products than on point mutations in these regions. Patterns of coevolution between variable regions may reflect the consequences of selection acting on the incorporation of slippage-derived sequences across the gene.

  7. The apical complex provides a regulated gateway for secretion of invasion factors in Toxoplasma.

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    Nicholas J Katris

    2014-04-01

    Full Text Available The apical complex is the definitive cell structure of phylum Apicomplexa, and is the focus of the events of host cell penetration and the establishment of intracellular parasitism. Despite the importance of this structure, its molecular composition is relatively poorly known and few studies have experimentally tested its functions. We have characterized a novel Toxoplasma gondii protein, RNG2, that is located at the apical polar ring--the common structural element of apical complexes. During cell division, RNG2 is first recruited to centrosomes immediately after their duplication, confirming that assembly of the new apical complex commences as one of the earliest events of cell replication. RNG2 subsequently forms a ring, with the carboxy- and amino-termini anchored to the apical polar ring and mobile conoid, respectively, linking these two structures. Super-resolution microscopy resolves these two termini, and reveals that RNG2 orientation flips during invasion when the conoid is extruded. Inducible knockdown of RNG2 strongly inhibits host cell invasion. Consistent with this, secretion of micronemes is prevented in the absence of RNG2. This block, however, can be fully or partially overcome by exogenous stimulation of calcium or cGMP signaling pathways, respectively, implicating the apical complex directly in these signaling events. RNG2 demonstrates for the first time a role for the apical complex in controlling secretion of invasion factors in this important group of parasites.

  8. Forward genetic analysis of the apicomplexan cell division cycle in Toxoplasma gondii.

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    Marc-Jan Gubbels

    2008-02-01

    Full Text Available Apicomplexa are obligate intracellular pathogens that have fine-tuned their proliferative strategies to match a large variety of host cells. A critical aspect of this adaptation is a flexible cell cycle that remains poorly understood at the mechanistic level. Here we describe a forward genetic dissection of the apicomplexan cell cycle using the Toxoplasma model. By high-throughput screening, we have isolated 165 temperature sensitive parasite growth mutants. Phenotypic analysis of these mutants suggests regulated progression through the parasite cell cycle with defined phases and checkpoints. These analyses also highlight the critical importance of the peculiar intranuclear spindle as the physical hub of cell cycle regulation. To link these phenotypes to parasite genes, we have developed a robust complementation system based on a genomic cosmid library. Using this approach, we have so far complemented 22 temperature sensitive mutants and identified 18 candidate loci, eight of which were independently confirmed using a set of sequenced and arrayed cosmids. For three of these loci we have identified the mutant allele. The genes identified include regulators of spindle formation, nuclear trafficking, and protein degradation. The genetic approach described here should be widely applicable to numerous essential aspects of parasite biology.

  9. Structure and function of a G-actin sequestering protein with a vital role in malaria oocyst development inside the mosquito vector.

    Science.gov (United States)

    Hliscs, Marion; Sattler, Julia M; Tempel, Wolfram; Artz, Jennifer D; Dong, Aiping; Hui, Raymond; Matuschewski, Kai; Schüler, Herwig

    2010-04-09

    Cyclase-associated proteins (CAPs) are evolutionary conserved G-actin-binding proteins that regulate microfilament turnover. CAPs have a modular structure consisting of an N-terminal adenylate cyclase binding domain, a central proline-rich segment, and a C-terminal actin binding domain. Protozoan parasites of the phylum Apicomplexa, such as Cryptosporidium and the malaria parasite Plasmodium, express small CAP orthologs with homology to the C-terminal actin binding domain (C-CAP). Here, we demonstrate by reverse genetics that C-CAP is dispensable for the pathogenic Plasmodium blood stages. However, c-cap(-) parasites display a complete defect in oocyst development in the insect vector. By trans-species complementation we show that the Cryptosporidium parvum ortholog complements the Plasmodium gene functions. Purified recombinant C. parvum C-CAP protein binds actin monomers and prevents actin polymerization. The crystal structure of C. parvum C-CAP shows two monomers with a right-handed beta-helical fold intercalated at their C termini to form the putative physiological dimer. Our results reveal a specific vital role for an apicomplexan G-actin-binding protein during sporogony, the parasite replication phase that precedes formation of malaria transmission stages. This study also exemplifies how Plasmodium reverse genetics combined with biochemical and structural analyses of orthologous proteins can offer a fast track toward systematic gene characterization in apicomplexan parasites.

  10. Holding back the microfilament--structural insights into actin and the actin-monomer-binding proteins of apicomplexan parasites.

    Science.gov (United States)

    Olshina, Maya A; Wong, Wilson; Baum, Jake

    2012-05-01

    Parasites from the phylum Apicomplexa are responsible for several major diseases of man, including malaria and toxoplasmosis. These highly motile protozoa use a conserved actomyosin-based mode of movement to power tissue traversal and host cell invasion. The mode termed as 'gliding motility' relies on the dynamic turnover of actin, whose polymerisation state is controlled by a markedly limited number of identifiable regulators when compared with other eukaryotic cells. Recent studies of apicomplexan actin regulator structure-in particular those of the core triad of monomer-binding proteins, actin-depolymerising factor/cofilin, cyclase-associated protein/Srv2, and profilin-have provided new insights into possible mechanisms of actin regulation in parasite cells, highlighting divergent structural features and functions to regulators from other cellular systems. Furthermore, the unusual nature of apicomplexan actin itself is increasingly coming into the spotlight. Here, we review recent advances in understanding of the structure and function of actin and its regulators in apicomplexan parasites. In particular we explore the paradox between there being an abundance of unpolymerised actin, its having a seemingly increased potential to form filaments relative to vertebrate actin, and the apparent lack of visible, stable filaments in parasite cells.

  11. Molecular characterization of Toxoplasma gondii formin 3, an actin nucleator dispensable for tachyzoite growth and motility.

    Science.gov (United States)

    Daher, Wassim; Klages, Natacha; Carlier, Marie-France; Soldati-Favre, Dominique

    2012-03-01

    Toxoplasma gondii belongs to the phylum Apicomplexa, a group of obligate intracellular parasites that rely on gliding motility to enter host cells. Drugs interfering with the actin cytoskeleton block parasite motility, host cell invasion, and egress from infected cells. Myosin A, profilin, formin 1, formin 2, and actin-depolymerizing factor have all been implicated in parasite motility, yet little is known regarding the importance of actin polymerization and other myosins for the remaining steps of the parasite lytic cycle. Here we establish that T. gondii formin 3 (TgFRM3), a newly described formin homology 2 domain (FH2)-containing protein, binds to Toxoplasma actin and nucleates rabbit actin assembly in vitro. TgFRM3 expressed as a transgene exhibits a patchy localization at several distinct structures within the parasite. Disruption of the TgFRM3 gene by double homologous recombination in a ku80-ko strain reveals no vital function for tachyzoite propagation in vitro, which is consistent with its weak level of expression in this life stage. Conditional stabilization of truncated forms of TgFRM3 suggests that different regions of the molecule contribute to distinct localizations. Moreover, expression of TgFRM3 lacking the C-terminal domain severely affects parasite growth and replication. This work provides a first insight into how this specialized formin, restricted to the group of coccidia, completes its actin-nucleating activity.

  12. Cloning and analysis of a Toxoplasma gondii histone acetyltransferase: a novel chromatin remodelling factor in Apicomplexan parasites.

    Science.gov (United States)

    Hettmann, C; Soldati, D

    1999-11-15

    The yeast transcriptional adaptor GCN5 functions as a histone acetyltransferase, directly linking chromatin modification to transcriptional regulation. Homologues of yeast GCN5 have been found in Tetrahymena, Drosophila, Arabidopsis and human, suggesting that this pathway of chromatin remodelling is evolutionarily conserved. Consistent with this view, we have identified the Toxoplasma gondii homologue, referred to here as TgGCN5. The gene codes for a protein of 474 amino acids with an estimated molecular mass of 53 kDa. The protein reveals two regions of close similarity with the GCN5 family members, the HAT domain and the bromodomain. Tg GCN5 occurs in a single copy in the T.gondii genome. The introduction of a second copy of TgGCN5 in T.gondii tachyzoites is toxic unless the HAT activity is disrupted by a single point mutation. Full TgGCN5 does not complement the growth defect in a yeast gcn5 (-)mutant strain, but a chimera comprising the T.gondii HAT domain fused to the remainder of yGCN5 does. These data show that T.gondii GNC5 is a histone acetyltransferase attesting to the significance of chromatin remodelling in gene regulation of Apicomplexa.

  13. ArtinM, a D-mannose-binding lectin from Artocarpus integrifolia, plays a potent adjuvant and immunostimulatory role in immunization against Neospora caninum.

    Science.gov (United States)

    Cardoso, Mariana R D; Mota, Caroline M; Ribeiro, Dâmaso P; Santiago, Fernanda M; Carvalho, Julianne V; Araujo, Ester C B; Silva, Neide M; Mineo, Tiago W P; Roque-Barreira, Maria C; Mineo, José R; Silva, Deise A O

    2011-11-15

    ArtinM and Jacalin (JAC) are lectins from the jackfruit (Artocarpus integrifolia) that have important role in modulation of immune responses to pathogens. Neospora caninum is an Apicomplexa parasite that causes neuromuscular disease in dogs and reproductive disorders in cattle, with economic impact on the livestock industry. Hence, we evaluated the adjuvant effect of ArtinM and JAC in immunization of mice against neosporosis. Six C57BL/6 mouse groups were subcutaneously immunized three times at 2-week intervals with Neospora lysate antigen (NLA) associated with lectins (NLA+ArtinM and NLA+JAC), NLA, ArtinM and JAC alone, and PBS (infection control). Animals were challenged with lethal dose of Nc-1 isolate and evaluated for morbidity, mortality, specific antibody response, cytokine production by spleen cells, brain parasite burden and inflammation. Our results demonstrated that ArtinM was able to increase NLA immunogenicity, inducing the highest levels of specific total IgG and IgG2a/IgG1 ratio, ex vivo Th1 cytokine production, increased survival, the lowest brain parasite burden, along with the highest inflammation scores. In contrast, NLA+JAC immunized group showed intermediate survival, the highest brain parasite burden and the lowest inflammation scores. In conclusion, ArtinM presents stronger immunostimulatory and adjuvant effect than Jacalin in immunization of mice against neosporosis, by inducing a protective Th1-biased pro-inflammatory immune response and higher protection after parasite challenge.

  14. Eimeria that infect fish are diverse and are related to, but distinct from, those that infect terrestrial vertebrates.

    Science.gov (United States)

    Molnár, Kálmán; Ostoros, Györgyi; Dunams-Morel, Detiger; Rosenthal, Benjamin M

    2012-12-01

    The Eimeria are ubiquitous parasites (Phylum: Apicomplexa; family: Coccidia) of the gut epithelium of vertebrates which complete their development in a single host species and whose sporocysts may be recognized by the presence of a Stieda body through which their sporozoites excyst. Their diversity and relationship to other kinds of coccidia have been successfully explored by molecular systematic studies based on the sequencing the 18S ribosomal DNA. To date, most attention has been paid to the diversity and evolutionary relationships of Eimeria spp. parasitizing terrestrial vertebrates, most especially those species infecting domesticated birds and mammals. Regrettably, no Eimeria have yet been considered from the Earth's first vertebrates: the fish. If Eimeria first evolved in fish, then extant piscine parasites should comprise a deeply branching assemblage at the base of well-constructed phylogenetic trees. Here, we sequenced portions of ribosomal DNA from several such isolates (from Eimeria anguillae, Eimeria daviesae, Eimeria percae, Eimeria variabilis, Eimeria rutili and Eimeria nemethi) and compared them to one another as well as to other available sequences from the parasites of fish and terrestrial vertebrates, in order to better understand their diversity and origins. By establishing that such piscine parasites comprise a deeply branching clade at the base of the Eimeriidae, these data substantiate the hypothesis that Eimeria may have originated in fish. Plainly, a great deal of coccidian diversity awaits future discovery and description.

  15. Two new Eimeria species parasitic in corncrakes (Crex crex) (Gruiformes: Rallidae) in the United Kingdom.

    Science.gov (United States)

    Jeanes, C; Vaughan-Higgins, R; Green, R E; Sainsbury, A W; Marshall, R N; Blake, D P

    2013-08-01

    In this study we describe 2 new species of coccidia (Apicomplexa: Eimeriidae) parasites isolated from the feces of corncrake (Crex crex) (Gruiformes: Rallidae), bred in captivity in the U.K. Oocysts of Eimeria crecis n. sp. were approximately spherical and measured 15.3 μm (13-18) × 14.3 (12-16), providing an oocyst shape index of 1.1. A micropyle and oocyst residuum were absent, but a polar granule was present. Oocysts of Eimeria nenei n. sp. were ellipsoidal and measured 23.6 (21-26) × 18.1 (17-20), providing an oocyst shape index of 1.3. A micropyle and polar granule were present. Surveying free-living, wild adult corncrakes in Scotland (U.K.) demonstrated both parasite species to be widespread. These are the first species described to infect the corncrake, and they are distinct from those previously found to infect members of the closely related crane family (Gruiformes: Gruidae). Partial amplification and sequencing of the 18S rRNA gene and internal transcribed spacer 2 indicated a close relationship between the 2 proposed new species as a group distinct from the Eimeria species known to infect cranes. These newly identified parasite species have been associated with enteric disease in corncrakes being prepared for reproduction in captivity and reintroduction into England (U.K.).

  16. Composite genome map and recombination parameters derived from three archetypal lineages of Toxoplasma gondii.

    Science.gov (United States)

    Khan, Asis; Taylor, Sonya; Su, Chunlei; Mackey, Aaron J; Boyle, Jon; Cole, Robert; Glover, Darius; Tang, Keliang; Paulsen, Ian T; Berriman, Matt; Boothroyd, John C; Pfefferkorn, Elmer R; Dubey, J P; Ajioka, James W; Roos, David S; Wootton, John C; Sibley, L David

    2005-01-01

    Toxoplasma gondii is a highly successful protozoan parasite in the phylum Apicomplexa, which contains numerous animal and human pathogens. T.gondii is amenable to cellular, biochemical, molecular and genetic studies, making it a model for the biology of this important group of parasites. To facilitate forward genetic analysis, we have developed a high-resolution genetic linkage map for T.gondii. The genetic map was used to assemble the scaffolds from a 10X shotgun whole genome sequence, thus defining 14 chromosomes with markers spaced at approximately 300 kb intervals across the genome. Fourteen chromosomes were identified comprising a total genetic size of approximately 592 cM and an average map unit of approximately 104 kb/cM. Analysis of the genetic parameters in T.gondii revealed a high frequency of closely adjacent, apparent double crossover events that may represent gene conversions. In addition, we detected large regions of genetic homogeneity among the archetypal clonal lineages, reflecting the relatively few genetic outbreeding events that have occurred since their recent origin. Despite these unusual features, linkage analysis proved to be effective in mapping the loci determining several drug resistances. The resulting genome map provides a framework for analysis of complex traits such as virulence and transmission, and for comparative population genetic studies.

  17. Secretion of Antonospora (Paranosema) locustae proteins into infected cells suggests an active role of microsporidia in the control of host programs and metabolic processes.

    Science.gov (United States)

    Senderskiy, Igor V; Timofeev, Sergey A; Seliverstova, Elena V; Pavlova, Olga A; Dolgikh, Viacheslav V

    2014-01-01

    Molecular tools of the intracellular protozoan pathogens Apicomplexa and Kinetoplastida for manipulation of host cell machinery have been the focus of investigation for approximately two decades. Microsporidia, fungi-related microorganisms forming another large group of obligate intracellular parasites, are characterized by development in direct contact with host cytoplasm (the majority of species), strong minimization of cell machinery, and acquisition of unique transporters to exploit host metabolic system. All the aforementioned features are suggestive of the ability of microsporidia to modify host metabolic and regulatory pathways. Seven proteins of the microsporidium Antonospora (Paranosema) locustae with predicted signal peptides but without transmembrane domains were overexpressed in Escherichia coli. Western-blot analysis with antibodies against recombinant products showed secretion of parasite proteins from different functional categories into the infected host cell. Secretion of parasite hexokinase and α/β-hydrolase was confirmed by immunofluorescence microscopy. In addition, this method showed specific accumulation of A. locustae hexokinase in host nuclei. Expression of hexokinase, trehalase, and two leucine-rich repeat proteins without any exogenous signal peptide led to their secretion in the yeast Pichia pastoris. In contrast, α/β-hydrolase was not found in the culture medium, though a significant amount of this enzyme accumulated in the yeast membrane fraction. These results suggest that microsporidia possess a broad set of enzymes and regulatory proteins secreted into infected cells to control host metabolic processes and molecular programs.

  18. Secretion of Antonospora (Paranosema locustae proteins into infected cells suggests an active role of microsporidia in the control of host programs and metabolic processes.

    Directory of Open Access Journals (Sweden)

    Igor V Senderskiy

    Full Text Available Molecular tools of the intracellular protozoan pathogens Apicomplexa and Kinetoplastida for manipulation of host cell machinery have been the focus of investigation for approximately two decades. Microsporidia, fungi-related microorganisms forming another large group of obligate intracellular parasites, are characterized by development in direct contact with host cytoplasm (the majority of species, strong minimization of cell machinery, and acquisition of unique transporters to exploit host metabolic system. All the aforementioned features are suggestive of the ability of microsporidia to modify host metabolic and regulatory pathways. Seven proteins of the microsporidium Antonospora (Paranosema locustae with predicted signal peptides but without transmembrane domains were overexpressed in Escherichia coli. Western-blot analysis with antibodies against recombinant products showed secretion of parasite proteins from different functional categories into the infected host cell. Secretion of parasite hexokinase and α/β-hydrolase was confirmed by immunofluorescence microscopy. In addition, this method showed specific accumulation of A. locustae hexokinase in host nuclei. Expression of hexokinase, trehalase, and two leucine-rich repeat proteins without any exogenous signal peptide led to their secretion in the yeast Pichia pastoris. In contrast, α/β-hydrolase was not found in the culture medium, though a significant amount of this enzyme accumulated in the yeast membrane fraction. These results suggest that microsporidia possess a broad set of enzymes and regulatory proteins secreted into infected cells to control host metabolic processes and molecular programs.

  19. Subcompartmentalisation of proteins in the rhoptries correlates with ordered events of erythrocyte invasion by the blood stage malaria parasite.

    Directory of Open Access Journals (Sweden)

    Elizabeth S Zuccala

    Full Text Available Host cell infection by apicomplexan parasites plays an essential role in lifecycle progression for these obligate intracellular pathogens. For most species, including the etiological agents of malaria and toxoplasmosis, infection requires active host-cell invasion dependent on formation of a tight junction - the organising interface between parasite and host cell during entry. Formation of this structure is not, however, shared across all Apicomplexa or indeed all parasite lifecycle stages. Here, using an in silico integrative genomic search and endogenous gene-tagging strategy, we sought to characterise proteins that function specifically during junction-dependent invasion, a class of proteins we term invasins to distinguish them from adhesins that function in species specific host-cell recognition. High-definition imaging of tagged Plasmodium falciparum invasins localised proteins to multiple cellular compartments of the blood stage merozoite. This includes several that localise to distinct subcompartments within the rhoptries. While originating from the same organelle, however, each has very different dynamics during invasion. Apical Sushi Protein and Rhoptry Neck protein 2 release early, following the junction, whilst a novel rhoptry protein PFF0645c releases only after invasion is complete. This supports the idea that organisation of proteins within a secretory organelle determines the order and destination of protein secretion and provides a localisation-based classification strategy for predicting invasin function during apicomplexan parasite invasion.

  20. First Molecular Characterization of Theileria ornithorhynchi Mackerras, 1959: yet Another Challenge to the Systematics of the Piroplasms.

    Science.gov (United States)

    Paparini, Andrea; Macgregor, James; Ryan, Una M; Irwin, Peter J

    2015-12-01

    Piroplasms, tick-transmitted Apicomplexa of the genera Theileria, Babesia and Cytauxzoon, are blood-borne parasites of clinical and veterinary importance. The order Piroplasmida shows a puzzling systematics characterized by multiple clades, soft polytomies and paraphyletic/polyphyletic genera. In the present study, screening of platypuses (Ornithorhynchus anatinus), was performed to infer the parasite molecular phylogeny. DNA was extracted from blood, ectoparasites and tick eggs and the 18S rRNA- hsp70-genes were used for the phylogenetic reconstructions. Microscopic analyses detected pleomorphic intra-erythrocytic organisms and tetrads consistent with previous descriptions of Theileria ornithorhynchi Mackerras, 1959, but observation of possible schizonts could not be confirmed. DNA sequences obtained from blood and ticks allowed resolving the systematics of the first piroplasm infecting a monotreme host. Molecularly, T. ornithorhynchi formed a novel monophyletic group, basal to most known piroplasms' clades. The ancestral position of this clade, isolated from an ancient lineage of mammalian host appears particularly fascinating. The present paper discusses the inadequacies of the current molecular systematics for the Piroplasmida and the consequences of incomplete sampling, morphology-based classification and ambiguous microscopic identifications. Likely when the current sampling bias is rectified and more sequence data is made available, the phylogenetic position of T. ornithorhynchi will be further contextualized without ambiguity.

  1. Phylogenetic relationship of Hepatozoon blood parasites found in snakes from Africa, America and Asia.

    Science.gov (United States)

    Haklová, B; Majláthová, V; Majláth, I; Harris, D J; Petrilla, V; Litschka-Koen, T; Oros, M; Peťko, B

    2014-03-01

    The blood parasites from the genus Hepatozoon Miller, 1908 (Apicomplexa: Adeleida: Hepatozoidae) represent the most common intracellular protozoan parasites found in snakes. In the present study, we examined 209 individuals of snakes, from different zoogeographical regions (Africa, America, Asia and Europe), for the occurrence of blood parasites using both molecular and microscopic examination methods, and assess phylogenetic relationships of all Hepatozoon parasites from snakes for the first time. In total, 178 blood smears obtained from 209 individuals, representing 40 species, were examined, from which Hepatozoon unicellular parasites were found in 26 samples (14·6% prevalence). Out of 180 samples tested by molecular method polymerase chain reaction (PCR), the presence of parasites was observed in 21 individuals (prevalence 11·6%): 14 snakes from Africa belonging to six genera (Dendroaspis, Dispholidus, Mehelya, Naja, Philothamnus and Python), five snakes from Asia from the genus Morelia and two snakes from America, from two genera (Coluber and Corallus). The intensity of infection varied from one to 1433 infected cells per 10 000 erythrocytes. Results of phylogenetic analyses (Bayesian and Maximum Likelihood) revealed the existence of five haplotypes divided into four main lineages. The present data also indicate neither geographical pattern of studied Hepatozoon sp., nor congruency in the host association.

  2. Seroprevalence of Toxoplasma gondii in hunted wild boars (Sus scrofa) from southeastern France.

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    Roqueplo, Cedric; Blaga, Radu; Jean-Lou, Marie; Vallee, Isabelle; Davoust, Bernard

    2017-01-25

    Toxoplasma gondii (Nicolle et Manceaux, 1908) is an obligate intracellular, parasitic protozoan within the phylum Apicomplexa that causes toxoplasmosis in mammalian hosts (including humans) and birds. Since meat of wild boar, Sus scrofa (Linnaeus), has been demonstrated to be a potential source of human infection, a careful evaluation of the prevalence of infection with T. gondii in hunted animals is needed to protect public health. In the Var area in southeastern France, we performed a spatio-temporal survey in order to investigate the prevalence of IgG antibodies in wild boars shot by hunters in the Canjuers military camp during two subsequent hunting seasons. Of 841 wild boars screened, antibodies (IgG) to T. gondii (modified agglutination test, cut-off 1 : 6) were found in 141 (16.8%) muscle extract samples. A significant association (p < 0.001) was found between positivity and age, but not gender, and hunting districts. The results obtained indicate that consumption of raw or undercooked meat from wild boars carries an important risk of infection with T. gondii. Wild boars may be considered as a bioindicator of parasite circulation in this ecosystem.

  3. CenH3 evolution reflects meiotic symmetry as predicted by the centromere drive model.

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    Zedek, František; Bureš, Petr

    2016-09-15

    The centromere drive model explaining rapid evolution of eukaryotic centromeres predicts higher frequency of positive selection acting on centromeric histone H3 (CenH3) in clades with asymmetric meiosis compared to the clades with only symmetric meiosis. However, despite the impression one might get from the literature, this key prediction of the centromere drive model has not only never been confirmed, but it has never been tested, because all the previous studies dealt only with the presence or absence instead of the frequency of positive selection. To provide evidence for or against different frequencies of positively selected CenH3 in asymmetrics and symmetrics, we have inferred the selective pressures acting on CenH3 in seventeen eukaryotic clades, including plants, animals, fungi, ciliates and apicomplexa, using codon-substitution models, and compared the inferred frequencies between asymmetrics and symmetrics in a quantitative manner. We have found that CenH3 has been evolving adaptively much more frequently in clades with asymmetric meiosis compared with clades displaying only symmetric meiosis which confirms the prediction of centromere drive model. Our findings indicate that the evolution of asymmetric meiosis required CenH3 to evolve adaptively more often to counterbalance the negative consequences of centromere drive.

  4. Transcriptome of Aphanomyces euteiches: new oomycete putative pathogenicity factors and metabolic pathways.

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    Elodie Gaulin

    Full Text Available Aphanomyces euteiches is an oomycete pathogen that causes seedling blight and root rot of legumes, such as alfalfa and pea. The genus Aphanomyces is phylogenically distinct from well-studied oomycetes such as Phytophthora sp., and contains species pathogenic on plants and aquatic animals. To provide the first foray into gene diversity of A. euteiches, two cDNA libraries were constructed using mRNA extracted from mycelium grown in an artificial liquid medium or in contact to plant roots. A unigene set of 7,977 sequences was obtained from 18,864 high-quality expressed sequenced tags (ESTs and characterized for potential functions. Comparisons with oomycete proteomes revealed major differences between the gene content of A. euteiches and those of Phytophthora species, leading to the identification of biosynthetic pathways absent in Phytophthora, of new putative pathogenicity genes and of expansion of gene families encoding extracellular proteins, notably different classes of proteases. Among the genes specific of A. euteiches are members of a new family of extracellular proteins putatively involved in adhesion, containing up to four protein domains similar to fungal cellulose binding domains. Comparison of A. euteiches sequences with proteomes of fully sequenced eukaryotic pathogens, including fungi, apicomplexa and trypanosomatids, allowed the identification of A. euteiches genes with close orthologs in these microorganisms but absent in other oomycetes sequenced so far, notably transporters and non-ribosomal peptide synthetases, and suggests the presence of a defense mechanism against oxidative stress which was initially characterized in the pathogenic trypanosomatids.

  5. [Serological survey of animal toxoplasmosis in Senegal].

    Science.gov (United States)

    Davoust, B; Mediannikov, O; Roqueplo, C; Perret, C; Demoncheaux, J-P; Sambou, M; Guillot, J; Blaga, R

    2015-02-01

    Toxoplasma gondii is an obligate, intracellular, parasitic protozoan within the phylum Apicomplexa that causes toxoplasmosis in mammalian hosts (including humans) and birds. We used modified direct agglutination test for the screening of the animals' sera collected in Senegal. In total, 419 animals' sera have been studied: 103 bovines, 43 sheep, 52 goats, 63 horses, 13 donkeys and 145 dogs. The collection of sera was performed in four different regions of Senegal: Dakar, Sine Saloum, Kedougou and Basse Casamance from 2011 to 2013. We have revealed antibodies in 13% of bovines, 16% of sheep, 15% of goats, 30% of horses, 23% of donkeys and 67% of dogs. Private dogs from villages were more often to have the anti-Toxoplasma antibodies compared to security society-owned dogs from Dakar. It may be explained by different meal consumed by dogs (factory-produced meal for dogs from Dakar vs. irregular sources for village dogs). Intense circulation of T. gondii in the studied zone may explain the unusually high seroprevalence among horses and donkeys. Tropical climate with high temperature and humidity is favorable for the conservation of oocysts of T. gondii. Results presented here may contribute to the evaluation of the risks of toxoplasmosis in humans in Senegal.

  6. Nuclear actin-related protein is required for chromosome segregation in Toxoplasma gondii.

    Science.gov (United States)

    Suvorova, Elena S; Lehmann, Margaret M; Kratzer, Stella; White, Michael W

    2012-01-01

    Apicomplexa parasites use complex cell cycles to replicate that are not well understood mechanistically. We have established a robust forward genetic strategy to identify the essential components of parasite cell division. Here we describe a novel temperature sensitive Toxoplasma strain, mutant 13-20C2, which growth arrests due to a defect in mitosis. The primary phenotype is the mis-segregation of duplicated chromosomes with chromosome loss during nuclear division. This defect is conditional-lethal with respect to temperature, although relatively mild in regard to the preservation of the major microtubule organizing centers. Despite severe DNA loss many of the physical structures associated with daughter budding and the assembly of invasion structures formed and operated normally at the non-permissive temperature before completely arresting. These results suggest there are coordinating mechanisms that govern the timing of these events in the parasite cell cycle. The defect in mutant 13-20C2 was mapped by genetic complementation to Toxoplasma chromosome III and to a specific mutation in the gene encoding an ortholog of nuclear actin-related protein 4. A change in a conserved isoleucine to threonine in the helical structure of this nuclear actin related protein leads to protein instability and cellular mis-localization at the higher temperature. Given the age of this protist family, the results indicate a key role for nuclear actin-related proteins in chromosome segregation was established very early in the evolution of eukaryotes.

  7. Population Abundance of Potentially Pathogenic Organisms in Intestinal Microbiome of Jungle Crow (Corvus macrorhynchos Shown with 16S rRNA Gene-Based Microbial Community Analysis

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    Isamu Maeda

    2013-01-01

    Full Text Available Jungle Crows (Corvus macrorhynchos prefer human habitats because of their versatility in feeding accompanied with human food consumption. Therefore, it is important from a public health viewpoint to characterize their intestinal microbiota. However, no studies have been involved in molecular characterization of the microbiota based on huge and reliable number of data acquisition. In this study, 16S rRNA gene-based microbial community analysis coupled with the next-generation DNA sequencing techniques was applied to the taxonomic classification of intestinal microbiome for three jungle crows. Clustering of the reads into 130 operational taxonomic units showed that at least 70% of analyzed sequences for each crow were highly homologous to Eimeria sp., which belongs to the protozoan phylum Apicomplexa. The microbiotas of three crows also contained potentially pathogenic bacteria with significant percentages, such as the genera Campylobacter and Brachyspira. Thus, the profiling of a large number of 16S rRNA gene sequences in crow intestinal microbiomes revealed the high-frequency existence or vestige of potentially pathogenic microorganisms.

  8. Detection of Babesia divergens in southern Norway by using an immunofluorescence antibody test in cow sera

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    Røed Knut H

    2010-10-01

    Full Text Available Abstract Background The incidence of bovine babesiosis, caused by Babesia divergens (Apicomplexa: Piroplasmida has decreased markedly since the 1930 s, but may re-emerge as a consequence of climate change and changes in legislation and pasturing practices. This is a potentially serious disease, with both economical and animal welfare consequences. Therefore, there is a need to survey the distribution of B. divergens. Methods We tested sera from 306 healthy pastured cows from 24 farms along the southern Norwegian coast by using an indirect immunofluorescence IgG antibody test (IFAT. Fractions of seropositive cows were compared by calculating 95% CI. Results The results of this test showed that 27% of the sera were positive for B. divergens antibodies. The fraction of antibody-positive sera that we detected showed a two-humped distribution, with a high fraction of positives being found in municipalities in the western and eastern parts of the study area, while the municipalities between these areas had few or no positive serum samples. Conclusions Neither the farmers' observations nor the Norwegian Dairy Herd Recording System give an adequate picture of the distribution of bovine babesiosis. Serological testing of cows by using IFAT is a convenient way of screening for the presence of B. divergens in an area.

  9. The life cycle of Gregarina cuneata in the midgut of Tribolium castaneum and the effects of parasitism on the development of insects.

    Science.gov (United States)

    Gigliolli, A A S; Julio, A H F; Conte, H

    2016-04-01

    Tribolium castaneum Herbst 1797 (Coleoptera: Tenebrionidae), an important pest of stored grains and byproducts, is naturally infected by Gregarina cuneata Stein 1848 (Apicomplexa: Gregarinidae). Changes in the life cycle of insects caused by the parasite development in the midgut were studied. Trophozoites, gamonts (solitary and associated), and gametocysts were present in the midgut of the insects. In young trophozoites, the apical region differentiated into an epimerite that firmly attached the parasite to the host epithelial cells. With maturation, trophozoites developed in gamonts that were associated with the initiation of sexual reproduction in the cell cycle, culminating in the formation of the spherical gametocyst. Morpho-functional analyses indicated that gregarines absorb nutrients from infected cells and can occlude the midgut as they develop. Consequently, nutritional depletion may interfere with the host's physiology, causing decreased growth, delayed development, and high mortality rates of the parasitized insects. These results suggest G. cuneata could be an important biological agent for controlling T. castaneum in integrated pest management programs.

  10. Theileria parasites secrete a prolyl isomerase to maintain host leukocyte transformation.

    Science.gov (United States)

    Marsolier, J; Perichon, M; DeBarry, J D; Villoutreix, B O; Chluba, J; Lopez, T; Garrido, C; Zhou, X Z; Lu, K P; Fritsch, L; Ait-Si-Ali, S; Mhadhbi, M; Medjkane, S; Weitzman, J B

    2015-04-16

    Infectious agents develop intricate mechanisms to interact with host cell pathways and hijack their genetic and epigenetic machinery to change host cell phenotypic states. Among the Apicomplexa phylum of obligate intracellular parasites, which cause veterinary and human diseases, Theileria is the only genus that transforms its mammalian host cells. Theileria infection of bovine leukocytes induces proliferative and invasive phenotypes associated with activated signalling pathways, notably JNK and AP-1 (ref. 2). The transformed phenotypes are reversed by treatment with the theilericidal drug buparvaquone. We used comparative genomics to identify a homologue of the peptidyl-prolyl isomerase PIN1 in T. annulata (TaPIN1) that is secreted into the host cell and modulates oncogenic signalling pathways. Here we show that TaPIN1 is a bona fide prolyl isomerase and that it interacts with the host ubiquitin ligase FBW7, leading to its degradation and subsequent stabilization of c-JUN, which promotes transformation. We performed in vitro and in silico analysis and in vivo zebrafish xenograft experiments to demonstrate that TaPIN1 is directly inhibited by the anti-parasite drug buparvaquone (and other known PIN1 inhibitors) and is mutated in a drug-resistant strain. Prolyl isomerization is thus a conserved mechanism that is important in cancer and is used by Theileria parasites to manipulate host oncogenic signalling.

  11. Three-dimensional visualisation of developmental stages of an apicomplexan fish blood parasite in its invertebrate host

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    Hayes Polly M

    2011-11-01

    Full Text Available Abstract Background Although widely used in medicine, the application of three-dimensional (3D imaging to parasitology appears limited to date. In this study, developmental stages of a marine fish haemogregarine, Haemogregarina curvata (Apicomplexa: Adeleorina, were investigated in their leech vector, Zeylanicobdella arugamensis; this involved 3D visualisation of brightfield and confocal microscopy images of histological sections through infected leech salivary gland cells. Findings 3D assessment demonstrated the morphology of the haemogregarine stages, their spatial layout, and their relationship with enlarged host cells showing reduced cellular content. Haemogregarine meronts, located marginally within leech salivary gland cells, had small tail-like connections to the host cell limiting membrane; this parasite-host cell interface was not visible in two-dimensional (2D light micrographs and no records of a similar connection in apicomplexan development have been traced. Conclusions This is likely the first account of the use of 3D visualisation to study developmental stages of an apicomplexan parasite in its invertebrate vector. Elucidation of the extent of development of the haemogregarine within the leech salivary cells, together with the unusual connections between meronts and the host cell membrane, illustrates the future potential of 3D visualisation in parasite-vector biology.

  12. Intravacuolar Membranes Regulate CD8 T Cell Recognition of Membrane-Bound Toxoplasma gondii Protective Antigen

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    Jodie Lopez

    2015-12-01

    Full Text Available Apicomplexa parasites such as Toxoplasma gondii target effectors to and across the boundary of their parasitophorous vacuole (PV, resulting in host cell subversion and potential presentation by MHC class I molecules for CD8 T cell recognition. The host-parasite interface comprises the PV limiting membrane and a highly curved, membranous intravacuolar network (IVN of uncertain function. Here, using a cell-free minimal system, we dissect how membrane tubules are shaped by the parasite effectors GRA2 and GRA6. We show that membrane association regulates access of the GRA6 protective antigen to the MHC I pathway in infected cells. Although insertion of GRA6 in the PV membrane is key for immunogenicity, association of GRA6 with the IVN limits presentation and curtails GRA6-specific CD8 responses in mice. Thus, membrane deformations of the PV regulate access of antigens to the MHC class I pathway, and the IVN may play a role in immune modulation.

  13. [Human babesiosis - a rare but potentially dangerous zoonosis].

    Science.gov (United States)

    Hildebrandt, A; Hunfeld, K-P

    2014-05-01

    Human babesiosis is caused by the intraerythrocytic parasite of the genus Babesia (phylum Apicomplexa). Humans are commonly infected by the bite of Ixodid ticks. Rarely, transmission does occur perinatal or via contaminated blood transfusion. There is only insufficient data available on the clinical relevance in Europe, whereas there are known endemic states in the United States with an increasing importance of the disease in transfusion medicine. The following article gives an overview of the situation in Germany. Human babesiosis is a zoonotic disease with a worldwide increasing importance according to the increasing number of immunocompromised patients. Clinical symptoms have a wide range from asymptomatic to severe and letal cases. So far, the detection of the parasites in ticks and seroepidemiological data in Europe identified 3 humanpathogenic species: B. microti, B. divergens und B. venatorum (EU1-3). The relative small number of approximately 50 documented human cases is probably due to the lack of knowledge of the disease and the availability of diagnostic tools. Comprehensive systematic investigations of the prevalence in ticks, seroepidemiological data and improved diagnostic tests are urgently needed to evaluate the importance of the parasite.

  14. Comparison of an ELISA assay for the detection of adhesive/invasive Neospora caninum tachyzoites

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    Luiz Miguel Pereira

    Full Text Available Neospora caninum belongs to the phylum Apicomplexa, the causative agent of neosporosis, which leads to economic impacts on cattle production. A common feature among apicomplexan parasites is the invasive process driven mostly by the parasite. As a first evaluation of candidate molecules that play a possible role by interfering in this invasive process, the in vitro invasion assay is a fast and direct way to screen future agonists or antagonists. This work involved the development of a new cell culture ELISA and transient β-galactosidase activity applied to the semi-quantitative detection of N. caninum in Vero cell culture. Cell culture ELISA is based on histochemistry and immunology, resulting in a colorimetric reaction. The β-galactosidase activity was obtained by the transient transfection of the lacZ gene under control of RPS13 promoter of N. caninum. These methods were used to evaluate the effects of temperature (37°C and 85°C on the invasion and adhesion of tachyzoites. The three tested methods (real time PCR, β-galactosidase activity and ELISA showed a similar pattern, indicating that different methods may be complementary.

  15. Phylogeny and evolution of apicoplasts and apicomplexan parasites.

    Science.gov (United States)

    Arisue, Nobuko; Hashimoto, Tetsuo

    2015-06-01

    The phylum Apicomplexa includes many parasitic genera of medical and veterinary importance including Plasmodium (causative agent of malaria), Toxoplasma (toxoplasmosis), and Babesia (babesiosis). Most of the apicomplexan parasites possess a unique, essential organelle, the apicoplast, which is a plastid without photosynthetic ability. Although the apicoplast is considered to have evolved through secondary endosymbiosis of a red alga into the common ancestral cell of apicomplexans, its evolutionary history has been under debate until recently. The apicoplast has a genome around 30-40 kb in length. Repertoire and arrangement of the apicoplast genome-encoded genes differ among apicomplexan genera, although within the genus Plasmodium these are almost conserved. Genes in the apicoplast genome may be useful markers for Plasmodium phylogeny, because these are single copy (except for the inverted repeat region) and may have more phylogenetic signal than the mitochondrial genome that have been most commonly used for Plasmodium phylogeny. This review describes recent studies concerning the evolutionary origin of the apicoplast, presents evolutionary comparison of the primary structures of apicoplast genomes from apicomplexan parasites, and summarizes recent findings of malaria phylogeny based on apicoplast genome-encoded genes.

  16. 巴贝斯虫感染对宿主红细胞及免疫系统的影响%INFLUENCE OF BABESIA INFECTION ON HOST ERYTHROCYTES AND IMMUNE SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    魏金龙; 周金林

    2015-01-01

    巴贝斯虫(Babesia)是一种寄生于宿主红细胞的顶复门寄生虫,硬蜱为其传播媒介。由于巴贝斯虫感染后可以引起人或动物严重的临床症状,甚至造成死亡,给畜牧业和人类健康带来了极大威胁。本文主要综合国内外近年的研究成果,从巴贝斯虫入侵红细胞并对红细胞造成的影响,宿主感染后机体免疫状态的变化,以及共感染等方面进行综述,旨在为巴贝斯虫相关研究提供参考。%Babesia parasites are tick-transmitted intraerythrocytic protozoa of the phylum Apicomplexa, causing severe and even fatal disease and posing a great threaten for animal husbandry and human health. In this article, parasitic invasion to erythrocytes, changes of the host immune status after infection and aspects of co-infection are summarized according to the published results up to date. which will provide a reference for Babesia research.

  17. Prevalence of Protozoa Species in Drinking and Environmental Water Sources in Sudan

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    Salah Shanan

    2015-01-01

    Full Text Available Protozoa are eukaryotic cells distributed worldwide in nature and are receiving increasing attention as reservoirs and potential vectors for the transmission of pathogenic bacteria. In the environment, on the other hand, many genera of the protozoa are human and animal pathogens. Only limited information is available on these organisms in developing countries and so far no information on their presence is available from Sudan. It is necessary to establish a molecular identification of species of the protozoa from drinking and environmental water. 600 water samples were collected from five states (Gadarif, Khartoum, Kordofan, Juba, and Wad Madani in Sudan and analysed by polymerase chain reaction (PCR and sequencing. 57 out of 600 water samples were PCR positive for protozoa. 38 out of the 57 positive samples were identified by sequencing to contain 66 protozoa species including 19 (28.8% amoebae, 17 (25.7% Apicomplexa, 25 (37.9% ciliates, and 5 (7.6% flagellates. This study utilized molecular methods identified species belonging to all phyla of protozoa and presented a fast and accurate molecular detection and identification of pathogenic as well as free-living protozoa in water uncovering hazards facing public health.

  18. PRODUÇÃO DE HIBRIDOMAS SECRETORES DE ANTICORPOS ANTI- Neospora caninum PARA USO EM IMUNODIAGNÓSTICO

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    Bruna Alves Devens

    2014-06-01

    Full Text Available The Neospora caninum is a protozoan Apicomplexa with greater involvement in abortions worldwide. The economic losses determined by neosporosis also include abortions besides the early disposal of cows, costs for replacing animals in the herd, drop in milk production as well as milk in fat production. The immunological diagnosis involves purchasing costly diagnostic kits on the market. Therefore, the aim of this study was the production of hybridomas secreting polyclonal antibodies with affinity to Neospora caninum (Nc-1 strain for immunodiagnostic use. For antibodies production, we used sonicated protozoa from Vero cells in culture, purified by filtration. These tachyzoites were employed for immunization of BALB / c mice using saponin as adjuvant, which allowed obtaining polyclonal antibodies capable of revealing fluorescein reaction in indirect immunofluorescence. The fusion of splenic cells, from the immunized mice with myeloma cells SP2 / 0 resulted in 72.4% hybridomas secreting anti-Nc-1antibodies. These hybridomas secreted antibodies positive to N. caninum and negative to Toxoplasma gondii.

  19. Prevalence of protozoa species in drinking and environmental water sources in Sudan.

    Science.gov (United States)

    Shanan, Salah; Abd, Hadi; Bayoumi, Magdi; Saeed, Amir; Sandström, Gunnar

    2015-01-01

    Protozoa are eukaryotic cells distributed worldwide in nature and are receiving increasing attention as reservoirs and potential vectors for the transmission of pathogenic bacteria. In the environment, on the other hand, many genera of the protozoa are human and animal pathogens. Only limited information is available on these organisms in developing countries and so far no information on their presence is available from Sudan. It is necessary to establish a molecular identification of species of the protozoa from drinking and environmental water. 600 water samples were collected from five states (Gadarif, Khartoum, Kordofan, Juba, and Wad Madani) in Sudan and analysed by polymerase chain reaction (PCR) and sequencing. 57 out of 600 water samples were PCR positive for protozoa. 38 out of the 57 positive samples were identified by sequencing to contain 66 protozoa species including 19 (28.8%) amoebae, 17 (25.7%) Apicomplexa, 25 (37.9%) ciliates, and 5 (7.6%) flagellates. This study utilized molecular methods identified species belonging to all phyla of protozoa and presented a fast and accurate molecular detection and identification of pathogenic as well as free-living protozoa in water uncovering hazards facing public health.

  20. Unique apicomplexan IMC sub-compartment proteins are early markers for apical polarity in the malaria parasite.

    Science.gov (United States)

    Poulin, Benoit; Patzewitz, Eva-Maria; Brady, Declan; Silvie, Olivier; Wright, Megan H; Ferguson, David J P; Wall, Richard J; Whipple, Sarah; Guttery, David S; Tate, Edward W; Wickstead, Bill; Holder, Anthony A; Tewari, Rita

    2013-01-01

    The phylum Apicomplexa comprises over 5000 intracellular protozoan parasites, including Plasmodium and Toxoplasma, that are clinically important pathogens affecting humans and livestock. Malaria parasites belonging to the genus Plasmodium possess a pellicle comprised of a plasmalemma and inner membrane complex (IMC), which is implicated in parasite motility and invasion. Using live cell imaging and reverse genetics in the rodent malaria model P. berghei, we localise two unique IMC sub-compartment proteins (ISPs) and examine their role in defining apical polarity during zygote (ookinete) development. We show that these proteins localise to the anterior apical end of the parasite where IMC organisation is initiated, and are expressed at all developmental stages, especially those that are invasive. Both ISP proteins are N-myristoylated, phosphorylated and membrane-bound. Gene disruption studies suggest that ISP1 is likely essential for parasite development, whereas ISP3 is not. However, an absence of ISP3 alters the apical localisation of ISP1 in all invasive stages including ookinetes and sporozoites, suggesting a coordinated function for these proteins in the organisation of apical polarity in the parasite.

  1. Purification, crystallization and preliminary X-ray diffraction analysis of inner membrane complex (IMC) subcompartment protein 1 (ISP1) from Toxoplasma gondii.

    Science.gov (United States)

    Tonkin, Michelle L; Brown, Shannon; Beck, Josh R; Bradley, Peter J; Boulanger, Martin J

    2012-07-01

    The protozoan parasites of the Apicomplexa phylum are devastating global pathogens. Their success is largely due to phylum-specific proteins found in specialized organelles and cellular structures. The inner membrane complex (IMC) is a unique apicomplexan structure that is essential for motility, invasion and replication. The IMC subcompartment proteins (ISP) have recently been identified in Toxoplasma gondii and shown to be critical for replication, although their specific mechanisms are unknown. Structural characterization of TgISP1 was pursued in order to identify the fold adopted by the ISPs and to generate detailed insight into how this family of proteins functions during replication. An N-terminally truncated form of TgISP1 was purified from Escherichia coli, crystallized and subjected to X-ray diffraction analysis. Two crystal forms of TgISP1 belonging to space groups P4(1)32 or P4(3)32 and P2(1)2(1)2(1) diffracted to 2.05 and 2.1 Å resolution, respectively.

  2. A novel family of Toxoplasma IMC proteins displays a hierarchical organization and functions in coordinating parasite division.

    Science.gov (United States)

    Beck, Josh R; Rodriguez-Fernandez, Imilce A; de Leon, Jessica Cruz; Huynh, My-Hang; Carruthers, Vern B; Morrissette, Naomi S; Bradley, Peter J

    2010-09-09

    Apicomplexans employ a peripheral membrane system called the inner membrane complex (IMC) for critical processes such as host cell invasion and daughter cell formation. We have identified a family of proteins that define novel sub-compartments of the Toxoplasma gondii IMC. These IMC Sub-compartment Proteins, ISP1, 2 and 3, are conserved throughout the Apicomplexa, but do not appear to be present outside the phylum. ISP1 localizes to the apical cap portion of the IMC, while ISP2 localizes to a central IMC region and ISP3 localizes to a central plus basal region of the complex. Targeting of all three ISPs is dependent upon N-terminal residues predicted for coordinated myristoylation and palmitoylation. Surprisingly, we show that disruption of ISP1 results in a dramatic relocalization of ISP2 and ISP3 to the apical cap. Although the N-terminal region of ISP1 is necessary and sufficient for apical cap targeting, exclusion of other family members requires the remaining C-terminal region of the protein. This gate-keeping function of ISP1 reveals an unprecedented mechanism of interactive and hierarchical targeting of proteins to establish these unique sub-compartments in the Toxoplasma IMC. Finally, we show that loss of ISP2 results in severe defects in daughter cell formation during endodyogeny, indicating a role for the ISP proteins in coordinating this unique process of Toxoplasma replication.

  3. Parasites of the mangrove mussel Mytella guyanensis (Bivalvia: Mytilidae in Camamu Bay, Bahia, Brazil

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    LO. Ceuta

    Full Text Available This contribution reports the parasites found in the mangrove mussel Mytella guyanensis in Camamu Bay, Bahia, Brazil. Samples were collected monthly from September 2006 through October 2007. A total of 460 individuals were collected, fixed in Davidson's solution, and processed by standard histological techniques, and the sections were stained with Harris hematoxylin and eosin (H&E. The water temperature ranged from 23.5 to 31.6 ºC, and the salinity from 25 to 37‰. Microscopic analysis showed Rickettsia-like organisms (RLOs, Nematopsis sp. (Apicomplexa, and Platyhelminthes, including a turbellarian, sporocysts of Bucephalus sp., metacercariae, and metacestodes of Tylocephalum sp. Parasites were observed mainly in the gills, mantle, and digestive gland. The prevalence of Nematopsis sp. was 100%, and in heavily infected mussels the tissues of the labial palps were damaged. RLOs occurred in high prevalence and intensity of infection in some periods. The digenean sporocysts showed moderate prevalence but high intensity of infection, and caused parasitic castration. In general, there was no significant spatial or temporal variation (p > 0.05 of the parasites, which is probably attributable to the small variations of temperature and salinity in the region.

  4. Composite genome map and recombination parameters derived from three archetypal lineages of Toxoplasma gondii

    Science.gov (United States)

    Khan, Asis; Taylor, Sonya; Su, Chunlei; Mackey, Aaron J.; Boyle, Jon; Cole, Robert; Glover, Darius; Tang, Keliang; Paulsen, Ian T.; Berriman, Matt; Boothroyd, John C.; Pfefferkorn, Elmer R.; Dubey, J. P.; Ajioka, James W.; Roos, David S.; Wootton, John C.; Sibley, L. David

    2005-01-01

    Toxoplasma gondii is a highly successful protozoan parasite in the phylum Apicomplexa, which contains numerous animal and human pathogens. T.gondii is amenable to cellular, biochemical, molecular and genetic studies, making it a model for the biology of this important group of parasites. To facilitate forward genetic analysis, we have developed a high-resolution genetic linkage map for T.gondii. The genetic map was used to assemble the scaffolds from a 10X shotgun whole genome sequence, thus defining 14 chromosomes with markers spaced at ∼300 kb intervals across the genome. Fourteen chromosomes were identified comprising a total genetic size of ∼592 cM and an average map unit of ∼104 kb/cM. Analysis of the genetic parameters in T.gondii revealed a high frequency of closely adjacent, apparent double crossover events that may represent gene conversions. In addition, we detected large regions of genetic homogeneity among the archetypal clonal lineages, reflecting the relatively few genetic outbreeding events that have occurred since their recent origin. Despite these unusual features, linkage analysis proved to be effective in mapping the loci determining several drug resistances. The resulting genome map provides a framework for analysis of complex traits such as virulence and transmission, and for comparative population genetic studies. PMID:15911631

  5. Flavonoids modulate the proliferation of Neospora caninum in glial cell primary cultures.

    Science.gov (United States)

    Matos, Rosan Barbosa de; Braga-de-Souza, Suzana; Pitanga, Bruno Pena Seara; Silva, Victor Diógenes Amaral da; Jesus, Erica Etelvina Viana de; Pinheiro, Alexandre Morales; Costa, Maria de Fátima Dias; El-Bacha, Ramon dos Santos; Ribeiro, Cátia Suse de Oliveira; Costa, Silvia Lima

    2014-12-01

    Neospora caninum (Apicomplexa; Sarcocystidae) is a protozoan that causes abortion in cattle, horses, sheep, and dogs as well as neurological and dermatological diseases in dogs. In the central nervous system of dogs infected with N. caninum, cysts were detected that exhibited gliosis and meningitis. Flavonoids are polyphenolic compounds that exhibit antibacterial, antiparasitic, antifungal, and antiviral properties. In this study, we investigated the effects of flavonoids in a well-established in vitro model of N. caninum infection in glial cell cultures. Glial cells were treated individually with 10 different flavonoids, and a subset of cultures was also infected with the NC-1 strain of N. caninum. All of the flavonoids tested induced an increase in the metabolism of glial cells and many of them increased nitrite levels in cultures infected with NC-1 compared to controls and uninfected cultures. Among the flavonoids tested, 3',4'-dihydroxyflavone, 3',4',5,7-tetrahydroxyflavone (luteolin), and 3,3',4',5,6-pentahydroxyflavone (quercetin), also inhibited parasitophorous vacuole formation. Taken together, our findings show that flavonoids modulate glial cell responses, increase NO secretion, and interfere with N. caninum infection and proliferation.

  6. Comparison of an ELISA assay for the detection of adhesive/invasive Neospora caninum tachyzoites.

    Science.gov (United States)

    Pereira, Luiz Miguel; Yatsuda, Ana Patrícia

    2014-03-01

    Neospora caninum belongs to the phylum Apicomplexa, the causative agent of neosporosis, which leads to economic impacts on cattle production. A common feature among apicomplexan parasites is the invasive process driven mostly by the parasite. As a first evaluation of candidate molecules that play a possible role by interfering in this invasive process, the in vitro invasion assay is a fast and direct way to screen future agonists or antagonists. This work involved the development of a new cell culture ELISA and transient β-galactosidase activity applied to the semi-quantitative detection of N. caninum in Vero cell culture. Cell culture ELISA is based on histochemistry and immunology, resulting in a colorimetric reaction. The β-galactosidase activity was obtained by the transient transfection of the lacZ gene under control of RPS13 promoter of N. caninum. These methods were used to evaluate the effects of temperature (37°C and 85°C) on the invasion and adhesion of tachyzoites. The three tested methods (real time PCR, β-galactosidase activity and ELISA) showed a similar pattern, indicating that different methods may be complementary.

  7. The chloramphenicol acetyltransferase vector as a tool for stable tagging of Neospora caninum.

    Science.gov (United States)

    Pereira, Luiz Miguel; Yatsuda, Ana Patrícia

    2014-09-01

    Neospora caninum is an obligate intracellular Apicomplexa, a phylum where one of the current methods for functional studies relies on molecular genetic tools. For Toxoplasma gondii, the first method described, in 1993, was based on resistance against chloramphenicol. As in T. gondii, we developed a vector constituted of the chloramphenicol acetyltransferase gene (CAT) flanked by the N. caninum dihydrofolate reductase-thymidylate synthase (DHFR-TS) 5' coding sequence flanking region. Five weeks after transfection and under the selection of chloramphenicol the expression of CAT increased compared to the wild type and the resistance was retained for more than one year. Between the stop codon of CAT and the 3' UTR of DHFR, a Lac-Z gene controlled by the N. caninum tubulin 5' coding sequence flanking region was ligated, resulting in a vector with a reporter gene (Ncdhfr-CAT/NcTub-tetO/Lac-Z). The stability was maintained through an episomal pattern for 14 months when the tachyzoites succumbed, which was an unexpected phenomenon compared to T. gondii. Stable parasites expressing the Lac-Z gene allowed the detection of tachyzoites after invasion by enzymatic reaction (CPRG) and were visualised macro- and microscopically by X-Gal precipitation and fluorescence. This work developed the first vector for stable expression of proteins based on chloramphenicol resistance and controlled exclusively by N. caninum promoters.

  8. Amplicon-Based Pyrosequencing Reveals High Diversity of Protistan Parasites in Ships' Ballast Water: Implications for Biogeography and Infectious Diseases.

    Science.gov (United States)

    Pagenkopp Lohan, K M; Fleischer, R C; Carney, K J; Holzer, K K; Ruiz, G M

    2016-04-01

    Ships' ballast water (BW) commonly moves macroorganisms and microorganisms across the world's oceans and along coasts; however, the majority of these microbial transfers have gone undetected. We applied high-throughput sequencing methods to identify microbial eukaryotes, specifically emphasizing the protistan parasites, in ships' BW collected from vessels calling to the Chesapeake Bay (Virginia and Maryland, USA) from European and Eastern Canadian ports. We utilized tagged-amplicon 454 pyrosequencing with two general primer sets, amplifying either the V4 or V9 domain of the small subunit (SSU) of the ribosomal RNA (rRNA) gene complex, from total DNA extracted from water samples collected from the ballast tanks of bulk cargo vessels. We detected a diverse group of protistan taxa, with some known to contain important parasites in marine systems, including Apicomplexa (unidentified apicomplexans, unidentified gregarines, Cryptosporidium spp.), Dinophyta (Blastodinium spp., Euduboscquella sp., unidentified syndinids, Karlodinium spp., Syndinium spp.), Perkinsea (Parvilucifera sp.), Opisthokonta (Ichthyosporea sp., Pseudoperkinsidae, unidentified ichthyosporeans), and Stramenopiles (Labyrinthulomycetes). Further characterization of groups with parasitic taxa, consisting of phylogenetic analyses for four taxa (Cryptosporidium spp., Parvilucifera spp., Labyrinthulomycetes, and Ichthyosporea), revealed that sequences were obtained from both known and novel lineages. This study demonstrates that high-throughput sequencing is a viable and sensitive method for detecting parasitic protists when present and transported in the ballast water of ships. These data also underscore the potential importance of human-aided dispersal in the biogeography of these microbes and emerging diseases in the world's oceans.

  9. Chromerid genomes reveal the evolutionary path from photosynthetic algae to obligate intracellular parasites

    KAUST Repository

    Woo, Yong

    2015-07-15

    The eukaryotic phylum Apicomplexa encompasses thousands of obligate intracellular parasites of humans and animals with immense socio-economic and health impacts. We sequenced nuclear genomes of Chromera velia and Vitrella brassicaformis, free-living non-parasitic photosynthetic algae closely related to apicomplexans. Proteins from key metabolic pathways and from the endomembrane trafficking systems associated with a free-living lifestyle have been progressively and non-randomly lost during adaptation to parasitism. The free-living ancestor contained a broad repertoire of genes many of which were repurposed for parasitic processes, such as extracellular proteins, components of a motility apparatus, and DNA- and RNA-binding protein families. Based on transcriptome analyses across 36 environmental conditions, Chromera orthologs of apicomplexan invasion-related motility genes were co-regulated with genes encoding the flagellar apparatus, supporting the functional contribution of flagella to the evolution of invasion machinery. This study provides insights into how obligate parasites with diverse life strategies arose from a once free-living phototrophic marine alga. © Woo et al.

  10. A novel family of Toxoplasma IMC proteins displays a hierarchical organization and functions in coordinating parasite division.

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    Josh R Beck

    Full Text Available Apicomplexans employ a peripheral membrane system called the inner membrane complex (IMC for critical processes such as host cell invasion and daughter cell formation. We have identified a family of proteins that define novel sub-compartments of the Toxoplasma gondii IMC. These IMC Sub-compartment Proteins, ISP1, 2 and 3, are conserved throughout the Apicomplexa, but do not appear to be present outside the phylum. ISP1 localizes to the apical cap portion of the IMC, while ISP2 localizes to a central IMC region and ISP3 localizes to a central plus basal region of the complex. Targeting of all three ISPs is dependent upon N-terminal residues predicted for coordinated myristoylation and palmitoylation. Surprisingly, we show that disruption of ISP1 results in a dramatic relocalization of ISP2 and ISP3 to the apical cap. Although the N-terminal region of ISP1 is necessary and sufficient for apical cap targeting, exclusion of other family members requires the remaining C-terminal region of the protein. This gate-keeping function of ISP1 reveals an unprecedented mechanism of interactive and hierarchical targeting of proteins to establish these unique sub-compartments in the Toxoplasma IMC. Finally, we show that loss of ISP2 results in severe defects in daughter cell formation during endodyogeny, indicating a role for the ISP proteins in coordinating this unique process of Toxoplasma replication.

  11. Unique apicomplexan IMC sub-compartment proteins are early markers for apical polarity in the malaria parasite

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    Benoit Poulin

    2013-09-01

    The phylum Apicomplexa comprises over 5000 intracellular protozoan parasites, including Plasmodium and Toxoplasma, that are clinically important pathogens affecting humans and livestock. Malaria parasites belonging to the genus Plasmodium possess a pellicle comprised of a plasmalemma and inner membrane complex (IMC, which is implicated in parasite motility and invasion. Using live cell imaging and reverse genetics in the rodent malaria model P. berghei, we localise two unique IMC sub-compartment proteins (ISPs and examine their role in defining apical polarity during zygote (ookinete development. We show that these proteins localise to the anterior apical end of the parasite where IMC organisation is initiated, and are expressed at all developmental stages, especially those that are invasive. Both ISP proteins are N-myristoylated, phosphorylated and membrane-bound. Gene disruption studies suggest that ISP1 is likely essential for parasite development, whereas ISP3 is not. However, an absence of ISP3 alters the apical localisation of ISP1 in all invasive stages including ookinetes and sporozoites, suggesting a coordinated function for these proteins in the organisation of apical polarity in the parasite.

  12. Putative monofunctional type I polyketide synthase units: a dinoflagellate-specific feature?

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    Karsten Eichholz

    Full Text Available Marine dinoflagellates (alveolata are microalgae of which some cause harmful algal blooms and produce a broad variety of most likely polyketide synthesis derived phycotoxins. Recently, novel polyketide synthesase (PKS transcripts have been described from the Florida red tide dinoflagellate Karenia brevis (gymnodiniales which are evolutionarily related to Type I PKS but were apparently expressed as monofunctional proteins, a feature typical of Type II PKS. Here, we investigated expression units of PKS I-like sequences in Alexandrium ostenfeldii (gonyaulacales and Heterocapsa triquetra (peridiniales at the transcript and protein level. The five full length transcripts we obtained were all characterized by polyadenylation, a 3' UTR and the dinoflagellate specific spliced leader sequence at the 5'end. Each of the five transcripts encoded a single ketoacylsynthase (KS domain showing high similarity to K. brevis KS sequences. The monofunctional structure was also confirmed using dinoflagellate specific KS antibodies in Western Blots. In a maximum likelihood phylogenetic analysis of KS domains from diverse PKSs, dinoflagellate KSs formed a clade placed well within the protist Type I PKS clade between apicomplexa, haptophytes and chlorophytes. These findings indicate that the atypical PKS I structure, i.e., expression as putative monofunctional units, might be a dinoflagellate specific feature. In addition, the sequenced transcripts harbored a previously unknown, apparently dinoflagellate specific conserved N-terminal domain. We discuss the implications of this novel region with regard to the putative monofunctional organization of Type I PKS in dinoflagellates.

  13. Mechanisms of invasion from sporozoite and merozoíto of Plasmodium

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    Lilian M. Spencer

    2016-05-01

    Full Text Available Malaria or paludismo is caused in humans by four species of Plasmodium belonging to phylum Apicomplexa: ovale, malaria, vivax and falciparum, being the last, the responsible of the clinical complication and death in the vertebrate host. Plasmodium parasite possess a specialized secretory organelles called rhoptries, micronemes and dense granules that facilitate invasion of host cells. The sporozoite stage of Plasmodium travels through the different cells of vertebrate host until it reaches the hepatocyte and have been form the parasitophorous vacuole. The infected hepatocytes rupture, results in the releasing thousands of daughter merozoites that invade the erythrocytes with the formation of parasitophorous vacuole too. Several researchers suggest the gliding motility mechanism as the responsible of hepatocyte invasion. While, which the erythrocyte invasion process has been described as the result of tree steps: first contact, re-orientation and invasion. In this review the surface proteins of merozoites and esporozoites are pointed out as the most important factors for the molecular invasion mechanisms until the elaboration of the parasitophorous vacuole. These proteins that take part in these mechanisms are the possible candidates in the design of an anti-malaria vaccine.

  14. Towards a molecular understanding of the apicomplexan actin motor: on a road to novel targets for malaria remedies?

    Energy Technology Data Exchange (ETDEWEB)

    Kumpula, Esa-Pekka [University of Oulu, PO Box 3000, 90014 Oulu (Finland); Helmholtz Centre for Infection Research, Notkestrasse 85, 22607 Hamburg (Germany); German Electron Synchrotron, Notkestrasse 85, 22607 Hamburg (Germany); Kursula, Inari, E-mail: inari.kursula@helmholtz-hzi.de [University of Oulu, PO Box 3000, 90014 Oulu (Finland); Helmholtz Centre for Infection Research, Notkestrasse 85, 22607 Hamburg (Germany); German Electron Synchrotron, Notkestrasse 85, 22607 Hamburg (Germany); University of Bergen, Jonas Lies vei 91, 5009 Bergen (Norway)

    2015-04-16

    In this review, current structural understanding of the apicomplexan glideosome and actin regulation is described. Apicomplexan parasites are the causative agents of notorious human and animal diseases that give rise to considerable human suffering and economic losses worldwide. The most prominent parasites of this phylum are the malaria-causing Plasmodium species, which are widespread in tropical and subtropical regions, and Toxoplasma gondii, which infects one third of the world’s population. These parasites share a common form of gliding motility which relies on an actin–myosin motor. The components of this motor and the actin-regulatory proteins in Apicomplexa have unique features compared with all other eukaryotes. This, together with the crucial roles of these proteins, makes them attractive targets for structure-based drug design. In recent years, several structures of glideosome components, in particular of actins and actin regulators from apicomplexan parasites, have been determined, which will hopefully soon allow the creation of a complete molecular picture of the parasite actin–myosin motor and its regulatory machinery. Here, current knowledge of the function of this motor is reviewed from a structural perspective.

  15. Species formation by host shifting in avian malaria parasites.

    Science.gov (United States)

    Ricklefs, Robert E; Outlaw, Diana C; Svensson-Coelho, Maria; Medeiros, Matthew C I; Ellis, Vincenzo A; Latta, Steven

    2014-10-14

    The malaria parasites (Apicomplexa: Haemosporida) of birds are believed to have diversified across the avian host phylogeny well after the origin of most major host lineages. Although many symbionts with direct transmission codiversify with their hosts, mechanisms of species formation in vector-borne parasites, including the role of host shifting, are poorly understood. Here, we examine the hosts of sister lineages in a phylogeny of 181 putative species of malaria parasites of New World terrestrial birds to determine the role of shifts between host taxa in the formation of new parasite species. We find that host shifting, often across host genera and families, is the rule. Sympatric speciation by host shifting would require local reproductive isolation as a prerequisite to divergent selection, but this mechanism is not supported by the generalized host-biting behavior of most vectors of avian malaria parasites. Instead, the geographic distribution of individual parasite lineages in diverse hosts suggests that species formation is predominantly allopatric and involves host expansion followed by local host-pathogen coevolution and secondary sympatry, resulting in local shifting of parasite lineages across hosts.

  16. Complex polymorphisms in the Plasmodium falciparum multidrug resistance protein 2 gene and its contribution to antimalarial response.

    Science.gov (United States)

    Veiga, Maria Isabel; Osório, Nuno S; Ferreira, Pedro Eduardo; Franzén, Oscar; Dahlstrom, Sabina; Lum, J Koji; Nosten, Francois; Gil, José Pedro

    2014-12-01

    Plasmodium falciparum has the capacity to escape the actions of essentially all antimalarial drugs. ATP-binding cassette (ABC) transporter proteins are known to cause multidrug resistance in a large range of organisms, including the Apicomplexa parasites. P. falciparum genome analysis has revealed two genes coding for the multidrug resistance protein (MRP) type of ABC transporters: Pfmrp1, previously associated with decreased parasite drug susceptibility, and the poorly studied Pfmrp2. The role of Pfmrp2 polymorphisms in modulating sensitivity to antimalarial drugs has not been established. We herein report a comprehensive account of the Pfmrp2 genetic variability in 46 isolates from Thailand. A notably high frequency of 2.8 single nucleotide polymorphisms (SNPs)/kb was identified for this gene, including some novel SNPs. Additionally, we found that Pfmrp2 harbors a significant number of microindels, some previously not reported. We also investigated the potential association of the identified Pfmrp2 polymorphisms with altered in vitro susceptibility to several antimalarials used in artemisinin-based combination therapy and with parasite clearance time. Association analysis suggested Pfmrp2 polymorphisms modulate the parasite's in vitro response to quinoline antimalarials, including chloroquine, piperaquine, and mefloquine, and association with in vivo parasite clearance. In conclusion, our study reveals that the Pfmrp2 gene is the most diverse ABC transporter known in P. falciparum with a potential role in antimalarial drug resistance.

  17. Screening of potential targets in Plasmodium falciparum using stage-specific metabolic network analysis.

    Science.gov (United States)

    Dholakia, Neel; Dhandhukia, Pinakin; Roy, Nilanjan

    2015-11-01

    The Apicomplexa parasite Plasmodium is a major cause of death in developing countries which are less equipped to bring new medicines to the market. Currently available drugs used for treatment of malaria are limited either by inadequate efficacy, toxicity and/or increased resistance. Availability of the genome sequence, microarray data and metabolic profile of Plasmodium parasite offers an opportunity for the identification of stage-specific genes important to the organism's lifecycle. In this study, microarray data were analysed for differential expression and overlapped onto metabolic pathways to identify differentially regulated pathways essential for transition to successive erythrocytic stages. The results obtained indicate that S-adenosylmethionine decarboxylase/ornithine decarboxylase, a bifunctional enzyme required for polyamine synthesis, is important for the Plasmodium cell growth in the absence of exogenous polyamines. S-adenosylmethionine decarboxylase/ornithine decarboxylase is a valuable target for designing therapeutically useful inhibitors. One such inhibitor, [Formula: see text]-difluoromethyl ornithine, is currently in use for the treatment of African sleeping sickness caused by Trypanosoma brucei. Structural studies of ornithine decarboxylase along with known inhibitors and their analogues were carried out to screen drug databases for more effective and less toxic compounds.

  18. Neospora caninum in bovine fetuses of Minas Gerais, Brazil: genetic characteristics of rDNA Neospora caninum em fetos bovinos de Minas Gerais, Brasil: características genéticas do rDNA

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    Domingos Sávio dos Santos

    2011-12-01

    Full Text Available Neosporosis is an important cause of abortion in cattle and information on their genetics and host parasite relationships are desirable. Neospora caninum samples obtained from 24 bovine fetuses from Minas Gerais, were genetically analyzed in part of the rDNA region, coding for rRNAs. Previously, brain, heart, liver, skeletal muscle, lung, kidney, spleen, thymus, lymph nodes, ovary or testis, uterus and skin of the ear were analyzed by conventional histopathology and immunohistochemistry. Of these, eight had lesions compatible in the brain and heart and two also in skeletal muscle and liver. Three brains showed antigen identification in immunohistochemistry. Brain and heart tissues were subjected to DNA extraction for PCR, whose product of 588 bp of ITS-1 region was sequenced in three samples. We obtained 96% similarity with dozens of sequences N. caninum deposited in GenBank. The phylogenetic tree showed great conservation among isolates of N. caninum in this study and those deposited in GenBank, while well-defined and specific branches were generated against other Apicomplexa. PCR for this region is useful as a diagnosis, with good analytical specificity, but the ITS-1 region is not suitable for genetic differentiation intra species because the sequences obtained were identical to the others analyzed.A neosporose é uma importante causa de abortos em bovinos, e informações sobre sua genética e relação parasito-hospedeiro são desejáveis. Amostras de Neospora caninum, obtidas de 24 conceptos bovinos oriundos de Minas Gerais, foram analisadas geneticamente em parte da região rDNA, codificadora de rRNAs. Previamente, cérebro, coração, fígado, músculo esquelético, pulmão, rim, baço, timo, linfonodos, ovário ou testículo, útero e pele da orelha foram analisados por histopatologia convencional e imuno-histoquímica. Dessas, oito apresentaram lesões compatíveis no encéfalo e coração e dois também no músculo esquelético e f

  19. Structural and functional insights into the malaria parasite moving junction complex.

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    Brigitte Vulliez-Le Normand

    Full Text Available Members of the phylum Apicomplexa, which include the malaria parasite Plasmodium, share many features in their invasion mechanism in spite of their diverse host cell specificities and life cycle characteristics. The formation of a moving junction (MJ between the membranes of the invading apicomplexan parasite and the host cell is common to these intracellular pathogens. The MJ contains two key parasite components: the surface protein Apical Membrane Antigen 1 (AMA1 and its receptor, the Rhoptry Neck Protein (RON complex, which is targeted to the host cell membrane during invasion. In particular, RON2, a transmembrane component of the RON complex, interacts directly with AMA1. Here, we report the crystal structure of AMA1 from Plasmodium falciparum in complex with a peptide derived from the extracellular region of PfRON2, highlighting clear specificities of the P. falciparum RON2-AMA1 interaction. The receptor-binding site of PfAMA1 comprises the hydrophobic groove and a region that becomes exposed by displacement of the flexible Domain II loop. Mutations of key contact residues of PfRON2 and PfAMA1 abrogate binding between the recombinant proteins. Although PfRON2 contacts some polymorphic residues, binding studies with PfAMA1 from different strains show that these have little effect on affinity. Moreover, we demonstrate that the PfRON2 peptide inhibits erythrocyte invasion by P. falciparum merozoites and that this strong inhibitory potency is not affected by AMA1 polymorphisms. In parallel, we have determined the crystal structure of PfAMA1 in complex with the invasion-inhibitory peptide R1 derived by phage display, revealing an unexpected structural mimicry of the PfRON2 peptide. These results identify the key residues governing the interactions between AMA1 and RON2 in P. falciparum and suggest novel approaches to antimalarial therapeutics.

  20. Transcript and protein expression profile of PF11_0394, a Plasmodium falciparum protein expressed in salivary gland sporozoites

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    Schlarman Maggie S

    2012-03-01

    Full Text Available Abstract Background Plasmodium falciparum malaria is a significant problem around the world today, thus there is still a need for new control methods to be developed. Because the sporozoite displays dual infectivity for both the mosquito salivary glands and vertebrate host tissue, it is a good target for vaccine development. Methods The P. falciparum gene, PF11_0394, was chosen as a candidate for study due to its potential role in the invasion of host tissues. This gene, which was selected using a data mining approach from PlasmoDB, is expressed both at the transcriptional and protein levels in sporozoites and likely encodes a putative surface protein. Using reverse transcription-polymerase chain reaction (RT-PCR and green fluorescent protein (GFP-trafficking studies, a transcript and protein expression profile of PF11_0394 was determined. Results The PF11_0394 protein has orthologs in other Plasmodium species and Apicomplexans, but none outside of the group Apicomplexa. PF11_0394 transcript was found to be present during both the sporozoite and erythrocytic stages of the parasite life cycle, but no transcript was detected during axenic exoerythrocytic stages. Despite the presence of transcript throughout several life cycle stages, the PF11_0394 protein was only detected in salivary gland sporozoites. Conclusions PF11_0394 appears to be a protein uniquely detected in salivary gland sporozoites. Even though a specific function of PF11_0394 has not been determined in P. falciparum biology, it could be another candidate for a new vaccine.

  1. Phylogenetic Analysis of Nucleus-Encoded Acetyl-CoA Carboxylases Targeted at the Cytosol and Plastid of Algae.

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    Roger Huerlimann

    Full Text Available The understanding of algal phylogeny is being impeded by an unknown number of events of horizontal gene transfer (HGT, and primary and secondary/tertiary endosymbiosis. Through these events, previously heterotrophic eukaryotes developed photosynthesis and acquired new biochemical pathways. Acetyl-CoA carboxylase (ACCase is a key enzyme in the fatty acid synthesis and elongation pathways in algae, where ACCase exists in two locations (cytosol and plastid and in two forms (homomeric and heteromeric. All algae contain nucleus-encoded homomeric ACCase in the cytosol, independent of the origin of the plastid. Nucleus-encoded homomeric ACCase is also found in plastids of algae that arose from a secondary/tertiary endosymbiotic event. In contrast, plastids of algae that arose from a primary endosymbiotic event contain heteromeric ACCase, which consists of three nucleus-encoded and one plastid-encoded subunits. These properties of ACCase provide the potential to inform on the phylogenetic relationships of hosts and their plastids, allowing different hypothesis of endosymbiotic events to be tested. Alveolata (Dinoflagellata and Apicomplexa and Chromista (Stramenopiles, Haptophyta and Cryptophyta have traditionally been grouped together as Chromalveolata, forming the red lineage. However, recent genetic evidence groups the Stramenopiles, Alveolata and green plastid containing Rhizaria as SAR, excluding Haptophyta and Cryptophyta. Sequences coding for plastid and cytosol targeted homomeric ACCases were isolated from Isochrysis aff. galbana (TISO, Chromera velia and Nannochloropsis oculata, representing three taxonomic groups for which sequences were lacking. Phylogenetic analyses show that cytosolic ACCase strongly supports the SAR grouping. Conversely, plastidial ACCase groups the SAR with the Haptophyta, Cryptophyta and Prasinophyceae (Chlorophyta. These two ACCase based, phylogenetic relationships suggest that the plastidial homomeric ACCase was

  2. Drug-induced expansion and differentiation of V gamma 9V delta 2 T cells in vivo: the role of exogenous IL-2.

    Science.gov (United States)

    Casetti, Rita; Perretta, Gemma; Taglioni, Alessandra; Mattei, Maurizio; Colizzi, Vittorio; Dieli, Francesco; D'Offizi, Gianpiero; Malkovsky, Miroslav; Poccia, Fabrizio

    2005-08-01

    Human Vgamma9Vdelta2 T cells recognize nonpeptidic Ags generated by the 1-deoxy-d-xylulose 5-phosphate (many eubacteria, algae, plants, and Apicomplexa) and mevalonate (eukaryotes, archaebacteria, and certain eubacteria) pathways of isoprenoid synthesis. The potent Vgamma9Vdelta2 T cell reactivity 1) against certain cancer cells or 2) induced by infectious agents indicates that therapeutic augmentations of Vgamma9Vdelta2 T cell activities may be clinically beneficial. The functional characteristics of Vgamma9Vdelta2 T cells from Macaca fascicularis (cynomolgus monkey) are very similar to those from Homo sapiens. We have found that the i.v. administration of nitrogen-containing bisphosphonate or pyrophosphomonoester drugs into cynomolgus monkeys combined with s.c. low-dose (6 x 10(5) U/animal) IL-2 induces a large pool of CD27+ and CD27- effector/memory T cells in the peripheral blood of treated animals. The administration of these drugs in the absence of IL-2 is substantially less effective, indicating the importance of additional exogenous costimuli. Shortly after the costimulatory IL-2 treatment, only gammadelta (but not alphabeta) T cells expressed the CD69 activation marker, indicating that Vgamma9Vdelta2 T lymphocytes are more responsive to low-dose IL-2 than alphabeta T cells. Up to 100-fold increases in the numbers of peripheral blood Vgamma9Vdelta2 T cells were observed in animals receiving the gammadelta stimulatory drug plus IL-2. Moreover, the expanded Vgamma9Vdelta2 T cells were potent Th1 effectors capable of releasing large amounts of IFN-gamma. These results may be relevant for designing novel (or modifying current) immunotherapeutic trials with nitrogen-containing bisphosphonate or pyrophosphomonoester drugs.

  3. Comparative genome analysis reveals a conserved family of actin-like proteins in apicomplexan parasites

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    Sibley L David

    2005-12-01

    Full Text Available Abstract Background The phylum Apicomplexa is an early-branching eukaryotic lineage that contains a number of important human and animal pathogens. Their complex life cycles and unique cytoskeletal features distinguish them from other model eukaryotes. Apicomplexans rely on actin-based motility for cell invasion, yet the regulation of this system remains largely unknown. Consequently, we focused our efforts on identifying actin-related proteins in the recently completed genomes of Toxoplasma gondii, Plasmodium spp., Cryptosporidium spp., and Theileria spp. Results Comparative genomic and phylogenetic studies of apicomplexan genomes reveals that most contain only a single conventional actin and yet they each have 8–10 additional actin-related proteins. Among these are a highly conserved Arp1 protein (likely part of a conserved dynactin complex, and Arp4 and Arp6 homologues (subunits of the chromatin-remodeling machinery. In contrast, apicomplexans lack canonical Arp2 or Arp3 proteins, suggesting they lost the Arp2/3 actin polymerization complex on their evolutionary path towards intracellular parasitism. Seven of these actin-like proteins (ALPs are novel to apicomplexans. They show no phylogenetic associations to the known Arp groups and likely serve functions specific to this important group of intracellular parasites. Conclusion The large diversity of actin-like proteins in apicomplexans suggests that the actin protein family has diverged to fulfill various roles in the unique biology of intracellular parasites. Conserved Arps likely participate in vesicular transport and gene expression, while apicomplexan-specific ALPs may control unique biological traits such as actin-based gliding motility.

  4. Discovery of a Splicing Regulator Required for Cell Cycle Progression

    Energy Technology Data Exchange (ETDEWEB)

    Suvorova, Elena S.; Croken, Matthew; Kratzer, Stella; Ting, Li-Min; Conde de Felipe, Magnolia; Balu, Bharath; Markillie, Lye Meng; Weiss, Louis M.; Kim, Kami; White, Michael W.

    2013-02-01

    In the G1 phase of the cell division cycle, eukaryotic cells prepare many of the resources necessary for a new round of growth including renewal of the transcriptional and protein synthetic capacities and building the machinery for chromosome replication. The function of G1 has an early evolutionary origin and is preserved in single and multicellular organisms, although the regulatory mechanisms conducting G1 specific functions are only understood in a few model eukaryotes. Here we describe a new G1 mutant from an ancient family of apicomplexan protozoans. Toxoplasma gondii temperature-sensitive mutant 12-109C6 conditionally arrests in the G1 phase due to a single point mutation in a novel protein containing a single RNA-recognition-motif (TgRRM1). The resulting tyrosine to asparagine amino acid change in TgRRM1 causes severe temperature instability that generates an effective null phenotype for this protein when the mutant is shifted to the restrictive temperature. Orthologs of TgRRM1 are widely conserved in diverse eukaryote lineages, and the human counterpart (RBM42) can functionally replace the missing Toxoplasma factor. Transcriptome studies demonstrate that gene expression is downregulated in the mutant at the restrictive temperature due to a severe defect in splicing that affects both cell cycle and constitutively expressed mRNAs. The interaction of TgRRM1 with factors of the tri-SNP complex (U4/U6 & U5 snRNPs) indicate this factor may be required to assemble an active spliceosome. Thus, the TgRRM1 family of proteins is an unrecognized and evolutionarily conserved class of splicing regulators. This study demonstrates investigations into diverse unicellular eukaryotes, like the Apicomplexa, have the potential to yield new insights into important mechanisms conserved across modern eukaryotic kingdoms.

  5. Phylogenetic Analysis of Nucleus-Encoded Acetyl-CoA Carboxylases Targeted at the Cytosol and Plastid of Algae.

    KAUST Repository

    Huerlimann, Roger

    2015-07-01

    The understanding of algal phylogeny is being impeded by an unknown number of events of horizontal gene transfer (HGT), and primary and secondary/tertiary endosymbiosis. Through these events, previously heterotrophic eukaryotes developed photosynthesis and acquired new biochemical pathways. Acetyl-CoA carboxylase (ACCase) is a key enzyme in the fatty acid synthesis and elongation pathways in algae, where ACCase exists in two locations (cytosol and plastid) and in two forms (homomeric and heteromeric). All algae contain nucleus-encoded homomeric ACCase in the cytosol, independent of the origin of the plastid. Nucleus-encoded homomeric ACCase is also found in plastids of algae that arose from a secondary/tertiary endosymbiotic event. In contrast, plastids of algae that arose from a primary endosymbiotic event contain heteromeric ACCase, which consists of three nucleus-encoded and one plastid-encoded subunits. These properties of ACCase provide the potential to inform on the phylogenetic relationships of hosts and their plastids, allowing different hypothesis of endosymbiotic events to be tested. Alveolata (Dinoflagellata and Apicomplexa) and Chromista (Stramenopiles, Haptophyta and Cryptophyta) have traditionally been grouped together as Chromalveolata, forming the red lineage. However, recent genetic evidence groups the Stramenopiles, Alveolata and green plastid containing Rhizaria as SAR, excluding Haptophyta and Cryptophyta. Sequences coding for plastid and cytosol targeted homomeric ACCases were isolated from Isochrysis aff. galbana (TISO), Chromera velia and Nannochloropsis oculata, representing three taxonomic groups for which sequences were lacking. Phylogenetic analyses show that cytosolic ACCase strongly supports the SAR grouping. Conversely, plastidial ACCase groups the SAR with the Haptophyta, Cryptophyta and Prasinophyceae (Chlorophyta). These two ACCase based, phylogenetic relationships suggest that the plastidial homomeric ACCase was acquired by the

  6. Transcriptional Profiling of Chromera velia Under Diverse Environmental Conditions

    KAUST Repository

    Tayyrov, Annageldi

    2014-05-01

    Since its description in 2008, Chromera velia has drawn profound interest as the closest free-­‐living photosynthetic relative of apicomplexan parasites that are significant pathogens, causing enormous health and economic problems. There-­‐ fore, this newly described species holds a great potential to understand evolu-­‐ tionary basis of how photosynthetic algae evolved into the fully pathogenic Apicomplexa and how their common ancestors may have lived before they evolved into obligate parasites. Hence, the aim of this work is to understand how C. velia function and respond to different environmental conditions. This study aims to reveal how C. velia is able to respond to environmental perturbations that are applied individually and simultaneously since, studying stress factors in separation fails to elucidate complex responses to multi stress factors and un-­‐ derstanding the systemic regulation of involved genes. To extract biologically significant information and to identify genes involved in various physiological processes under variety of environmental conditions (i.e. a combination of vary-­‐ ing temperatures, iron availability, and salinity in the growth medium) we pre-­‐ pared strand specific RNA-­‐seq libraries for 83 samples in diverse environmental conditions. Here, we report the set of significantly differentially expressed genes as a re-­‐ sponse to the each condition and their combinations. Several interesting up-­‐ regulated and down-­‐regulated genes were found and their functions and in-­‐ volved pathways were studied. We showed that the profound regulation of HSP20 proteins is significant under stress conditions and hypothesized that the-­‐ se proteins might be involved in their movements.

  7. INFECCIÓN POR PROTOZOARIOS EN INDIVIDUOS DE TITÍ BEBE LECHE -S. fuscicollis-, TITÍ CABEZA BLANCA -S. oedipus-, TITÍ ARDILLA -S. sciureus-, SURICATO -S. suricatta- Y WALLABIE DE BENNETT -M. rufogriseus-: DESCRIPCIÓN DE CASOS

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    G. L. K. López

    2014-01-01

    Full Text Available La toxoplasmosis es una de las zoonosis parasitarias más comunes y de especial atención en medicina humana y veterinaria en todo el mundo. Toxoplasma gondii comparte mu - chos de sus parámetros biológicos con otros parásitos apicomplexa, pero es único por su extremadamente amplio rango de huéspedes y su especificidad tisular. La susceptibilidad en especies de primates del Nuevo Mundo y diprotodontos a la infección por protozoarios es alta. Bajo condiciones de cautiverio la toxoplasmosis es una de las infecciones más comunes en macrópodos australianos. En el presente trabajo se exponen los hallazgos clínicos y postmortem de 11 individuos de primates ( Saguinus oedipus, S. fuscicollis, Saimiri sciureus , carnívoros ( Suricata suricatta y diprotodontos ( Macropus rufogriseus , de la Fundación Zoológica de Cali, diagnosticados con toxoplasmosis mediante métodos paraclínicos e histopatológicos. En la mayoría de los casos el cuadro clínico se caracterizó principalmente por disnea, secreción nasal espumosa y signos neurológicos. Los hallazgos más importantes de la necropsia fueron lesiones en pulmón, hígado y encéfalo. Los casos aquí descritos corresponden a cuadros clínicos de ocurrencia natural y permiten entender el desarrollo fisiopatológico y la presentación clínica de las infecciones por protozoarios en especies de fauna silvestre, a pesar de la falta de un diagnóstico definitivo mediante técnicas específicas de inmunohistoquímica para las distintas etiologías.

  8. A survey of innovation through duplication in the reduced genomes of twelve parasites.

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    Jeremy D DeBarry

    Full Text Available We characterize the prevalence, distribution, divergence, and putative functions of detectable two-copy paralogs and segmental duplications in the Apicomplexa, a phylum of parasitic protists. Apicomplexans are mostly obligate intracellular parasites responsible for human and animal diseases (e.g. malaria and toxoplasmosis. Gene loss is a major force in the phylum. Genomes are small and protein-encoding gene repertoires are reduced. Despite this genomic streamlining, duplications and gene family amplifications are present. The potential for innovation introduced by duplications is of particular interest. We compared genomes of twelve apicomplexans across four lineages and used orthology and genome cartography to map distributions of duplications against genome architectures. Segmental duplications appear limited to five species. Where present, they correspond to regions enriched for multi-copy and species-specific genes, pointing toward roles in adaptation and innovation. We found a phylum-wide association of duplications with dynamic chromosome regions and syntenic breakpoints. Trends in the distribution of duplicated genes indicate that recent, species-specific duplicates are often tandem while most others have been dispersed by genome rearrangements. These trends show a relationship between genome architecture and gene duplication. Functional analysis reveals: proteases, which are vital to a parasitic lifecycle, to be prominent in putative recent duplications; a pair of paralogous genes in Toxoplasma gondii previously shown to produce the rate-limiting step in dopamine synthesis in mammalian cells, a possible link to the modification of host behavior; and phylum-wide differences in expression and subcellular localization, indicative of modes of divergence. We have uncovered trends in multiple modes of duplicate divergence including sequence, intron content, expression, subcellular localization, and functions of putative recent duplicates that

  9. Vertical Transmission of Babesia microti in BALB/c Mice: Preliminary Report.

    Science.gov (United States)

    Bednarska, Malgorzata; Bajer, Anna; Drozdowska, Anna; Mierzejewska, Ewa J; Tolkacz, Katarzyna; Welc-Falęciak, Renata

    2015-01-01

    Babesia spp. (Apicomplexa, Piroplasmida) are obligate parasites of many species of mammals, causing a malaria-like infection- babesiosis. Three routes of Babesia infection have been recognized to date. The main route is by a tick bite, the second is via blood transfusion. The third, vertical route of infection is poorly recognized and understood. Our study focused on vertical transmission of B. microti in a well-established mouse model. We assessed the success of this route of infection in BALB/c mice with acute and chronic infections of B. microti. In experimental groups, females were mated on the 1st day of Babesia infection (Group G0); on the 28th day post infection (dpi) in the post- acute phase of the parasite infection (G28); and on the 90th and 150th dpi (G90 and G150 group, respectively), in the chronic phase of the parasite infection. Pups were obtained from 58% of females mated in the post-acute phase (G28) and from 33% of females in groups G90 and G150. Mice mated in the pre-acute phase of infection (G0) did not deliver pups. Congenital B. microti infections were detected by PCR amplification of Babesia 18S rDNA in almost all pups (96%) from the experimental groups G28, G90 and G150. Parasitaemia in the F1 generation was low and varied between 0.01-0.001%. Vertical transmission of B. microti was demonstrated for the first time in BALB/c mice.

  10. Vertical Transmission of Babesia microti in BALB/c Mice: Preliminary Report.

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    Malgorzata Bednarska

    Full Text Available Babesia spp. (Apicomplexa, Piroplasmida are obligate parasites of many species of mammals, causing a malaria-like infection- babesiosis. Three routes of Babesia infection have been recognized to date. The main route is by a tick bite, the second is via blood transfusion. The third, vertical route of infection is poorly recognized and understood. Our study focused on vertical transmission of B. microti in a well-established mouse model. We assessed the success of this route of infection in BALB/c mice with acute and chronic infections of B. microti. In experimental groups, females were mated on the 1st day of Babesia infection (Group G0; on the 28th day post infection (dpi in the post- acute phase of the parasite infection (G28; and on the 90th and 150th dpi (G90 and G150 group, respectively, in the chronic phase of the parasite infection. Pups were obtained from 58% of females mated in the post-acute phase (G28 and from 33% of females in groups G90 and G150. Mice mated in the pre-acute phase of infection (G0 did not deliver pups. Congenital B. microti infections were detected by PCR amplification of Babesia 18S rDNA in almost all pups (96% from the experimental groups G28, G90 and G150. Parasitaemia in the F1 generation was low and varied between 0.01-0.001%. Vertical transmission of B. microti was demonstrated for the first time in BALB/c mice.

  11. Export of a Toxoplasma gondii rhoptry neck protein complex at the host cell membrane to form the moving junction during invasion.

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    Sébastien Besteiro

    2009-02-01

    Full Text Available One of the most conserved features of the invasion process in Apicomplexa parasites is the formation of a moving junction (MJ between the apex of the parasite and the host cell membrane that moves along the parasite and serves as support to propel it inside the host cell. The MJ was, up to a recent period, completely unknown at the molecular level. Recently, proteins originated from two distinct post-Golgi specialised secretory organelles, the micronemes (for AMA1 and the neck of the rhoptries (for RON2/RON4/RON5 proteins, have been shown to form a complex. AMA1 and RON4 in particular, have been localised to the MJ during invasion. Using biochemical approaches, we have identified RON8 as an additional member of the complex. We also demonstrated that all RON proteins are present at the MJ during invasion. Using metabolic labelling and immunoprecipitation, we showed that RON2 and AMA1 were able to interact in the absence of the other members. We also discovered that all MJ proteins are subjected to proteolytic maturation during trafficking to their respective organelles and that they could associate as non-mature forms in vitro. Finally, whereas AMA1 has previously been shown to be inserted into the parasite membrane upon secretion, we demonstrated, using differential permeabilization and loading of RON-specific antibodies into the host cell, that the RON complex is targeted to the host cell membrane, where RON4/5/8 remain associated with the cytoplasmic face. Globally, these results point toward a model of MJ organization where the parasite would be secreting and inserting interacting components on either side of the MJ, both at the host and at its own plasma membranes.

  12. A survey of hemoparasite infections in free-ranging mammals and reptiles in French Guiana.

    Science.gov (United States)

    de Thoisy, B; Michel, J C; Vogel, I; Vié, J C

    2000-10-01

    Blood smears of 1,353 free-ranging mammals (35 species) and 112 reptiles (31 species) from French Guiana were examined for hemoparasites. Parasites from 3 major groups were recorded: Apicomplexa (including hemogregarines, piroplasms, and Plasmodium spp.), Trypanosomatidae, and Filaroidea. Fifty percent of the individuals (86% of the species) were infected by parasites from at least 1 group. Hemogregarines, identified as Hepatozoon sp., infected numerous snakes with high prevalences (30-100%); infection is reported for the first time in 5 host genera of snakes: Clelia, Oxybelis, Pseustes, Rhinobotryum, and Bothriopsis. Infections were also observed in 4 marsupial species and 1 rodent. Hepatozoon spp. recorded in Didelphis albiventris (Marsupialia) and Coendou prehensilis (Rodentia) may be new species. Plasmodium sp. were observed in 2 snake species, Dipsas indica (Colubridae) and Bothrops atrox (Viperidae). Plasmodium brasilianum was recorded in all 5 primate species examined. Piroplasms were observed in all mammal orders except primates. Large terrestrial rodents were the main hosts of members of the Babesidae; 42% of Myoprocta acouchy, 36% of Dasyprocta agouti, and 44% of Agouti paca were infected. Trypanosomes were common in mammals and were recorded in 70% of the examined genera. Trypanosoma cruzi-like infections were reported in 21 mammal species, including sloths, rodents, carnivores, and primates. Microfilariae were also widespread, with higher prevalences in sloths, anteaters, and porcupines (>40% of the individuals infected) and in tamarins (95% infected). This survey highlights some potential anthropozoonotic risks due to the recent further evidence of Plasmodium brasilianum and P. malariae as a single species and to the increased diversity of hosts for Trypanosoma cruzi.

  13. Identification of MMV Malaria Box inhibitors of Perkinsus marinus using an ATP-based bioluminescence assay.

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    Yesmalie Alemán Resto

    Full Text Available "Dermo" disease caused by the protozoan parasite Perkinsus marinus (Perkinsozoa is one of the main obstacles to the restoration of oyster populations in the USA. Perkinsus spp. are also a concern worldwide because there are limited approaches to intervention against the disease. Based on the phylogenetic affinity between the Perkinsozoa and Apicomplexa, we exposed Perkinsus trophozoites to the Medicines for Malaria Venture Malaria Box, an open access compound library comprised of 200 drug-like and 200 probe-like compounds that are highly active against the erythrocyte stage of Plasmodium falciparum. Using a final concentration of 20 µM, we found that 4 days after exposure 46% of the compounds were active against P. marinus trophozoites. Six compounds with IC50 in the µM range were used to compare the degree of susceptibility in vitro of eight P. marinus strains from the USA and five Perkinsus species from around the world. The three compounds, MMV666021, MMV665807 and MMV666102, displayed a uniform effect across Perkinsus strains and species. Both Perkinsus marinus isolates and Perkinsus spp. presented different patterns of response to the panel of compounds tested, supporting the concept of strain/species variability. Here, we expanded the range of compounds available for inhibiting Perkinsus proliferation in vitro and characterized Perkinsus phenotypes based on their resistance to six compounds. We also discuss the implications of these findings in the context of oyster management. The Perkinsus system offers the potential for investigating the mechanism of action of the compounds of interest.

  14. Neotropical Zoonotic Parasites in Bush Dogs (Speothos venaticus) from Upper Paraná Atlantic Forests in Misiones, Argentina.

    Science.gov (United States)

    Vizcaychipi, Katherina A; Rinas, Miguel; Irazu, Lucia; Miyagi, Adriana; Argüelles, Carina F; DeMatteo, Karen E

    2016-10-01

    Wildlife remains an important source of zoonotic diseases for the most vulnerable groups of humans, primarily those living in rural areas or coexisting with forest. The Upper Paraná Atlantic forest of Misiones, Argentina is facing ongoing environmental and anthropogenic changes, which affect the local biodiversity, including the bush dog (Speothos venaticus), a small canid considered Near Threatened globally and Endangered locally. This project aimed to expand the knowledge of zoonotic parasites present in the bush dog and the potential implications for human health and conservation medicine. From May to August 2011, a detection dog located 34 scats that were genetically confirmed as bush dog and georeferenced to northern Misiones. Of these 34 scats, 27 had sufficient quantity that allowed processing for zoonotic parasites using morphological (sedimentation and flotation) and antigen (coproantigen technique) analyses. Within these 27 scats, we determined that the parasitic prevalence was 63.0% (n = 17) with 8 (47.1%) having mixed infections with 2-4 parasitic genera. No significant differences (p > 0.05) between sampling areas, sex, and parasite taxa were found. We were able to summarize the predominant nematodes (Ancylostoma caninum, Toxocara canis, and Lagochilascaris spp.), cestodes (Taenia spp. and Spirometra spp.), and apicomplexa (Cystoisospora caninum) found in these bush dogs. With the copro-ELISA technique, 14.8% (n = 4) of the samples were positive for Echinococcus spp. This study represents the first comprehensive study about parasitic fauna with zoonotic potential in the free-ranging bush dog. This information combined with the innovative set of techniques used to collect the samples constitute a valuable contribution that can be used in control programs, surveillance of zoonotic diseases, and wildlife conservation, both regionally and across the bush dog's broad distribution.

  15. Cats and Toxoplasma gondii: A systematic review and meta-analysis in Iran

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    Mohammad T. Rahimi

    2015-02-01

    Full Text Available Toxoplasma gondii is a cosmopolitan zoonotic intracellular coccidian of the phylum Apicomplexa infecting warm-blooded animals and human beings. This protozoan causes a significant public health problem in humans and imposes considerable economic losses and damages to husbandry industries. The final host, cats, accounts for all of these significant burdens. Hence the present study was designed to analyse and review the overall prevalence rate of T. gondii infection in cats in Iran for the first time. In the present study data collection (published and unpublished papers, abstracts of proceedings of national parasitology congresses and dissertations was systematically undertaken on electronic databases including PubMed, Google Scholar, Ebsco, Science Direct, Scopus, Magiran, Irandoc, IranMedex and Scientific Information Database. A total of 21 studies from 1975 to 2013 reporting prevalence of Toxoplasma infection in cats from different areas in Iran met the eligibility criteria. The pooled proportion of toxoplasmosis using the random-effect model amongst cats was estimated at 33.6% (95% confidence interval [CI] 22.05–46.41. The prevalence rate of cat toxoplasmosis in various regions of Iran ranged from 1.2% to 89.2%. Firstly, this study establishes a crude prevalence rate of T. gondii infection in cats. Secondly, it discusses the role of significant risk factors including sex, age and being either household or stray cats, in the epidemiology of the disease. Furthermore, the current study determines gaps and drawbacks in the prior studies that are useful to keep in mind to assist in designing more accurate investigations in future.

  16. Identification of a novel and unique transcription factor in the intraerythrocytic stage of Plasmodium falciparum.

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    Kanako Komaki-Yasuda

    Full Text Available The mechanisms of stage-specific gene regulation in the malaria parasite Plasmodium falciparum are largely unclear, with only a small number of specific regulatory transcription factors (AP2 family having been identified. In particular, the transcription factors that function in the intraerythrocytic stage remain to be elucidated. Previously, as a model case for stage-specific transcription in the P. falciparum intraerythrocytic stage, we analyzed the transcriptional regulation of pf1-cys-prx, a trophozoite/schizont-specific gene, and suggested that some nuclear factors bind specifically to the cis-element of pf1-cys-prx and enhance transcription. In the present study, we purified nuclear factors from parasite nuclear extract by 5 steps of chromatography, and identified a factor termed PREBP. PREBP is not included in the AP2 family, and is a novel protein with four K-homology (KH domains. The KH domain is known to be found in RNA-binding or single-stranded DNA-binding proteins. PREBP is well conserved in Plasmodium species and partially conserved in phylum Apicomplexa. To evaluate the effects of PREBP overexpression, we used a transient overexpression and luciferase assay combined approach. Overexpression of PREBP markedly enhanced luciferase expression under the control of the pf1-cys-prx cis-element. These results provide the first evidence of a novel transcription factor that activates the gene expression in the malaria parasite intraerythrocytic stage. These findings enhance our understanding of the evolution of specific transcription machinery in Plasmodium and other eukaryotes.

  17. Molecular approaches to malaria and Babesisosis diagnosis

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    G. L. McLaughlin

    1992-01-01

    Full Text Available The development of additional methods for detecting and identifuing Babesia and Plasmodium infections may be useful in disease monitoring, management and control efforts. To preliminarily evaluate sunthetic peptide-based serodiagnosis, a hydrophilic sequence (DDESEFDKEKwas selected from published BabR gene of B. bovis. Immunization of rabbits and cattle with the hemocyanin-conjugated peptide elicited antibody responses that specifically detected both P. falciparum and B. bovis antigens by immunofluorescence and Western blots. Using a dot-ELISA with this peptide, antisera from immunized and naturally-infected cattle, and immunized rodents, were specifically detected. Reactivity was weak and correlated with peptide immunization or infection. DNA-based detection using repetitive DNA was species-specific in dot-blot formats for B. bovis DNA, and in both dot-blot and in situ formats for P. falciparum; a streamlined enzymelinked synthetic DNA assay for P. falciparum detected 30 parasites/mm(cúbicos from patient blood using either colorimetric (2-15 h color development or chemiluminescent detection (0.5-6-min. exposures. Serodiagnostic and DNA hybridization methods may be complementary in the respective detection of both chronic and acute infections. However, recent improvements in the polymerase chain reaction (PCR make feasible a more sensitive and uniform approach to the diagnosis of these and other infectious disease complexes, with appropriate primers and processing methods. An analysis of ribosomal DNA genes of Plasmodium and Toxoplasma identified Apicomplexa-conserved sequence regions. Specific and distinctive PCR profiles were obtained for primers spanning the internal transcribed spacer locus for each of several Plasmodium and Babesia species.

  18. Characterization of a nuclear pore protein sheds light on the roles and composition of the Toxoplasma gondii nuclear pore complex.

    Science.gov (United States)

    Courjol, Flavie; Mouveaux, Thomas; Lesage, Kevin; Saliou, Jean-Michel; Werkmeister, Elisabeth; Bonabaud, Maurine; Rohmer, Marine; Slomianny, Christian; Lafont, Franck; Gissot, Mathieu

    2017-01-30

    The nuclear pore is a key structure in eukaryotes regulating nuclear-cytoplasmic transport as well as a wide range of cellular processes. Here, we report the characterization of the first Toxoplasma gondii nuclear pore protein, named TgNup302, which appears to be the orthologue of the mammalian Nup98-96 protein. We produced a conditional knock-down mutant that expresses TgNup302 under the control of an inducible tetracycline-regulated promoter. Under ATc treatment, a substantial decrease of TgNup302 protein in inducible knock-down (iKD) parasites was observed, causing a delay in parasite proliferation. Moreover, the nuclear protein TgENO2 was trapped in the cytoplasm of ATc-treated mutants, suggesting that TgNup302 is involved in nuclear transport. Fluorescence in situ hybridization revealed that TgNup302 is essential for 18S RNA export from the nucleus to the cytoplasm, while global mRNA export remains unchanged. Using an affinity tag purification combined with mass spectrometry, we identified additional components of the nuclear pore complex, including proteins potentially interacting with chromatin. Furthermore, reverse immunoprecipitation confirmed their interaction with TgNup302, and structured illuminated microscopy confirmed the NPC localization of some of the TgNup302-interacting proteins. Intriguingly, facilitates chromatin transcription complex (FACT) components were identified, suggesting the existence of an NPC-chromatin interaction in T. gondii. Identification of TgNup302-interacting proteins also provides the first glimpse at the NPC structure in Apicomplexa, suggesting a structural conservation of the NPC components between distant eukaryotes.

  19. A novel tetratricopeptide repeat (TPR containing PP5 serine/threonine protein phosphatase in the malaria parasite, Plasmodium falciparum

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    Adams Brian

    2001-11-01

    Full Text Available Abstract Background The malarial parasite, Plasmodium falciparum (Pf, is responsible for nearly 2 million deaths worldwide. However, the mechanisms of cellular signaling in the parasite remain largely unknown. Recent discovery of a few protein kinases and phosphatases point to a thriving reversible phosphorylation system in the parasite, although their function and regulation need to be determined. Results We provide biochemical and sequence evidence for a protein serine/threonine phosphatase type PP5 in Plasmodium falciparum, and named it PfPP5. The 594-amino acid polypeptide was encoded by a 1785 nucleotide long intronless gene in the parasite. The recombinant protein, expressed in bacteria, was indistinguishable from native PfPP5. Sequencing comparison indicated that the extra-long N-terminus of PfPP5 outside the catalytic core contained four tetratricopeptide repeats (TPRs, compared to three such repeats in other PP5 phosphatases. The PfPP5 N-terminus was required for stimulation of the phosphatase activity by polyunsaturated fatty acids. Co-immunoprecipitation demonstrated an interaction between native PfPP5 and Pf heat shock protein 90 (hsp90. PfPP5 was expressed in all the asexual erythrocytic stages of the parasite, and was moderately sensitive to okadaic acid. Conclusions This is the first example of a TPR-domain protein in the Apicomplexa family of parasites. Since TPR domains play important roles in protein-protein interaction, especially relevant to the regulation of PP5 phosphatases, PfPP5 is destined to have a definitive role in parasitic growth and signaling pathways. This is exemplified by the interaction between PfPP5 and the cognate chaperone hsp90.

  20. Immune response in the adipose tissue of lean mice infected with the protozoan parasite Neospora caninum.

    Science.gov (United States)

    Teixeira, Luzia; Moreira, João; Melo, Joana; Bezerra, Filipa; Marques, Raquel M; Ferreirinha, Pedro; Correia, Alexandra; Monteiro, Mariana P; Ferreira, Paula G; Vilanova, Manuel

    2015-06-01

    The adipose tissue can make important contributions to immune function. Nevertheless, only a limited number of reports have investigated in lean hosts the immune response elicited in this tissue upon infection. Previous studies suggested that the intracellular protozoan Neospora caninum might affect adipose tissue physiology. Therefore, we investigated in mice challenged with this protozoan if immune cell populations within adipose tissue of different anatomical locations could be differently affected. Early in infection, parasites were detected in the adipose tissue and by 7 days of infection increased numbers of macrophages, regulatory T (Treg) cells and T-bet(+) cells were observed in gonadal, mesenteric, omental and subcutaneous adipose tissue. Increased expression of interferon-γ was also detected in gonadal adipose tissue of infected mice. Two months after infection, parasite DNA was no longer detected in these tissues, but T helper type 1 (Th1) cell numbers remained above control levels in the infected mice. Moreover, the Th1/Treg cell ratio was higher than that of controls in the mesenteric and subcutaneous adipose tissue. Interestingly, chronically infected mice presented a marked increase of serum leptin, a molecule that plays a role in energy balance regulation as well as in promoting Th1-type immune responses. Altogether, we show that an apicomplexa parasitic infection influences immune cellular composition of adipose tissue throughout the body as well as adipokine production, still noticed at a chronic phase of infection when parasites were already cleared from that particular tissue. This strengthens the emerging view that infections can have long-term consequences for the physiology of adipose tissue.

  1. Characterization and localization of a hybrid non-ribosomal peptide synthetase and polyketide synthase gene from the toxic dinoflagellate Karenia brevis.

    Science.gov (United States)

    López-Legentil, Susanna; Song, Bongkeun; DeTure, Michael; Baden, Daniel G

    2010-02-01

    The toxic dinoflagellate Karenia brevis, a causative agent of the red tides in Florida, produces a series of toxic compounds known as brevetoxins and their derivatives. Recently, several putative genes encoding polyketide synthase (PKS) were identified from K. brevis in an effort to elucidate the genetic systems involved in brevetoxin production. In this study, novel PKS sequences were isolated from three clones of K. brevis. Eighteen unique sequences were obtained for the PKS ketosynthase (KS) domain of K. brevis. Phylogenetic comparison with closely related PKS genes revealed that 16 grouped with cyanobacteria sequences, while the remaining two grouped with Apicomplexa and previously reported sequences for K. brevis. A fosmid library was also constructed to further characterize PKS genes detected in K. brevis Wilson clone. Several fosmid clones were positive for the presence of PKS genes, and one was fully sequenced to determine the full structure of the PKS cluster. A hybrid non ribosomal peptide synthetase and PKS (NRPS-PKS) gene cluster of 16,061 bp was isolated. In addition, we assessed whether the isolated gene was being actively expressed using reverse transcription polymerase chain reaction (RT-PCR) and determined its localization at the cellular level by chloroplast isolation. RT-PCR analyses revealed that this gene was actively expressed in K. brevis cultures. The hybrid NRPS-PKS gene cluster was located in the chloroplast, suggesting that K. brevis acquired the ability to produce some of its secondary metabolites through endosymbiosis with ancestral cyanobacteria. Further work is needed to determine the compound produced by the NRPS-PKS hybrid, to find other PKS gene sequences, and to assess their role in K. brevis toxin biosynthetic pathway.

  2. Comparative genomics of the apicomplexan parasites Toxoplasma gondii and neospora caninum: Coccidia differing in host range and transmission strategy

    KAUST Repository

    Reid, Adam James

    2012-03-22

    Toxoplasma gondii is a zoonotic protozoan parasite which infects nearly one third of the human population and is found in an extraordinary range of vertebrate hosts. Its epidemiology depends heavily on horizontal transmission, especially between rodents and its definitive host, the cat. Neospora caninum is a recently discovered close relative of Toxoplasma, whose definitive host is the dog. Both species are tissue-dwelling Coccidia and members of the phylum Apicomplexa; they share many common features, but Neospora neither infects humans nor shares the same wide host range as Toxoplasma, rather it shows a striking preference for highly efficient vertical transmission in cattle. These species therefore provide a remarkable opportunity to investigate mechanisms of host restriction, transmission strategies, virulence and zoonotic potential. We sequenced the genome of N. caninum and transcriptomes of the invasive stage of both species, undertaking an extensive comparative genomics and transcriptomics analysis. We estimate that these organisms diverged from their common ancestor around 28 million years ago and find that both genomes and gene expression are remarkably conserved. However, in N. caninum we identified an unexpected expansion of surface antigen gene families and the divergence of secreted virulence factors, including rhoptry kinases. Specifically we show that the rhoptry kinase ROP18 is pseudogenised in N. caninum and that, as a possible consequence, Neospora is unable to phosphorylate host immunity-related GTPases, as Toxoplasma does. This defense strategy is thought to be key to virulence in Toxoplasma. We conclude that the ecological niches occupied by these species are influenced by a relatively small number of gene products which operate at the host-parasite interface and that the dominance of vertical transmission in N. caninum may be associated with the evolution of reduced virulence in this species.

  3. Responses of soil microeukaryotic communities to short-term fumigation-incubation revealed by MiSeq amplicon sequencing

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    Lin eChen

    2015-10-01

    Full Text Available In soil microbiology, there is a ‘paradox’ of soil organic carbon (SOC mineralization, which is that even though chloroform fumigation destroys majority of the soil microbial biomass, SOC mineralization continues at the same rate as in the non-fumigated soil during the incubation period. Soil microeukaryotes as important SOC decomposers, however, their community-level responses to chloroform fumigation are not well understood. Using the 18S rRNA gene amplicon sequencing, we analyzed the composition, diversity and C-metabolic functions of a grassland soil and an arable soil microeukaryotic community in response to fumigation followed by a 30-day incubation. The grassland and arable soil microeukaryotic communities were dominated by the fungal Ascomycota (80.5–93.1% of the fungal sequences, followed by the protistan Cercozoa and Apicomplexa. In the arable soil fungal community, the predominance of the class Sordariomycetes was replaced by the class Eurotiomycetes after fumigation at days 7 and 30 of the incubation. Fumigation changed the microeukaryotic α-diversity in the grassland soil at days 0 and 7, and β-diversity in the arable soil at days 7 and 30. Network analysis indicated that after fumigation fungi were important groups closely related to other taxa. Most phylotypes (especially Sordariomycetes, Dothideomycetes, Coccidia and uncultured Chytridiomycota were inhibited, and only a few were positively stimulated by fumigation. Despite the inhibited Sordariomycetes, the fumigated communities mainly consisted of Eurotiomycetes and Sordariomycetes (21.9% and 36.5% relative frequency, respectively, which are able to produce hydrolytic enzymes associated with SOC mineralization. Our study suggests that fumigation not only decreases biomass size, but modulates the composition and diversity of the soil microeukaryotic communities, which are capable of driving SOC mineralization by release of hydrolytic enzymes during short-term fumigation-incubation.

  4. Characterisation and expression of a PP1 serine/threonine protein phosphatase (PfPP1 from the malaria parasite, Plasmodium falciparum: demonstration of its essential role using RNA interference

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    Musiyenko Alla

    2002-04-01

    Full Text Available Abstract Background Reversible protein phosphorylation is relatively unexplored in the intracellular protozoa of the Apicomplexa family that includes the genus Plasmodium, to which belong the causative agents of malaria. Members of the PP1 family represent the most highly conserved protein phosphatase sequences in phylogeny and play essential regulatory roles in various cellular pathways. Previous evidence suggested a PP1-like activity in Plasmodium falciparum, not yet identified at the molecular level. Results We have identified a PP1 catalytic subunit from P. falciparum and named it PfPP1. The predicted primary structure of the 304-amino acid long protein was highly similar to PP1 sequences of other species, and showed conservation of all the signature motifs. The purified recombinant protein exhibited potent phosphatase activity in vitro. Its sensitivity to specific phosphatase inhibitors was characteristic of the PP1 class. The authenticity of the PfPP1 cDNA was further confirmed by mutational analysis of strategic amino acid residues important in catalysis. The protein was expressed in all erythrocytic stages of the parasite. Abrogation of PP1 expression by synthetic short interfering RNA (siRNA led to inhibition of parasite DNA synthesis. Conclusions The high sequence similarity of PfPP1 with other PP1 members suggests conservation of function. Phenotypic gene knockdown studies using siRNA confirmed its essential role in the parasite. Detailed studies of PfPP1 and its regulation may unravel the role of reversible protein phosphorylation in the signalling pathways of the parasite, including glucose metabolism and parasitic cell division. The use of siRNA could be an important tool in the functional analysis of Apicomplexan genes.

  5. Basal body structure and composition in the apicomplexans Toxoplasma and Plasmodium.

    Science.gov (United States)

    Francia, Maria E; Dubremetz, Jean-Francois; Morrissette, Naomi S

    2015-01-01

    The phylum Apicomplexa encompasses numerous important human and animal disease-causing parasites, including the Plasmodium species, and Toxoplasma gondii, causative agents of malaria and toxoplasmosis, respectively. Apicomplexans proliferate by asexual replication and can also undergo sexual recombination. Most life cycle stages of the parasite lack flagella; these structures only appear on male gametes. Although male gametes (microgametes) assemble a typical 9+2 axoneme, the structure of the templating basal body is poorly defined. Moreover, the relationship between asexual stage centrioles and microgamete basal bodies remains unclear. While asexual stages of Plasmodium lack defined centriole structures, the asexual stages of Toxoplasma and closely related coccidian apicomplexans contain centrioles that consist of nine singlet microtubules and a central tubule. There are relatively few ultra-structural images of Toxoplasma microgametes, which only develop in cat intestinal epithelium. Only a subset of these include sections through the basal body: to date, none have unambiguously captured organization of the basal body structure. Moreover, it is unclear whether this basal body is derived from pre-existing asexual stage centrioles or is synthesized de novo. Basal bodies in Plasmodium microgametes are thought to be synthesized de novo, and their assembly remains ill-defined. Apicomplexan genomes harbor genes encoding δ- and ε-tubulin homologs, potentially enabling these parasites to assemble a typical triplet basal body structure. Moreover, the UNIMOD components (SAS6, SAS4/CPAP, and BLD10/CEP135) are conserved in these organisms. However, other widely conserved basal body and flagellar biogenesis elements are missing from apicomplexan genomes. These differences may indicate variations in flagellar biogenesis pathways and in basal body arrangement within the phylum. As apicomplexan basal bodies are distinct from their metazoan counterparts, it may be possible to

  6. Identification of putative cis-regulatory elements in Cryptosporidium parvum by de novo pattern finding

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    Kissinger Jessica C

    2007-01-01

    Full Text Available Abstract Background Cryptosporidium parvum is a unicellular eukaryote in the phylum Apicomplexa. It is an obligate intracellular parasite that causes diarrhea and is a significant AIDS-related pathogen. Cryptosporidium parvum is not amenable to long-term laboratory cultivation or classical molecular genetic analysis. The parasite exhibits a complex life cycle, a broad host range, and fundamental mechanisms of gene regulation remain unknown. We have used data from the recently sequenced genome of this organism to uncover clues about gene regulation in C. parvum. We have applied two pattern finding algorithms MEME and AlignACE to identify conserved, over-represented motifs in the 5' upstream regions of genes in C. parvum. To support our findings, we have established comparative real-time -PCR expression profiles for the groups of genes examined computationally. Results We find that groups of genes that share a function or belong to a common pathway share upstream motifs. Different motifs are conserved upstream of different groups of genes. Comparative real-time PCR studies show co-expression of genes within each group (in sub-sets during the life cycle of the parasite, suggesting co-regulation of these genes may be driven by the use of conserved upstream motifs. Conclusion This is one of the first attempts to characterize cis-regulatory elements in the absence of any previously characterized elements and with very limited expression data (seven genes only. Using de novo pattern finding algorithms, we have identified specific DNA motifs that are conserved upstream of genes belonging to the same metabolic pathway or gene family. We have demonstrated the co-expression of these genes (often in subsets using comparative real-time-PCR experiments thus establishing evidence for these conserved motifs as putative cis-regulatory elements. Given the lack of prior information concerning expression patterns and organization of promoters in C. parvum we

  7. The transcriptome of Toxoplasma gondii

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    Roos David S

    2005-12-01

    Full Text Available Abstract Background Toxoplasma gondii gives rise to toxoplasmosis, among the most prevalent parasitic diseases of animals and man. Transformation of the tachzyoite stage into the latent bradyzoite-cyst form underlies chronic disease and leads to a lifetime risk of recrudescence in individuals whose immune system becomes compromised. Given the importance of tissue cyst formation, there has been intensive focus on the development of methods to study bradyzoite differentiation, although the molecular basis for the developmental switch is still largely unknown. Results We have used serial analysis of gene expression (SAGE to define the Toxoplasma gondii transcriptome of the intermediate-host life cycle that leads to the formation of the bradyzoite/tissue cyst. A broad view of gene expression is provided by >4-fold coverage from nine distinct libraries (~300,000 SAGE tags representing key developmental transitions in primary parasite populations and in laboratory strains representing the three canonical genotypes. SAGE tags, and their corresponding mRNAs, were analyzed with respect to abundance, uniqueness, and antisense/sense polarity and chromosome distribution and developmental specificity. Conclusion This study demonstrates that phenotypic transitions during parasite development were marked by unique stage-specific mRNAs that accounted for 18% of the total SAGE tags and varied from 1–5% of the tags in each developmental stage. We have also found that Toxoplasma mRNA pools have a unique parasite-specific composition with 1 in 5 transcripts encoding Apicomplexa-specific genes functioning in parasite invasion and transmission. Developmentally co-regulated genes were dispersed across all Toxoplasma chromosomes, as were tags representing each abundance class, and a variety of biochemical pathways indicating that trans-acting mechanisms likely control gene expression in this parasite. We observed distinct similarities in the specificity and

  8. A complex small RNA repertoire is generated by a plant/fungal-like machinery and effected by a metazoan-like Argonaute in the single-cell human parasite Toxoplasma gondii.

    Science.gov (United States)

    Braun, Laurence; Cannella, Dominique; Ortet, Philippe; Barakat, Mohamed; Sautel, Céline F; Kieffer, Sylvie; Garin, Jérôme; Bastien, Olivier; Voinnet, Olivier; Hakimi, Mohamed-Ali

    2010-05-27

    In RNA silencing, small RNAs produced by the RNase-III Dicer guide Argonaute-like proteins as part of RNA-induced silencing complexes (RISC) to regulate gene expression transcriptionally or post-transcriptionally. Here, we have characterized the RNA silencing machinery and exhaustive small RNAome of Toxoplasma gondii, member of the Apicomplexa, a phylum of animal- and human-infecting parasites that cause extensive health and economic damages to human populations worldwide. Remarkably, the small RNA-generating machinery of Toxoplasma is phylogenetically and functionally related to that of plants and fungi, and accounts for an exceptionally diverse array of small RNAs. This array includes conspicuous populations of repeat-associated small interfering RNA (siRNA), which, as in plants, likely generate and maintain heterochromatin at DNA repeats and satellites. Toxoplasma small RNAs also include many microRNAs with clear metazoan-like features whose accumulation is sometimes extremely high and dynamic, an unexpected finding given that Toxoplasma is a unicellular protist. Both plant-like heterochromatic small RNAs and metazoan-like microRNAs bind to a single Argonaute protein, Tg-AGO. Toxoplasma miRNAs co-sediment with polyribosomes, and thus, are likely to act as translational regulators, consistent with the lack of catalytic residues in Tg-AGO. Mass spectrometric analyses of the Tg-AGO protein complex revealed a common set of virtually all known RISC components so far characterized in human and Drosophila, as well as novel proteins involved in RNA metabolism. In agreement with its loading with heterochromatic small RNAs, Tg-AGO also associates substoichiometrically with components of known chromatin-repressing complexes. Thus, a puzzling patchwork of silencing processor and effector proteins from plant, fungal and metazoan origin accounts for the production and action of an unsuspected variety of small RNAs in the single-cell parasite Toxoplasma and possibly in other

  9. Utilization of inherent miRNAs in functional analyses of Toxoplasma gondii genes.

    Science.gov (United States)

    Crater, Anna K; Manni, Emad; Ananvoranich, Sirinart

    2015-01-01

    MicroRNAs (miRNAs) are crucial genetic effectors partaking in numerous mechanisms of gene regulation in eukaryotic organisms. Recent discoveries of miRNA in Toxoplasma gondii, an intracellular obligate parasite of the phylum Apicomplexa, suggested possible roles of T. gondii miRNAs (Tg-miRNAs) in the post-transcriptional gene regulation and in the cell biology of the parasite. To gain a better understanding of the involvement of Tg-miRNAs in regulating the parasite gene expression, a dual luciferase reporter system was used in the examination and evaluation of the effects of endogenous Tg-miRNAs, their mimics and inhibitors. A Renilla luciferase (Rnluc) transcript was engineered to carry independent binding sites of two abundant species, namely Tg-miR-60a and Tg-miR-4a, so that the expression of Rnluc was silenced in a sequence specific manner by Tg-miR-60a and Tg-miR-4a. Notably, Tg-miR-60a, but not Tg-miR-4a, caused the levels of Rnluc transcripts to decrease. These findings strongly suggested that T. gondii employs the Tg-miRNA species-specific mode of silencing actions: transcript degradation by Tg-miR-60a, and translational suppression by Tg-miR-4a. Herein we developed a genetic system that exploits and directs the most abundant Tg-miR-60a for loss-of-function analyses in T. gondii. As a proof of principle, we showed that when the binding sites for Tg-miR-60a were introduced into the parasite transcripts via homologous recombination at the locus of (i) DEAD-box RNA helicase (TgHoDI), or (ii) lactate dehydrogenase isoform 1 (TgLDH1), the expression levels of the selected genes can be altered. It was thus proven that inherit Tg-miR-60a could be directed and used to assist in the loss-of-function analyses.

  10. PvRON2, a new Plasmodium vivax rhoptry neck antigen

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    Curtidor Hernando

    2011-03-01

    Full Text Available Abstract Background Rhoptries are specialized organelles from parasites belonging to the phylum Apicomplexa; they secrete their protein content during invasion of host target cells and are sorted into discrete subcompartments within rhoptry neck or bulb. This distribution is associated with these proteins' role in tight junction (TJ and parasitophorous vacuole (PV formation, respectively. Methods Plasmodium falciparum RON2 amino acid sequence was used as bait for screening the codifying gene for the homologous protein in the Plasmodium vivax genome. Gene synteny, as well as identity and similarity values, were determined for ron2 and its flanking genes among P. falciparum, P. vivax and other malarial parasite genomes available at PlasmoDB and Sanger Institute databases. Pvron2 gene transcription was determined by RT-PCR of cDNA obtained from the P. vivax VCG-1 strain. Protein expression and localization were assessed by Western blot and immunofluorescence using polyclonal anti-PvRON2 antibodies. Co-localization was confirmed using antibodies directed towards specific microneme and rhoptry neck proteins. Results and discussion The first P. vivax rhoptry neck protein (named here PvRON2 has been identified in this study. PvRON2 is a 2,204 residue-long protein encoded by a single 6,615 bp exon containing a hydrophobic signal sequence towards the amino-terminus, a transmembrane domain towards the carboxy-terminus and two coiled coil α-helical motifs; these are characteristic features of several previously described vaccine candidates against malaria. This protein also contains two tandem repeats within the interspecies variable sequence possibly involved in evading a host's immune system. PvRON2 is expressed in late schizonts and localized in rhoptry necks similar to what has been reported for PfRON2, which suggests its participation during target cell invasion. Conclusions The identification and partial characterization of the first P. vivax

  11. Consistent and contrasting properties of lineage-specific genes in the apicomplexan parasites Plasmodium and Theileria

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    Kissinger Jessica C

    2008-04-01

    Full Text Available Abstract Background Lineage-specific genes, the genes that are restricted to a limited subset of related organisms, may be important in adaptation. In parasitic organisms, lineage-specific gene products are possible targets for vaccine development or therapeutics when these genes are absent from the host genome. Results In this study, we utilized comparative approaches based on a phylogenetic framework to characterize lineage-specific genes in the parasitic protozoan phylum Apicomplexa. Genes from species in two major apicomplexan genera, Plasmodium and Theileria, were categorized into six levels of lineage specificity based on a nine-species phylogeny. In both genera, lineage-specific genes tend to have a higher level of sequence divergence among sister species. In addition, species-specific genes possess a strong codon usage bias compared to other genes in the genome. We found that a large number of genus- or species-specific genes are putative surface antigens that may be involved in host-parasite interactions. Interestingly, the two parasite lineages exhibit several notable differences. In Plasmodium, the (G + C content at the third codon position increases with lineage specificity while Theileria shows the opposite trend. Surface antigens in Plasmodium are species-specific and mainly located in sub-telomeric regions. In contrast, surface antigens in Theileria are conserved at the genus level and distributed across the entire lengths of chromosomes. Conclusion Our results provide further support for the model that gene duplication followed by rapid divergence is a major mechanism for generating lineage-specific genes. The result that many lineage-specific genes are putative surface antigens supports the hypothesis that lineage-specific genes could be important in parasite adaptation. The contrasting properties between the lineage-specific genes in two major apicomplexan genera indicate that the mechanisms of generating lineage-specific genes

  12. Babesia microti: prevalence in wild rodents and Ixodes ricinus ticks from the Mazury Lakes District of North-Eastern Poland.

    Science.gov (United States)

    Siński, Edward; Bajer, Anna; Welc, Renata; Pawełczyk, Agnieszka; Ogrzewalska, Maria; Behnke, Jerzy M

    2006-05-01

    Infections of Babesia microti (Apicomplexa, Piroplasmida), a common erythroparasitic protozoon of Holarctic rodents, are not widely acknowledged in Poland. The presence of this parasite in various species of wild rodents has been well documented throughout the northern temperate zone of North America, Europe, and Eurasia. However, human babesiosis attributable to infection with B. microti has been reported only from the north-eastern and upper midwestern United States and Japan. We recently carried out an epizootiological survey investigating the prevalence of B. microti both in the tick Ixodes ricinus and in wild rodents in North-Eastern Poland. Blood samples were collected from a total of 483 animals comprising three species: Apodemus flavicollis, Microtus arvalis, and Microtus oeconomus trapped at Urwitałt near Mikołajki in the Mazury Lakes District. Questing adult I. ricinus ticks were collected in the study sites by blanket dragging of vegetation in heterogeneous, deciduous woodland, and, in addition, rodents were carefully examined for feeding larvae and nymphs. Altogether, B. microti was detected in 9 out of 1513 I. ricinus ticks (0.6%) examined by PCR. This included 163 adults (92 females and 71 males), 50 nymphs, and 1300 larvae 3%, 8%, and 0% of which were PCR-positive, respectively. Of 85 A. flavicollis, 374 M. arvalis and 24 M. oeconomus, 1%, 12.8%, and 42% were parasitaemic, respectively, as determined by microscopic examination of blood smears stained with Giemsa. B. microti DNA, extracted from 53 M. arvalis and 5 M. oeconomus and examined by nested PCR, targeting a piroplasm-specific portion of the 18S ribosomal DNA, revealed 72% and 40%, respectively, to be PCR positive. Sequence analysis showed that all PCR-positive samples had rDNA sequences identical (100% homology) to that of the Munich B. microti strain isolated from Mus musculus. The results of this study indicate that the B. microti commonly encountered among Microtus spp. rodents is

  13. Toxoplasma gondii Cyclic AMP-Dependent Protein Kinase Subunit 3 Is Involved in the Switch from Tachyzoite to Bradyzoite Development

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    Tatsuki Sugi

    2016-05-01

    Full Text Available Toxoplasma gondii is an obligate intracellular apicomplexan parasite that infects warm-blooded vertebrates, including humans. Asexual reproduction in T. gondii allows it to switch between the rapidly replicating tachyzoite and quiescent bradyzoite life cycle stages. A transient cyclic AMP (cAMP pulse promotes bradyzoite differentiation, whereas a prolonged elevation of cAMP inhibits this process. We investigated the mechanism(s by which differential modulation of cAMP exerts a bidirectional effect on parasite differentiation. There are three protein kinase A (PKA catalytic subunits (TgPKAc1 to -3 expressed in T. gondii. Unlike TgPKAc1 and TgPKAc2, which are conserved in the phylum Apicomplexa, TgPKAc3 appears evolutionarily divergent and specific to coccidian parasites. TgPKAc1 and TgPKAc2 are distributed in the cytomembranes, whereas TgPKAc3 resides in the cytosol. TgPKAc3 was genetically ablated in a type II cyst-forming strain of T. gondii (PruΔku80Δhxgprt and in a type I strain (RHΔku80Δhxgprt, which typically does not form cysts. The Δpkac3 mutant exhibited slower growth than the parental and complemented strains, which correlated with a higher basal rate of tachyzoite-to-bradyzoite differentiation. 3-Isobutyl-1-methylxanthine (IBMX treatment, which elevates cAMP levels, maintained wild-type parasites as tachyzoites under bradyzoite induction culture conditions (pH 8.2/low CO2, whereas the Δpkac3 mutant failed to respond to the treatment. This suggests that TgPKAc3 is the factor responsible for the cAMP-dependent tachyzoite maintenance. In addition, the Δpkac3 mutant had a defect in the production of brain cysts in vivo, suggesting that a substrate of TgPKAc3 is probably involved in the persistence of this parasite in the intermediate host animals.

  14. Properties of non-coding DNA and identification of putative cis-regulatory elements in Theileria parva

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    Guo Xiang

    2008-12-01

    regulatory motifs in other species. These results suggest that these two motifs are likely to represent transcription factor binding sites in Theileria. Conclusion Theileria genomes are highly compact, with selection seemingly favoring short introns and intergenic regions. Three over-represented sequence motifs were independently identified in intergenic regions of both Theileria species, and the evidence suggests that at least two of them play a role in transcriptional control in T. parva. These are prime candidates for experimental validation of transcription factor binding sites in this single-celled eukaryotic parasite. Sequences similar to two of these Theileria motifs are conserved in Plasmodium hinting at the possibility of common regulatory machinery across the phylum Apicomplexa.

  15. ApiAP2 Factors as Candidate Regulators of Stochastic Commitment to Merozoite Production in Theileria annulata.

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    Marta Pieszko

    Apicomplexa; leading to the proposal that the mechanisms that control stage differentiation will show a degree of conservation.

  16. Effects of ionizing radiation over the structure, metabolism and infectivity of a pathogenic protozoan, Toxoplasma gondii; Efeitos da radiacao ionizante sobre a estrutura, metabolismo e infectividade de um protozoario patogenico, Toxoplasma gondii (Nicole and Manceau, 1908)

    Energy Technology Data Exchange (ETDEWEB)

    Hiramoto, Roberto Mitsuyoshi

    1998-07-01

    The intracellular parasite Toxoplasma gondii (Apicomplexa), has as definitive host domestic and wild felines and as intermediate hosts most species of mammals and birds, Including man. The infection in man is usually asymptomatic, but can become a severe and lethal illness in some special groups like the fetus of primoinfected pregnant woman, or in AIDS and transplanted patients. The transmission is due to ingestion of food or water contaminated with oocysts from cat feces as well as raw or rare cooked cyst containing meet. There is no available vaccine against toxoplasmosis, with some reports of the use ionizing radiation in order to attenuate or suppress the parasite. These studies are promising, but more research is needed to optimize the radiation process and to clarify those alterations caused on T gondii.Using a increasing doses of {sup 60} Co irradiation on T.gondii tachyzoites, we studied many parameters such as morphology, both at optical and electron microscopy level, detection of DNA fragmentation, metabolism alterations (cellular oxidative burst, protein, nucleic acids and DNA synthesis), determination of the parasite survival both in in vivo and in vitro models, antigenicity and immunogenicity after the process, cellular invasion and irradiated tachyzoite induced protection. After definition of 200 Gy of {sup 60} Co irradiation as the lower radiation dose that suppress parasite growth in vitro and in vivo, we found no detectable changes in parasite viability, its cell invasion capacity or in its structural proteins. DNA fragmentation like apoptosis or alterations of the parasite metabolism were similarly not affected by radiation. Mice infection with irradiated parasites induce partial protection when these animals were re-inoculated with non irradiated virulent parasites, inducing greater specific IgG levels as well as a longer survival. Irradiated T.gondii maintains its the ability of invasion, even under radiation effects. Based on our results we

  17. Fitting hidden Markov models of protein domains to a target species: application to Plasmodium falciparum

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    Terrapon Nicolas

    2012-05-01

    the P. falciparum proteome and the Apicomplexa phylum, and identify many domains that are not detected by previous approaches. In terms of the number of new discovered domains, the new approaches outperform the previous ones when no close species are available or when they are used to identify likely occurrences among potential domains with high E-values. All predictions on P. falciparum have been integrated into a dedicated website which pools all known/new annotations of protein domains and functions for this organism. A software implementing the two proposed approaches is available at the same address: http://www.lirmm.fr/∼terrapon/HMMfit/

  18. Bovine besnoitiosis in Switzerland: imported cases and local transmission.

    Science.gov (United States)

    Basso, Walter; Lesser, Maren; Grimm, Felix; Hilbe, Monika; Sydler, Titus; Trösch, Luzia; Ochs, Hansueli; Braun, Ueli; Deplazes, Peter

    2013-12-06

    Bovine besnoitiosis is an economically important disease of cattle, caused by Besnoitia besnoiti (Protozoa, Apicomplexa). A considerable spreading of this parasitic infection has been observed in Europe in the last ten years, mainly related to animal trade. In order to investigate the possibility of B. besnoiti being unnoticed introduced and getting established in Switzerland through the import of breeding cattle from France, a total of 767 animals (650 cattle imported from France and 117 cattle that had contact with B. besnoiti positive cattle in Swiss farms) were screened for antibodies against B. besnoiti by both a commercial ELISA and by the indirect fluorescent antibody test (IFAT). A total of 101 (13.17%) samples showed a positive reaction in ELISA (cut-off: percent of positivity [PP] ≥ 15) and 16 (2.09%) samples had IFAT titers ≥ 1:100. Eight of those samples reacted positive in Western blot (WB), corresponding to five imported Limousin cattle (two cows and one bull from France and two cows from Germany) and to three cattle born in Switzerland (one Limousin heifer born from one of the positive German cows, and two adult Braunvieh cows, that had been in contact with one of the French cows at a Swiss farm). Seven of those animals were subclinically infected and one animal showed only very mild signs. They were subsequently slaughtered, and the serological diagnosis could be confirmed by real-time PCR and/or histopathology in seven animals. The most frequent parasite localizations were the tendons and surrounding connective tissue of the distal limbs and the skin of the head region. Furthermore, B. besnoiti could be successfully isolated in vitro from one French, one German and one Swiss cattle (isolates Bb-IPZ-1-CH, Bb-IPZ-2-CH and Bb-IPZ-3-CH). In the current situation in Switzerland, prophylactic and control measures should include a serological examination of cattle to be imported from endemic areas and the culling of all confirmed positive animals from

  19. 艾美耳球虫子孢子从宿主细胞中逸出机制的初步研究%PRELIMINARY STUDY ON THE MECHANISMS OF RAPID EGRESS OF EIMERIA TENELLA SPOROZOITES FROM HOST CELLS

    Institute of Scientific and Technical Information of China (English)

    闫鑫磊; 计永胜; 田秀玲; 索静霞; 刘贤勇; 索勋

    2014-01-01

    Apicomplexan parasites infect nearly all vertebrate hosts even including humans and cause some severe diseases such as malaria, toxoplasmosis, cryptosporidiosis which are responsible for substantial economic losses. Like most intracellular pathogens, egress from host cells is a vital step of the apicomplexan parasites, which attracted attentions of many research groups.Unfortunately, as an important genus of Phylum Apicomplexa, little information of egress is known on Eimeria species which leads large amount of losses to poultry industry annually.In this report we used ethanol to induce egress of E.tenella M2e transgenic strain (EtM2e) sporozoites which express yellow fluorescent protein (YFP).Results showed that ethanol could induce egress of EtM2e sporozoites from infected Madin Derby Bovine Kidney ( MDBK) cells, and this process was depended on the mobility of the parasites.We also found that ethanol could also stimulate microneme protein discharge.Furthermore, both the course of egress and the secretion of microneme were controlled by the flux of intracellular Ca2+of the parasite.Taken together, our results preliminarily explained the mechanism of egress of eimerian parasites, which provided clues to the further study.%艾美耳球虫是一类重要的肠道病原,其裂殖生殖阶段的虫体逸出过程是造成畜禽肠道破坏的主要原因之一,但此逸出过程的机制仍鲜有报道。本研究以乙醇作为诱导剂研究柔嫩艾美耳球虫M2 e株子孢子从宿主细胞中逸出的机制。结果显示,乙醇可诱导子孢子从MDBK细胞中逸出,此逸出过程依赖于虫体的运动能力;同时,乙醇可激发子孢子逸出相关的微线体蛋白2( Mic2)的分泌释放。进一步实验证实,螯合虫体内部钙离子明显阻断了子孢子逸出及Mic2蛋白的释放。本研究初步证实了与柔嫩艾美耳球虫逸出相关的蛋白和离子,为深入解析球虫致病的分子机制、研发新型抗球

  20. Intestinal Coccidia

    Directory of Open Access Journals (Sweden)

    MJ Ggaravi

    2007-06-01

    Full Text Available Intestinal Coccidia are a subclass of Apicomplexa phylum. Eucoccidida are facultative heteroxenous, but some of them are monoxenous. They have sexual and asexual life cycle. Some coccidia are human pathogens, for example: Cryptosporidium: Cryptosporidiums has many species that are mammalian intestinal parasites.C. Parvum specie is a human pathogenic protozoa. Cryptosporidum has circle or ellipse shapes and nearly 4-6 mm. It is transmitted in warm seasons. Oocyst is obtained insexual life cycle that has 20% thin layer and 80% thick layer. Oocyst with thick layer is able to live a long time in nature. They are the third or forth of gastroentritis disease that have digestive disorder like anorexia, nausea, persistent diarrhoea, malabsorption and leanness. The disease forms choronic and acute stages and it is able to kill the immunodeficiency cases. Sometimes it has HIV symptoms similar to pneumonia and respiratory track infection. Laboratory diagnosis is based on Oocyst finding in stool exam and that shitter floatation and Cr (KOH2 are the best methods. Modified zyh-lnelson and fleocroum are the best staining methods too. This parasite is transmitted by zoonotic and Antroponotic origin. Molecular studies have shown two Genotypes (I&II. Genotype I is aquatic and II is zoonotic. The prevalence rate is 3% in infants and 10% in calves. Cyclospora: This parasite is novel and is bigger than cryptosporidium.It isn't known a clear life cycle but is transmitted by water, vegetables and fruits as raspberries. and mulberries. Human is a specific host. When a parasite is in the intestine it causes inflammatory reaction in Entrocyte.The patient shows watery diarrhoea with nausea, vomitting, pain, Stomach cramp, anorexia, malabsorption and cachexia. The disease period is 3 monthes in immunodeficiency cases but it is selflimited in normal cases. Autofluorescence characteristic is differential diagnosis, prevalence rate of disease is unknown. Isospora: This

  1. Antiprotozoan lead discovery by aligning dry and wet screening: prediction, synthesis, and biological assay of novel quinoxalinones.

    Science.gov (United States)

    Martins Alho, Miriam A; Marrero-Ponce, Yovani; Barigye, Stephen J; Meneses-Marcel, Alfredo; Machado Tugores, Yanetsy; Montero-Torres, Alina; Gómez-Barrio, Alicia; Nogal, Juan J; García-Sánchez, Rory N; Vega, María Celeste; Rolón, Miriam; Martínez-Fernández, Antonio R; Escario, José A; Pérez-Giménez, Facundo; Garcia-Domenech, Ramón; Rivera, Norma; Mondragón, Ricardo; Mondragón, Mónica; Ibarra-Velarde, Froylán; Lopez-Arencibia, Atteneri; Martín-Navarro, Carmen; Lorenzo-Morales, Jacob; Cabrera-Serra, Maria Gabriela; Piñero, Jose; Tytgat, Jan; Chicharro, Roberto; Arán, Vicente J

    2014-03-01

    which the individual QSAR outputs are the inputs of the aforementioned fusion approach. Finally, the fusion model was used for the identification of a novel generation of lead-like antiprotozoan compounds by using ligand-based virtual screening of 'available' small molecules (with synthetic feasibility) in our 'in-house' library. A new molecular subsystem (quinoxalinones) was then theoretically selected as a promising lead series, and its derivatives subsequently synthesized, structurally characterized, and experimentally assayed by using in vitro screening that took into consideration a battery of five parasite-based assays. The chemicals 11(12) and 16 are the most active (hits) against apicomplexa (sporozoa) and mastigophora (flagellata) subphylum parasites, respectively. Both compounds depicted good activity in every protozoan in vitro panel and they did not show unspecific cytotoxicity on the host cells. The described technical framework seems to be a promising QSAR-classifier tool for the molecular discovery and development of novel classes of broad-antiprotozoan-spectrum drugs, which may meet the dual challenges posed by drug-resistant parasites and the rapid progression of protozoan illnesses.

  2. Comparison of indirect ELISA based on recombinant protein NcSRS2 and IFAT for detection of Neospora caninum antibodies in sheep Comparação entre ELISA baseado no antígeno recombinante NcSRS2 e RIFI para detecção de anticorpos de Neospora caninum em ovinos

    Directory of Open Access Journals (Sweden)

    Renato Andreotti

    2009-06-01

    Full Text Available Neospora caninum, an Apicomplexan parasite that can causes abortion, is responsible for considerable economic and reproductive losses in livestock. The purpose of the present study was to determine whether recombinant NcSRS2 is a suitable indirect ELISA antigen for determining specific immune response to N. caninum in sheep. A total of 441 serum samples were subjected to IFAT and rNcSRS2 based-ELISA, with both tests performing similarly. The sensitivity and specificity of indirect ELISA were 98.6 and 98.3%, respectively. The kappa index shows 0.98 concordance between the two tests, which is considered excellent. Seroprevalences of 30.8 and 32.0% were detected by IFAT and indirect ELISA, respectively, showing these tests did not differ significantly on this measure (p > 0.05. Serological analysis showed that HisG tag was detected by Western Blotting recognizing rNcSRS2 protein. The potential value of rNcSRS2-based ELISA as a highly specific and sensitive tool for serological diagnosis is also supported by the strong agreement found between IFAT and ELISA. The results support the potential use of recombinant protein NcSRS2 as an antigen in indirect ELISA in sheep.Neospora caninum é um parasito Apicomplexa que pode causar abortos e é reconhecido como agente importante responsável por perdas econômicas e reprodutivas. Este estudo avaliou a proteína recombinante NcSRS2 como antígeno para ELISA indireto na determinação de resposta imune para N. caninum em ovinos. 441 amostras de soro foram analisadas por IFAT e ELISA indireto com rNcSRS2 e ambos os testes revelaram comportamento similar. A sensibilidade e especificidade de ELISA indireto foram 98,6 e 98,3%, respectivamente. O índice kappa mostrou uma concordância entre os dois testes com valor de 0,98, que é considerado excelente. Prevalências de 30,8 e 32,0% detectadas por IFAT e ELISA indireto, respectivamente, mostraram que os testes não diferiram significativamente nesse aspecto (P

  3. 我国鸟类原虫种类与感染状况研究进展%RESEARCH PROGRESS ON PROTOZOAN SPECIES AND INFECTION STATUS IN BIRDS IN CHINA

    Institute of Scientific and Technical Information of China (English)

    李榴佳; 黄兵; 舒凡帆; 吴有陵

    2013-01-01

    的防控和保护鸟类具有十分重要的指导意义。%Protozoa are a group of common parasites in birds and puts a threaten to public health in humans. In order to keep abreast of the recent protozoan species and infection status in birds in China, we have reviewed a lot of literatures about protozoan studies. In summary, 70 species of protozoa have been recorded in birds of China. These species are classified into 3 phyla (Apicomplexa, Sarcomastigophora, Sarcomastigophora), 4 classes (Sporozoa, Zoomastigophora, Lobosasida, Blastocystidea), 5 orders (Eucoccidiorida,Haemospororida, Trichomonadorida, Amoebida, Blastocystida), 9 families (Eimeiridae, Cryptosporidiidae, Sarcocystidae, Plasmodiidae, Leucocystozoidae, Monocercomonadidae, Trichomonadidae, Entamoebidae, Blastocystidae), and 12 genera. There are 23 species in Plasmodium, 20 species in Eimeria, 15 species in Leucocytozoon, 3 species in Cryptosporidium, 2 species in Isospora, and 1 species in each of Toxoplasm, Haemoproteus, Histomonas, Trichomonas, Entamoeba, Endolimax and Blastocystis. All in all, common protozoa in birds are coccidia, Plasmodium and Cryptosporidium. Coccidia, Plasmodium, Haemoproteus and Trichomonad often cause infection in birds and Cryptosporidium, Toxoplasma, Amoeba and Blastocystis can infect humans. Understanding on protozoan species and infections in birds may provide important guidance for the control of protozoosis in China.