brasilianum apicomplexa plasmodidae: Topics by Science.gov

Sample records for brasilianum apicomplexa plasmodidae

Natural infection of Plasmodium brasilianum in humans: Man and monkey share quartan malaria parasites in the Venezuelan Amazon.

PubMed

Lalremruata, Albert; Magris, Magda; Vivas-Martínez, Sarai; Koehler, Maike; Esen, Meral; Kempaiah, Prakasha; Jeyaraj, Sankarganesh; Perkins, Douglas Jay; Mordmüller, Benjamin; Metzger, Wolfram G

2015-09-01

The quartan malaria parasite Plasmodium malariae is the widest spread and best adapted human malaria parasite. The simian Plasmodium brasilianum causes quartan fever in New World monkeys and resembles P. malariae morphologically. Since the genetics of the two parasites are nearly identical, differing only in a range of mutations expected within a species, it has long been speculated that the two are the same. However, no naturally acquired infection with parasites termed as P. brasilianum has been found in humans until now. We investigated malaria cases from remote Yanomami indigenous communities of the Venezuelan Amazon and analyzed the genes coding for the circumsporozoite protein (CSP) and the small subunit of ribosomes (18S) by species-specific PCR and capillary based-DNA sequencing. Based on 18S rRNA gene sequencing, we identified 12 patients harboring malaria parasites which were 100% identical with P. brasilianum isolated from the monkey, Alouatta seniculus. Translated amino acid sequences of the CS protein gene showed identical immunodominant repeat units between quartan malaria parasites isolated from both humans and monkeys. This study reports, for the first time, naturally acquired infections in humans with parasites termed as P. brasilianum. We conclude that quartan malaria parasites are easily exchanged between humans and monkeys in Latin America. We hypothesize a lack of host specificity in mammalian hosts and consider quartan malaria to be a true anthropozoonosis. Since the name P. brasilianum suggests a malaria species distinct from P. malariae, we propose that P. brasilianum should have a nomenclatorial revision in case further research confirms our findings. The expansive reservoir of mammalian hosts discriminates quartan malaria from other Plasmodium spp. and requires particular research efforts.
Natural infection of Plasmodium brasilianum in humans: Man and monkey share quartan malaria parasites in the Venezuelan Amazon

PubMed Central

Lalremruata, Albert; Magris, Magda; Vivas-Martínez, Sarai; Koehler, Maike; Esen, Meral; Kempaiah, Prakasha; Jeyaraj, Sankarganesh; Perkins, Douglas Jay; Mordmüller, Benjamin; Metzger, Wolfram G.

2015-01-01

Background The quartan malaria parasite Plasmodium malariae is the widest spread and best adapted human malaria parasite. The simian Plasmodium brasilianum causes quartan fever in New World monkeys and resembles P. malariae morphologically. Since the genetics of the two parasites are nearly identical, differing only in a range of mutations expected within a species, it has long been speculated that the two are the same. However, no naturally acquired infection with parasites termed as P. brasilianum has been found in humans until now. Methods We investigated malaria cases from remote Yanomami indigenous communities of the Venezuelan Amazon and analyzed the genes coding for the circumsporozoite protein (CSP) and the small subunit of ribosomes (18S) by species-specific PCR and capillary based-DNA sequencing. Findings Based on 18S rRNA gene sequencing, we identified 12 patients harboring malaria parasites which were 100% identical with P. brasilianum isolated from the monkey, Alouatta seniculus. Translated amino acid sequences of the CS protein gene showed identical immunodominant repeat units between quartan malaria parasites isolated from both humans and monkeys. Interpretation This study reports, for the first time, naturally acquired infections in humans with parasites termed as P. brasilianum. We conclude that quartan malaria parasites are easily exchanged between humans and monkeys in Latin America. We hypothesize a lack of host specificity in mammalian hosts and consider quartan malaria to be a true anthropozoonosis. Since the name P. brasilianum suggests a malaria species distinct from P. malariae, we propose that P. brasilianum should have a nomenclatorial revision in case further research confirms our findings. The expansive reservoir of mammalian hosts discriminates quartan malaria from other Plasmodium spp. and requires particular research efforts. PMID:26501116
Merozoite surface protein-1 genetic diversity in Plasmodium malariae and Plasmodium brasilianum from Brazil.

PubMed

Guimarães, Lilian O; Wunderlich, Gerhard; Alves, João M P; Bueno, Marina G; Röhe, Fabio; Catão-Dias, José L; Neves, Amanda; Malafronte, Rosely S; Curado, Izilda; Domingues, Wilson; Kirchgatter, Karin

2015-11-16

The merozoite surface protein 1 (MSP1) gene encodes the major surface antigen of invasive forms of the Plasmodium erythrocytic stages and is considered a candidate vaccine antigen against malaria. Due to its polymorphisms, MSP1 is also useful for strain discrimination and consists of a good genetic marker. Sequence diversity in MSP1 has been analyzed in field isolates of three human parasites: P. falciparum, P. vivax, and P. ovale. However, the extent of variation in another human parasite, P. malariae, remains unknown. This parasite shows widespread, uneven distribution in tropical and subtropical regions throughout South America, Asia, and Africa. Interestingly, it is genetically indistinguishable from P. brasilianum, a parasite known to infect New World monkeys in Central and South America. Specific fragments (1 to 5) covering 60 % of the MSP1 gene (mainly the putatively polymorphic regions), were amplified by PCR in isolates of P. malariae and P. brasilianum from different geographic origin and hosts. Sequencing of the PCR-amplified products or cloned PCR fragments was performed and the sequences were used to construct a phylogenetic tree by the maximum likelihood method. Data were computed to give insights into the evolutionary and phylogenetic relationships of these parasites. Except for fragment 4, sequences from all other fragments consisted of unpublished sequences. The most polymorphic gene region was fragment 2, and in samples where this region lacks polymorphism, all other regions are also identical. The low variability of the P. malariae msp1 sequences of these isolates and the identification of the same haplotype in those collected many years apart at different locations is compatible with a low transmission rate. We also found greater diversity among P. brasilianum isolates compared with P. malariae ones. Lastly, the sequences were segregated according to their geographic origins and hosts, showing a strong genetic and geographic structure. Our data
Molecular Detection of Plasmodium malariae/Plasmodium brasilianum in Non-Human Primates in Captivity in Costa Rica.

PubMed

Fuentes-Ramírez, Alicia; Jiménez-Soto, Mauricio; Castro, Ruth; Romero-Zuñiga, Juan José; Dolz, Gaby

2017-01-01

One hundred and fifty-two blood samples of non-human primates of thirteen rescue centers in Costa Rica were analyzed to determine the presence of species of Plasmodium using thick blood smears, semi-nested multiplex polymerase chain reaction (SnM-PCR) for species differentiation, cloning and sequencing for confirmation. Using thick blood smears, two samples were determined to contain the Plasmodium malariae parasite, with SnM-PCR, a total of five (3.3%) samples were positive to P. malariae, cloning and sequencing confirmed both smear samples as P. malariae. One sample amplified a larger and conserved region of 18S rDNA for the genus Plasmodium and sequencing confirmed the results obtained microscopically and through SnM-PCR tests. Sequencing and construction of a phylogenetic tree of this sample revealed that the P. malariae/P. brasilianum parasite (GenBank KU999995) found in a howler monkey (Alouatta palliata) is identical to that recently reported in humans in Costa Rica. The SnM-PCR detected P. malariae/P. brasilianum parasite in different non-human primate species in captivity and in various regions of the southern Atlantic and Pacific coast of Costa Rica. The similarity of the sequences of parasites found in humans and a monkey suggests that monkeys may be acting as reservoirs of P.malariae/P. brasilianum, for which reason it is important, to include them in control and eradication programs.
Molecular Detection of Plasmodium malariae/Plasmodium brasilianum in Non-Human Primates in Captivity in Costa Rica

PubMed Central

Fuentes-Ramírez, Alicia; Jiménez-Soto, Mauricio; Castro, Ruth; Romero-Zuñiga, Juan José

2017-01-01

One hundred and fifty-two blood samples of non-human primates of thirteen rescue centers in Costa Rica were analyzed to determine the presence of species of Plasmodium using thick blood smears, semi-nested multiplex polymerase chain reaction (SnM-PCR) for species differentiation, cloning and sequencing for confirmation. Using thick blood smears, two samples were determined to contain the Plasmodium malariae parasite, with SnM-PCR, a total of five (3.3%) samples were positive to P. malariae, cloning and sequencing confirmed both smear samples as P. malariae. One sample amplified a larger and conserved region of 18S rDNA for the genus Plasmodium and sequencing confirmed the results obtained microscopically and through SnM-PCR tests. Sequencing and construction of a phylogenetic tree of this sample revealed that the P. malariae/P. brasilianum parasite (GenBank KU999995) found in a howler monkey (Alouatta palliata) is identical to that recently reported in humans in Costa Rica. The SnM-PCR detected P. malariae/P. brasilianum parasite in different non-human primate species in captivity and in various regions of the southern Atlantic and Pacific coast of Costa Rica. The similarity of the sequences of parasites found in humans and a monkey suggests that monkeys may be acting as reservoirs of P.malariae/P. brasilianum, for which reason it is important, to include them in control and eradication programs. PMID:28125696
Effectiveness of broadcast surveys in determining habitat use of Ferruginous Pygmy-owls (Glaucidium brasilianum) in southern Texas

Treesearch

Glenn A. Proudfoot; Jody L. Mays; Sam L. Beasom; Ralph Bingham

1997-01-01

We compared habitat information obtained from tracking 12 radio-tagged Ferruginous Pygmy-owls (Glaucidium brasilianum) (hereafter referred to as pygmy-owls) in southern Texas during 1995 and similar information from pygmy-owl response points to evaluate the effectiveness of broadcast surveys in determining pygmy-owl habitat use.
Migration of Apicomplexa Across Biological Barriers: The Toxoplasma and Plasmodium Rides

PubMed Central

Tardieux, Isabelle; Ménard, Robert

2008-01-01

The invasive stages of Apicomplexa parasites, called zoites, have been largely studied in in vitro systems, with a special emphasis on their unique gliding and host cell invasive capacities. In contrast, the means by which these parasites reach their destination in their hosts are still poorly understood. We summarize here our current understanding of the cellular basis of in vivo parasitism by two well-studied Apicomplexa zoites, the Toxoplasma tachyzoite and the Plasmodium sporozoite. Despite being close relatives, these two zoites use different strategies to reach their goal and establish infection. PMID:18194412
The complete mitochondrial genome sequence of Eimeria innocua (Eimeriidae, Coccidia, Apicomplexa).

PubMed

Hafeez, Mian Abdul; Vrba, Vladimir; Barta, John Robert

2016-07-01

The complete mitochondrial genome of Eimeria innocua KR strain (Eimeriidae, Coccidia, Apicomplexa) was sequenced. This coccidium infects turkeys (Meleagris gallopavo), Bobwhite quails (Colinus virginianus), and Grey partridges (Perdix perdix). Genome organization and gene contents were comparable with other Eimeria spp. infecting galliform birds. The circular-mapping mt genome of E. innocua is 6247 bp in length with three protein-coding genes (cox1, cox3, and cytb), 19 gene fragments encoding large subunit (LSU) rRNA and 14 gene fragments encoding small subunit (SSU) rRNA. Like other Apicomplexa, no tRNA was encoded. The mitochondrial genome of E. innocua confirms its close phylogenetic affinities to Eimeria dispersa.
Organochlorine Pesticides in the Ferruginous Pygmy Owl (Glaucidium brasilianum) in Chiapas, Mexico.

PubMed

Arrona-Rivera, Alicia E; Enríquez, Paula L; García-Feria, Luis M; Orellana, Sergio Alvarado; von Osten, Jaime Rendón

2016-09-01

Concentrations of organochlorine pesticides were quantified in samples of feathers (n = 17) and blood (n = 15) of the ferruginous pygmy owl (Glaucidium brasilianum). The individuals were captured near the Protected Natural Area Cerro Sonsonate, Chiapas, Mexico, between February and June 2014. In both tissues, pesticides belonging to seven organochlorine chemical families were detected. However, the organochlorine pesticide concentrations differed between feathers and blood. The highest concentrations of hexachlorocyclohexanes were found in feathers (0.63 ± 0.89 μg/g), whereas the highest concentrations of ΣDrines were found in blood (0.31 ± 0.47 μg/mL). By using the summed concentrations for each of the seven families of pesticides found in feathers, we did not find any significant correlation between the pesticides and pectoral muscle or body weight (p > 0.15). The ΣDDT group was the only pesticide family that showed a positive correlation with owl body weight (r = 0.60, p = 0.05); the concentrations of these pesticides were also high in feather and blood tissues (r = 0.87, p = 0.02). Our results confirm that ferruginous pygmy owls in the study area are exposed to these pesticides.
The Apicomplexa-specific glucosamine-6-phosphate N-acetyltransferase gene family encodes a key enzyme for glycoconjugate synthesis with potential as therapeutic target.

PubMed

Cova, Marta; López-Gutiérrez, Borja; Artigas-Jerónimo, Sara; González-Díaz, Aida; Bandini, Giulia; Maere, Steven; Carretero-Paulet, Lorenzo; Izquierdo, Luis

2018-03-05

Apicomplexa form a phylum of obligate parasitic protozoa of great clinical and veterinary importance. These parasites synthesize glycoconjugates for their survival and infectivity, but the enzymatic steps required to generate the glycosylation precursors are not completely characterized. In particular, glucosamine-phosphate N-acetyltransferase (GNA1) activity, needed to produce the essential UDP-N-acetylglucosamine (UDP-GlcNAc) donor, has not been identified in any Apicomplexa. We scanned the genomes of Plasmodium falciparum and representatives from six additional main lineages of the phylum for proteins containing the Gcn5-related N-acetyltransferase (GNAT) domain. One family of GNAT-domain containing proteins, composed by a P. falciparum sequence and its six apicomplexan orthologs, rescued the growth of a yeast temperature-sensitive GNA1 mutant. Heterologous expression and in vitro assays confirmed the GNA1 enzymatic activity in all lineages. Sequence, phylogenetic and synteny analyses suggest an independent origin of the Apicomplexa-specific GNA1 family, parallel to the evolution of a different GNA1 family in other eukaryotes. The inability to disrupt an otherwise modifiable gene target suggests that the enzyme is essential for P. falciparum growth. The relevance of UDP-GlcNAc for parasite viability, together with the independent evolution and unique sequence features of Apicomplexa GNA1, highlights the potential of this enzyme as a selective therapeutic target against apicomplexans.
Calcium signaling in closely related protozoan groups (Alveolata): non-parasitic ciliates (Paramecium, Tetrahymena) vs. parasitic Apicomplexa (Plasmodium, Toxoplasma).

PubMed

Plattner, H; Sehring, I M; Mohamed, I K; Miranda, K; De Souza, W; Billington, R; Genazzani, A; Ladenburger, E-M

2012-05-01

The importance of Ca2+-signaling for many subcellular processes is well established in higher eukaryotes, whereas information about protozoa is restricted. Recent genome analyses have stimulated such work also with Alveolates, such as ciliates (Paramecium, Tetrahymena) and their pathogenic close relatives, the Apicomplexa (Plasmodium, Toxoplasma). Here we compare Ca2+ signaling in the two closely related groups. Acidic Ca2+ stores have been characterized in detail in Apicomplexa, but hardly in ciliates. Two-pore channels engaged in Ca2+-release from acidic stores in higher eukaryotes have not been stingently characterized in either group. Both groups are endowed with plasma membrane- and endoplasmic reticulum-type Ca2+-ATPases (PMCA, SERCA), respectively. Only recently was it possible to identify in Paramecium a number of homologs of ryanodine and inositol 1,3,4-trisphosphate receptors (RyR, IP3R) and to localize them to widely different organelles participating in vesicle trafficking. For Apicomplexa, physiological experiments suggest the presence of related channels although their identity remains elusive. In Paramecium, IP3Rs are constitutively active in the contractile vacuole complex; RyR-related channels in alveolar sacs are activated during exocytosis stimulation, whereas in the parasites the homologous structure (inner membrane complex) may no longer function as a Ca2+ store. Scrutinized comparison of the two closely related protozoan phyla may stimulate further work and elucidate adaptation to parasitic life. See also "Conclusions" section. Copyright © 2012 Elsevier Ltd. All rights reserved.
Gene Discovery in the Apicomplexa as Revealed by EST Sequencing and Assembly of a Comparative Gene Database

PubMed Central

Li, Li; Brunk, Brian P.; Kissinger, Jessica C.; Pape, Deana; Tang, Keliang; Cole, Robert H.; Martin, John; Wylie, Todd; Dante, Mike; Fogarty, Steven J.; Howe, Daniel K.; Liberator, Paul; Diaz, Carmen; Anderson, Jennifer; White, Michael; Jerome, Maria E.; Johnson, Emily A.; Radke, Jay A.; Stoeckert, Christian J.; Waterston, Robert H.; Clifton, Sandra W.; Roos, David S.; Sibley, L. David

2003-01-01

Large-scale EST sequencing projects for several important parasites within the phylum Apicomplexa were undertaken for the purpose of gene discovery. Included were several parasites of medical importance (Plasmodium falciparum, Toxoplasma gondii) and others of veterinary importance (Eimeria tenella, Sarcocystis neurona, and Neospora caninum). A total of 55,192 ESTs, deposited into dbEST/GenBank, were included in the analyses. The resulting sequences have been clustered into nonredundant gene assemblies and deposited into a relational database that supports a variety of sequence and text searches. This database has been used to compare the gene assemblies using BLAST similarity comparisons to the public protein databases to identify putative genes. Of these new entries, ∼15%–20% represent putative homologs with a conservative cutoff of p < 10−9, thus identifying many conserved genes that are likely to share common functions with other well-studied organisms. Gene assemblies were also used to identify strain polymorphisms, examine stage-specific expression, and identify gene families. An interesting class of genes that are confined to members of this phylum and not shared by plants, animals, or fungi, was identified. These genes likely mediate the novel biological features of members of the Apicomplexa and hence offer great potential for biological investigation and as possible therapeutic targets. [The sequence data from this study have been submitted to dbEST division of GenBank under accession nos.: Toxoplasma gondii: –, –, –, –, – , –, –, –, –. Plasmodium falciparum: –, –, –, –. Sarcocystis neurona: , , , , , , , , , , , , , –, –, –, –, –. Eimeria tenella: –, –, –, –, –, –, –, –, – , –, –, –, –, –, –, –, –, –, –, –. Neospora caninum: –, –, , – , –, –.] PMID:12618375
First report of Calyptospora sp. (Apicomplexa, Calyptosporidae) in forage characid fish from the Três Marias Reservoir, São Francisco Basin, Brazil.

PubMed

de Albuquerque, Marcia Cavalcanti; de Carvalho Brasil-Sato, Marilia

2010-05-01

Coccidians are parasitic protozoans, and Calyptospora is an important genus of coccidia found in freshwater and marine fish of the Americas. This paper describes Calyptospora sp. that were found parasitizing the liver and intestine of Triportheus guentheri and the intestine of Tetragonopterus chalceus, two forage fish species from the Três Marias Reservoir, Upper São Francisco River, State of Minas Gerais, Brazil. Apicomplexa found in the São Francisco Basin are reported here for the first time. Copyright (c) 2010 Elsevier GmbH. All rights reserved.
Distribution and Evolution of Peroxisomes in Alveolates (Apicomplexa, Dinoflagellates, Ciliates)

PubMed Central

Ludewig-Klingner, Ann-Kathrin; Michael, Victoria; Jarek, Michael; Brinkmann, Henner

2018-01-01

Abstract The peroxisome was the last organelle to be discovered and five decades later it is still the Cinderella of eukaryotic compartments. Peroxisomes have a crucial role in the detoxification of reactive oxygen species, the beta-oxidation of fatty acids, and the biosynthesis of etherphospholipids, and they are assumed to be present in virtually all aerobic eukaryotes. Apicomplexan parasites including the malaria and toxoplasmosis agents were described as the first group of mitochondriate protists devoid of peroxisomes. This study was initiated to reassess the distribution and evolution of peroxisomes in the superensemble Alveolata (apicomplexans, dinoflagellates, ciliates). We established transcriptome data from two chromerid algae (Chromera velia, Vitrella brassicaformis), and two dinoflagellates (Prorocentrum minimum, Perkinsus olseni) and identified the complete set of essential peroxins in all four reference species. Our comparative genome analysis provides unequivocal evidence for the presence of peroxisomes in Toxoplasma gondii and related genera. Our working hypothesis of a common peroxisomal origin of all alveolates is supported by phylogenetic analyses of essential markers such as the import receptor Pex5. Vitrella harbors the most comprehensive set of peroxisomal proteins including the catalase and the glyoxylate cycle and it is thus a promising model organism to investigate the functional role of this organelle in Apicomplexa. PMID:29202176
A central role for phosphatidic acid as a lipid mediator of regulated exocytosis in apicomplexa.

PubMed

Bullen, Hayley E; Soldati-Favre, Dominique

2016-08-01

Lipids are commonly known for the structural roles they play, however, the specific contribution of different lipid classes to wide-ranging signalling pathways is progressively being unravelled. Signalling lipids and their associated effector proteins are emerging as significant contributors to a vast array of effector functions within cells, including essential processes such as membrane fusion and vesicle exocytosis. Many phospholipids have signalling capacity, however, this review will focus on phosphatidic acid (PA) and the enzymes implicated in its production from diacylglycerol (DAG) and phosphatidylcholine (PC): DGK and PLD respectively. PA is a negatively charged, cone-shaped lipid identified as a key mediator in specific membrane fusion and vesicle exocytosis events in a variety of mammalian cells, and has recently been implicated in specialised secretory organelle exocytosis in apicomplexan parasites. This review summarises the recent work implicating a role for PA regulation in exocytosis in various cell types. We will discuss how these signalling events are linked to pathogenesis in the phylum Apicomplexa. © 2016 Federation of European Biochemical Societies.
A new species of Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae) from Alectoris barbara (Aves: Phasianidae) from the Canary Islands (Spain).

PubMed

Fernández-Alvarez, A; Modry, D; Foronda, P

2016-05-01

The present study was conducted with the objective of identifying the species of Eimeria present in a cynegetic farm. A new coccidian (Apicomplexa: Eimeriidae) species is described from Barbary partridge, Alectoris barbara, from the Canary Islands. Experimental infections were carried out in order to determine the prepatent period, sporulation time, site of infection, and morphology of endogenous stages. One species is described as new. Eimeria barbarae n. sp. has ellipsoidal oocysts, 20.0 × 14.4 (16-23 × 13-16) μm, with a shape-index (SI) of 1.39. Sporocysts are almond-shaped, 9.0 × 5.4 (6.5-11 × 4.5-6) μm, SI = 1.56. The endogenous development takes place along the intestine. The present study showed that E. barbarae causes severe pathologies in A. barbara chickens, with impact on their health condition. Control strategies needs to be implemented to reduce the loss due to coccidiosis at studied farm.
Molecular survey and microscopic examination of Hepatozoon Miller, 1908 (Apicomplexa: Adeleorina) in lacertid lizards from the western Mediterranean.

PubMed

Maia, João P M C; Perera, Ana; Harris, D James

2012-12-01

The genus Hepatozoon Miller, 1908 (Apicomplexa: Adeleorina) is composed of intracellular haemogregarine parasites that are widely distributed among all tetrapod groups. The present study combines microscopic and molecular data on haemogregarine parasites from lizards in the western Mediterranean. We screened tissue samples and examined blood smears for the presence of species of Hepatozoon from four lizards, namely Algyroides marchi Valverde, endemic to Southeast Spain, Podarcis bocagei Seoane from Spain and Portugal, P hispanica Steindachner from Spain, and P lilfordi Günther from Cabrera, Balearic Islands (Spain). Our results show that prevalence and intensity of Hepatozoon parasites vary between and within lizard species from different regions. Algyroides marchi and P bocagei from Spain had the lowest values, whereas P hispanica had the highest. Phylogeny based on 18S rRNA gene sequences indicates that most of the new Hepatozoon sequences are part of a clade exclusive from North African and Iberian lizards, except for a single P bocagei isolate that is found related to another clade including isolates from other reptile host species and rodents. Interestingly, isolates from Algyroides form a distinct monophyletic subgroup, which could be a signal of strict host-specificity within this host genus.
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

NASA Astrophysics Data System (ADS)

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.
Identification of Plasmodium spp. in Neotropical primates of Maranhense Amazon in Northeast Brazil.

PubMed

Figueiredo, Mayra Araguaia Pereira; Di Santi, Silvia Maria; Manrique, Wilson Gómez; André, Marcos Rogério; Machado, Rosangela Zacarias

2017-01-01

In the Brazilian Amazon region, malaria caused by Plasmodium malariae is considered to be a zoonosis because of cross-transfer of the parasite between humans and Neotropical primates. To contribute information on this issue, we investigated occurrences of natural infection with Plasmodium sp. among Neotropical primates in the Maranhense Amazon (Amazon region of the state of Maranhão), in the northeastern region of Brazil. Blood samples were collected from 161 Neotropical primates of six species that were caught in an environmental reserve (Sítio Aguahy) and from captive primates (CETAS-Wildlife Screening Center, municipality of São Luís), in Maranhão. Plasmodium sp. was diagnosed based on light microscopy, PCR, qPCR and LAMP for amplification of the 18S rRNA gene. Serum samples were also assayed by means of indirect immunofluorescence for IgG antibodies against P. malariae/P. brasilianum, P. falciparum and P. berghei. Parasites were detected through light microscopy on five slides from captive primates (four Sapajus spp. and one Callithrix jacchus). In the molecular tests, 34.16% (55/161) and 29.81% (48/161) of the animals sampled were positive in the qPCR and PCR assays, respectively. In the PCR, 47/48 animals were positive for P. malariae/P. brasilianum; of these, eight were free-living primates and 39 from CETAS, São Luís. One sample showed a band in the genus-specific reaction, but not in the second PCR reaction. Anti-P. malariae/P. brasilianum IgG antibodies were detected in four serum samples from Sapajus spp. in captivity. In this study, circulation of P. malariae/P. brasilianum in Neotropical primates was confirmed, with low levels of parasitemia and low levels of antibodies. The importance of these animals as reservoirs of human malaria in the region studied is still unknown. This scenario has an impact on control and elimination of malaria in this region.
Elongation Factor-1a is a novel protein associated with host cell invasion and a potential protective antigen of Cryptosporidium parvum*

USDA-ARS?s Scientific Manuscript database

The phylum Apicomplexa comprises obligate intracellular parasites that infect vertebrates. All invasive forms of Apicomplexa possess a unique complex of organelles at the anterior end, referred to as the apical complex, which is involved in host cell invasion. Previously, we generated the chicken m...

Natural Plasmodium infection in monkeys in the state of Rondônia (Brazilian Western Amazon)

PubMed Central

2013-01-01

Background Simian malaria is still an open question concerning the species of Plasmodium parasites and species of New World monkeys susceptible to the parasites. In addition, the lingering question as to whether these animals are reservoirs for human malaria might become important especially in a scenario of eradication of the disease. To aid in the answers to these questions, monkeys were surveyed for malaria parasite natural infection in the Amazonian state of Rondônia, Brazil, a state with intense environmental alterations due to human activities, which facilitated sampling of the animals. Methods Parasites were detected and identified in DNA from blood of monkeys, by PCR with primers for the 18S rRNA, CSP and MSP1 genes and sequencing of the amplified fragments. Multiplex PCR primers for the 18S rRNA genes were designed for the parasite species Plasmodium falciparum and Plasmodium vivax, Plasmodium malariae/Plasmodium brasilianum and Plasmodium simium. Results An overall infection rate of 10.9% was observed or 20 out 184 monkey specimens surveyed, mostly by P. brasilianum. However, four specimens of monkeys were found infected with P. falciparum, two of them doubly infected with P. brasilianum and P. falciparum. In addition, a species of monkey of the family Aotidae, Aotus nigriceps, is firstly reported here naturally infected with P. brasilianum. None of the monkeys surveyed was found infected with P. simium/P. vivax. Conclusion The rate of natural Plasmodium infection in monkeys in the Brazilian state of Rondônia is in line with previous surveys of simian malaria in the Amazon region. The fact that a monkey species was found that had not previously been described to harbour malaria parasites indicates that the list of monkey species susceptible to Plasmodium infection is yet to be completed. Furthermore, finding monkeys in the region infected with P. falciparum clearly indicates parasite transfer from humans to the animals. Whether this parasite can be
A Floral Transcriptome for Hippeastrum (Amaryllidaceae)

USDA-ARS?s Scientific Manuscript database

Two transcriptomes have been constructed from floral tissue of two Hippeastrum (Amaryllidaceae) species, H. brasilianum (Traub & J.L.Doran) Dutilh and H. papilio (Ravenna) Van Scheepan. The former has fragrant flowers, while flowers of the latter do not produce floral fragrance. RNA was isolated a...
Molecular analyses on host-seeking black flies (Diptera: Simuliidae) reveal a diverse assemblage of Leucocytozoon (Apicomplexa: Haemospororida) parasites in an alpine ecosystem.

PubMed

Murdock, Courtney C; Adler, Peter H; Frank, Jared; Perkins, Susan L

2015-06-25

Molecular studies have suggested that the true diversity of Leucocytozoon (Apicomplexa: Haemospororida) species well exceeds the approximately 35 currently described taxa. Further, the degree of host-specificity may vary substantially among lineages. Parasite distribution can be influenced by the ability of the parasite to infect a host, vector preferences for certain avian hosts, or other factors such as microhabitat requirements that increase the probability that vertebrate hosts and vectors are in frequent contact with each other. Whereas most studies of haemosporidians have focused on passerine hosts, sampling vectors in the same habitats may allow the detection of other lineages affecting other hosts. We sampled abundant, ornithophilic black flies (Simuliidae) across a variety of sites and habitats in the Colorado Rocky Mountains throughout the summer of 2007. Black flies were screened with PCR using Leucocytozoon-specific primers that amplify a portion of the cytochrome b gene, and the sequences were compared to the haplotypes in the MalAvi database. Infections of Leucocytozoon from birds sampled in the same area were also included. We recovered 33 unique haplotypes from the black flies in this study area, which represented a large phylogenetic diversity of Leucocytozoon parasites. However, there were no clear patterns of avian host species or geography for the distribution of Leucocytozoon haplotypes in the phylogeny. Sampling host-seeking vectors is a useful way to obtain a wide variety of avian haemosporidian haplotypes from a given area and may prove useful for understanding the global patterns of host, parasite, and vector associations of these ubiquitous and diverse parasites.
Chapter 1: The cactus ferruginous pygmy-owl: Taxonomy, distribution, and natural history

Treesearch

Jean-Luc E. Cartron; W. Scott Richardson; Glenn A. Proudfoot

2000-01-01

The cactus ferruginous pygmy-owl (Glaucidium brasilianum cactorum) is a small, cryptic owl that is often difficult to observe. Its natural history and conservation needs are poorly understood. Despite ongoing research in Texas and Arizona, the available information remains limited. In addition, factors influencing demographics (e.g., habitat...
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?

PubMed

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.
Identification and analysis of Eimeria nieschulzi gametocyte genes reveal splicing events of gam genes and conserved motifs in the wall-forming proteins within the genus Eimeria (Coccidia, Apicomplexa)

PubMed Central

Wiedmer, Stefanie; Erdbeer, Alexander; Volke, Beate; Randel, Stephanie; Kapplusch, Franz; Hanig, Sacha; Kurth, Michael

2017-01-01

The genus Eimeria (Apicomplexa, Coccidia) provides a wide range of different species with different hosts to study common and variable features within the genus and its species. A common characteristic of all known Eimeria species is the oocyst, the infectious stage where its life cycle starts and ends. In our study, we utilized Eimeria nieschulzi as a model organism. This rat-specific parasite has complex oocyst morphology and can be transfected and even cultivated in vitro up to the oocyst stage. We wanted to elucidate how the known oocyst wall-forming proteins are preserved in this rodent Eimeria species compared to other Eimeria. In newly obtained genomics data, we were able to identify different gametocyte genes that are orthologous to already known gam genes involved in the oocyst wall formation of avian Eimeria species. These genes appeared putatively as single exon genes, but cDNA analysis showed alternative splicing events in the transcripts. The analysis of the translated sequence revealed different conserved motifs but also dissimilar regions in GAM proteins, as well as polymorphic regions. The occurrence of an underrepresented gam56 gene version suggests the existence of a second distinct E. nieschulzi genotype within the E. nieschulzi Landers isolate that we maintain. PMID:29210668
Chapter 6: Research needs for the conservation of the cactus ferruginous pygmy-owl in Arizona

Treesearch

Jean-Luc E. Cartron; W. Scott Richardson; Deborah M. Finch; David J. Krueper

2000-01-01

In this chapter, we describe research needs for the conservation of the cactus ferruginous pygmy-owl (Glaucidium brasilianum cactorum) in Arizona. Estimates of population size, structure, and dynamics, as well as demographic data, are needed for the recovery team to formulate sound population objectives. Habitat loss due to residential development...
Chapter 3: The status of the cactus ferruginous pygmy-owl in Arizona: Population surveys and habitat assessment

Treesearch

W. Scott Richardson; Jean-Luc E. Cartron; David J. Krueper; Lauren Turner; Thomas H. Skinner

2000-01-01

In 1993, the Arizona Game and Fish Department (AGFD) began formal population surveys in an attempt to document the numbers and distribution of cactus ferruginous pygmy-owls (Glaucidium brasilianum cactorum) in Arizona. Surveys were initiated to gather information on this little-known subspecies which was considered for listing at the time. Prior to...
The Hsp40 proteins of Plasmodium falciparum and other apicomplexa: regulating chaperone power in the parasite and the host.

PubMed

Botha, M; Pesce, E-R; Blatch, G L

2007-01-01

Extensive structural and functional remodelling of Plasmodium falciparum (malaria)-infected erythrocytes follows the export of a range of proteins of parasite origin (exportome) across the parasitophorous vacuole into the host erythrocyte. The genome of P. falciparum encodes a diverse chaperone complement including at least 43 members of the heat shock protein 40kDa (Hsp40) family, and six members of the heat shock protein 70kDa (Hsp70) family. Nearly half of the Hsp40 proteins of P. falciparum are predicted to contain a PEXEL/HT (Plasmodium export element/host targeting signal) sequence motif, and hence are likely to be part of the exportome. In this review we critically evaluate the classification, sequence similarity and clustering, and possible interactors of the P. falciparum Hsp40 chaperone machinery. In addition to the types I, II and III Hsp40 proteins all exhibiting the signature J-domain, the P. falciparum genome also encodes a number of specialized Hsp40 proteins with a J-like domain, which we have categorized as type IV Hsp40 proteins. Analysis of the potential P. falciparum Hsp40 protein interaction network revealed connections predominantly with cytoskeletal and membrane proteins, transcriptional machinery, DNA repair and replication machinery, translational machinery, the proteasome and proteolytic enzymes, and enzymes involved in cellular physiology. Comparison of the Hsp40 proteins of P. falciparum to those of other apicomplexa reveals that most of the proteins (especially the PEXEL/HT-containing proteins) are unique to P. falciparum. Furthermore, very few of the P. falciparum Hsp40 proteins have human homologs, except for those proteins implicated in fundamental biological processes. Our analysis suggests that P. falciparum has evolved an expanded and specialized Hsp40 protein machinery to enable it successfully to invade and remodel the human erythrocyte, and we propose a model in which these proteins are involved in chaperone
Chapter 2: A historical perspective on the population decline of the cactus ferruginous pygmy-owl in Arizona

Treesearch

R. Roy Johnson; Jean-Luc E. Cartron; Lois T. Haight; Russell B. Duncan; Kenneth J. Kingsley

2000-01-01

The cactus ferruginous pygmy-owl (Glaucidium brasilianum cactorum) was discovered in the U.S. by Bendire in 1872 in the Tucson area (Coues 1872). During the next five decades, naturalists collected many specimens of this owl and typically described the subspecies as common or fairly common along some streams and rivers of central and southern Arizona...
Introduction

Treesearch

Jean-Luc E. Finch Cartron; Deborah M.

2000-01-01

In March 1997, the U.S. Fish and Wildlife Service listed the Arizona population of the cactus ferruginous pygmy-owl (Glaucidium brasilianum cactorum) as endangered under the Endangered Species Act (U.S. Fish and Wildlife 1997). Federal listing for the owl in Arizona resulted from a petition submitted in 1992 to the U.S. Fish and Wildlife Service (...
Chapter 4: The ferruginous pygmy-owl in the tropics and at the northern end of its range: Habitat relations and requirements

Treesearch

Jean-Luc E. Cartron; Scott H. Stoleson; Stephen M. Russell; Glenn A. Proudfoot; W. Scott Richardson

2000-01-01

The habitat needs of the ferruginous pygmy-owl (Glaucidium brasilianum) are poorly understood. In the tropics, this common bird of prey inhabits many distinct vegetation communities or environments (e.g., Monroe 1968, Meyer de Schauensee 1970, Stiles and Skutch 1989, Sick 1993). A resident of woodlands and open forests, it is also found in the open,...
Molecular assessment of Hepatozoon (Apicomplexa: Adeleorina) infections in wild canids and rodents from north Africa, with implications for transmission dynamics across taxonomic groups.

PubMed

Maia, João P; Alvares, Francisco; Boratyński, Zbyszek; Brito, José C; Leite, João V; Harris, D James

2014-10-01

Parasites play a major role in ecosystems, and understanding of host-parasite interactions is important for predicting parasite transmission dynamics and epidemiology. However, there is still a lack of knowledge about the distribution, diversity, and impact of parasites in wildlife, especially from remote areas. Hepatozoon is a genus of apicomplexan parasites that is transmitted by ingestion of infected arthropod vectors. However, alternative modes of transmission have been identified such as trophic transmission. Using the 18S rRNA gene as a marker, we provide an assessment of Hepatozoon prevalence in six wild canid and two rodent species collected between 2003 and 2012 from remote areas in North Africa. By combining this with other predator-prey systems in a phylogenetic framework, we investigate Hepatozoon transmission dynamics in distinct host taxa. Prevalence was high overall among host species (African jerboa Jaculus jaculus [17/47, 36%], greater Egyptian jerboa Jaculus orientalis [5/7, 71%], side-striped jackal Canis adustus [1/2, 50%], golden jackal Canis aureus [6/32, 18%], pale fox Vulpes pallida [14/28, 50%], Rüppell's fox Vulpes rueppellii [6/11, 55%], red fox Vulpes vulpes [8/16, 50%], and fennec fox Vulpes zerda [7/11, 42%]). Phylogenetic analysis showed further evidence of occasional transmission of Hepatozoon lineages from prey to canid predators, which seems to occur less frequently than in other predator-prey systems such as between snakes and lizards. Due to the complex nature of the Hepatozoon lifecycle (heteroxenous and vector-borne), future studies on these wild host species need to clarify the dynamics of alternative modes of Hepatozoon transmission and identify reservoir and definitive hosts in natural populations. We also detected putative Babesia spp. (Apicomplexa: Piroplasmida) infections in two canid species from this region, V. pallida (1/28) and V. zerda (1/11).
Molecular Genetic Manipulation of Sarcocystis neurona.

PubMed

Howe, Daniel K; Yeargan, Michelle; Simpson, Landon; Dangoudoubiyam, Sriveny

2018-02-22

Sarcocystis neurona is a member of the important phylum Apicomplexa and the primary cause of equine protozoal myeloencephalitis (EPM). Moreover, S. neurona is the best-studied species in the genus Sarcocystis, one of the most successful parasite taxa, as virtually all vertebrate animals may be infected by at least one species. Consequently, scientific investigation of S. neurona will aid in the control of EPM and neurologic disease in sea mammals, while also improving our understanding of a prominent branch on the apicomplexan phylogenetic tree. These protocols describe methods that expand the capabilities to study this prominent member of the Apicomplexa. © 2018 by John Wiley & Sons, Inc. Copyright © 2018 John Wiley & Sons, Inc.
Identification of Eimeria acervulina conoid antigen using chicken monoclonal antibody and liquid chromatography coupled to mass spectrometry

USDA-ARS?s Scientific Manuscript database

Protozoan parasites of the phylum Apicomplexa include a large number of medically important species. Among them, Toxoplasma gondii, Plasmodium, Cryptosporidium that cause watery diarrhea and mortality in humans and livestock, and Eimeria which induces gastrointestinal disorder in livestock and poul...
Dissecting the interface between apicomplexan parasite and host cell: Insights from a divergent AMARON2 pair

USDA-ARS?s Scientific Manuscript database

Plasmodium falciparum and Toxoplasma gondii are widely studied parasites in phylum Apicomplexa and the etiological agents of severe human malaria and toxoplasmosis, respectively. These intracellular pathogens have evolved a sophisticated invasion strategy that relies on delivery of proteins into the...
Comparative bioinformatics analysis of transcription factor genes indicates conservation of key regulatory domains among babesia bovis, babesia microti and theileria equi.

USDA-ARS?s Scientific Manuscript database

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...
Eimeria-induced chicken cNK-2 is an anti-infective host defense peptide and an immunomodulator of host innate immunity

USDA-ARS?s Scientific Manuscript database

Avian coccidiosis is one of the most widespread infectious diseases of chickens. The etiologic agent of avian coccidiosis is Eimeria, a genus of eukaryotic obligate intracellular parasites belonging to the phylum Apicomplexa. Clinical manifestations of infection include damage to the intestinal epit...
Eugregarines reduce susceptibility of the hide beetle, Dermestes maculatus, to apicomplexan pathogens and retard larval development

USDA-ARS?s Scientific Manuscript database

Eugregarines are abundant in a great diversity of invertebrates, and yet their relationships with their hosts are subject to controversy and confusion. We tested the effect of the eugregarine, Pyxinia crystalligera, on growth, development, and susceptibility to two Apicomplexa pathogens of the hide ...
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.

PubMed

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.

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

USDA-ARS?s Scientific Manuscript database

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...
Immune Response to Cryptosporidiosis in Philippine Children

DTIC Science & Technology

1990-01-01

Pro- fection: present knowledge and future directions. duction of monoclonal antibodies specific for Lancet /.: 688-69 1. 111:83 165894 Eimeria ...111:73035602 inhibition of growth of Eimeria bovis and Ei- 3 1. van Asbeck BS, Verhoef J1. 1983. Iron and host meria papillata (Apicomplexa) in
Sarcocystosis of animals and humans

USDA-ARS?s Scientific Manuscript database

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...
Functional and phylogenetic evidence of a bacterial origin for the first enzyme in sphingolipid biosynthesis in a phylum of eukaryotic protozoan parasites.

PubMed

Mina, John G; Thye, Julie K; Alqaisi, Amjed Q I; Bird, Louise E; Dods, Robert H; Grøftehauge, Morten K; Mosely, Jackie A; Pratt, Steven; Shams-Eldin, Hosam; Schwarz, Ralph T; Pohl, Ehmke; Denny, Paul W

2017-07-21

Toxoplasma gondii is an obligate, intracellular eukaryotic apicomplexan protozoan parasite that can cause fetal damage and abortion in both animals and humans. Sphingolipids are essential and ubiquitous components of eukaryotic membranes that are both synthesized and scavenged by the Apicomplexa. Here we report the identification, isolation, and analyses of the Toxoplasma serine palmitoyltransferase, an enzyme catalyzing the first and rate-limiting step in sphingolipid biosynthesis: the condensation of serine and palmitoyl-CoA. In all eukaryotes analyzed to date, serine palmitoyltransferase is a highly conserved heterodimeric enzyme complex. However, biochemical and structural analyses demonstrated the apicomplexan orthologue to be a functional, homodimeric serine palmitoyltransferase localized to the endoplasmic reticulum. Furthermore, phylogenetic studies indicated that it was evolutionarily related to the prokaryotic serine palmitoyltransferase, identified in the Sphingomonadaceae as a soluble homodimeric enzyme. Therefore this enzyme, conserved throughout the Apicomplexa, is likely to have been obtained via lateral gene transfer from a prokaryote. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.
The Plasmodium selenoproteome

PubMed Central

Lobanov, Alexey V.; Delgado, Cesar; Rahlfs, Stefan; Novoselov, Sergey V.; Kryukov, Gregory V.; Gromer, Stephan; Hatfield, Dolph L.; Becker, Katja; Gladyshev, Vadim N.

2006-01-01

The use of selenocysteine (Sec) as the 21st amino acid in the genetic code has been described in all three major domains of life. However, within eukaryotes, selenoproteins are only known in animals and algae. In this study, we characterized selenoproteomes and Sec insertion systems in protozoan Apicomplexa parasites. We found that among these organisms, Plasmodium and Toxoplasma utilized Sec, whereas Cryptosporidium did not. However, Plasmodium had no homologs of known selenoproteins. By searching computationally for evolutionarily conserved selenocysteine insertion sequence (SECIS) elements, which are RNA structures involved in Sec insertion, we identified four unique Plasmodium falciparum selenoprotein genes. These selenoproteins were incorrectly annotated in PlasmoDB, were conserved in other Plasmodia and had no detectable homologs in other species. We provide evidence that two Plasmodium SECIS elements supported Sec insertion into parasite and endogenous selenoproteins when they were expressed in mammalian cells, demonstrating that the Plasmodium SECIS elements are functional and indicating conservation of Sec insertion between Apicomplexa and animals. Dependence of the plasmodial parasites on selenium suggests possible strategies for antimalarial drug development. PMID:16428245
Oxidative potential of some endophytic fungi using 1-indanone as a substrate.

PubMed

Fill, Taicia Pacheco; da Silva, Jose Vinicius; de Oliveira, Kleber Thiago; da Silva, Bianca Ferreira; Rodrigues-Fo, Edson

2012-06-01

The oxidative potential of the fungus Penicillium brasilianum, a strain isolated as an endophyte from a Meliaceae plant (Melia azedarach), was investigated using 1-indanone as a substrate to track the production of monooxygenases. The fungus produced the dihydrocoumarin from 1-indanone with the classical Baeyer-Villiger reaction regiochemistry, and (-)-(R)-3-hydroxy-1-indanone with 78% ee. Minor compounds resulting from lipase and SAM activities were also detected. The biotransformation procedures were also applied to a collection of Penicillium and Aspergillus fungi obtained from M. azedarach and Murraya paniculata. The results showed that Baeyer-Villiger were mostly active in fungi isolated from M. azedarach. Almost all of the fungi tested produced 3-hydroxy-1-indanone..
Phylogeny of the Haplosporidia (Eukaryota: Alveolata) based on small subunit ribosomal RNA gene sequence.

PubMed

Flores, B S; Siddall, M E; Burreson, E M

1996-08-01

The phylogenetic position of the phylum Haplosporidia was investigated with the complete small subunit rRNA gene sequences from 5 species in the phylum: Haplosporidium nelsoni and Haplosporidium costale, parasites of the eastern oyster Crassostrea virginica; Haplosporidium louisiana, a parasite of the mudcrab Panopeus herbstii; Minchinia teredinis, a parasite of shipworms (Teredo spp.) and Urosporidium crescens, a hyperparasite found in metacercariae of the trematode Megalophallus sp. in the blue crab, Callinectes sapidus. Multiple alignments of small subunit rRNA gene sequences included the 5 haplosporidian taxa and 14 taxa in the alveolate phyla Ciliophora, Dinoflagellida, and Apicomplexa. Maximum parsimony analysis placed the phylum Haplosporidia as a monophyletic group within the alveolate clade, as a taxon of equal rank with the other 3 alveolate phyla, and as a sister taxon to the clade composed of the phyla Dinoflagellida and Apicomplexa. Transversionally weighted parsimony placed the haplosporidians as a sister taxon to the ciliates. A separate analysis focused on the relationships of species in the genus Haplosporidium. Analyses were conducted with the haplosporidians as a functional ingroup, using each of the alveolate phyla individually as functional outgroups. The results indicated that species in the genus Haplosporidium do not form a monophyletic assemblage. As such, the present morphological criteria for distinguishing the genera Haplosporidium and Minchinia are insufficient.
Hepatozoon parasites (Apicomplexa: Adeleorina) in bats.

PubMed

Pinto, C Miguel; Helgen, Kristofer M; Fleischer, Robert C; Perkins, Susan L

2013-08-01

We provide the first evidence of Hepatozoon parasites infecting bats. We sequenced a short fragment of the 18S rRNA gene (~600 base pairs) of Hepatozoon parasites from 3 Hipposideros cervinus bats from Borneo. Phylogenies inferred by model-based methods place these Hepatozoon within a clade formed by parasites of reptiles, rodents, and marsupials. We discuss the scenario that bats might be common hosts of Hepatozoon.
Screening for Hepatozoon parasites in gerbils and potential predators in South Africa.

PubMed

Harris, D James; Pereira, Ana; Halajian, Ali; Luus-Powell, Wilmien J; Kunutu, Katlego D

2017-02-08

Samples of gerbils and their potential predators were screened for the presence of Hepatozoon parasites (Apicomplexa: Adeleorina) using both microscopic examination and sequencing of partial 18S rRNA sequences. Positive samples were compared to published sequences in a phylogenetic framework. The results indicate that genets can be infected with Hepatozoon felis. A Cape fox was infected with Hepatozoon canis, whereas the sequence from an infected rodent fell within a group of parasites primarily recovered from other rodents and snakes.
RNA in development: how ribonucleoprotein granules regulate the life cycles of pathogenic protozoa.

PubMed

Kramer, Susanne

2014-01-01

Ribonucleoprotein (RNP) granules are important posttranscriptional regulators of messenger RNA (mRNA) fate. Several types of RNP granules specifically regulate gene expression during development of multicellular organisms and are commonly referred to as germ granules. The function of germ granules is not entirely understood and probably diverse, but it is generally agreed that one main function is posttranscriptional regulation of gene expression during early development, when transcription is silent. One example is the translational repression of maternally derived mRNAs in oocytes. Here, I hope to show that the need for regulation of gene expression by RNP granules is not restricted to animal development, but plays an equally important role during the development of pathogenic protozoa. Apicomplexa and Trypanosomatidae have complex life cycles with frequent host changes. The need to quickly adapt gene expression to a new environment as well as the ability to suppress translation to survive latencies is critical for successful completion of life cycles. Posttranscriptional gene regulation is not necessarily simpler in protozoa. Apicomplexa surprise with the presence of micro RNA (miRNAs) and upstream open reading frames (µORFs). Trypanosomes have an unusually large repertoire of different RNP granule types. A better understanding of RNP granules in protozoa may help to gain insight into the evolutionary origin of RNP granules: Trypanosomes for example have two types of granules with interesting similarities to animal germ granules. © 2013 John Wiley & Sons, Ltd.
Phylogenetic analysis of apicomplexan parasites infecting commercially valuable species from the North-East Atlantic reveals high levels of diversity and insights into the evolution of the group.

PubMed

Xavier, Raquel; Severino, Ricardo; Pérez-Losada, Marcos; Gestal, Camino; Freitas, Rita; Harris, D James; Veríssimo, Ana; Rosado, Daniela; Cable, Joanne

2018-01-25

The Apicomplexa from aquatic environments are understudied relative to their terrestrial counterparts, and the seminal work assessing the phylogenetic relations of fish-infecting lineages is mostly based on freshwater hosts. The taxonomic uncertainty of some apicomplexan groups, such as the coccidia, is high and many genera were recently shown to be paraphyletic, questioning the value of strict morphological and ecological traits for parasite classification. Here, we surveyed the genetic diversity of the Apicomplexa in several commercially valuable vertebrates from the North-East Atlantic, including farmed fish. Most of the sequences retrieved were closely related to common fish coccidia of Eimeria, Goussia and Calyptospora. However, some lineages from the shark Scyliorhinus canicula were placed as sister taxa to the Isospora, Caryospora and Schellakia group. Additionally, others from Pagrus caeruleostictus and Solea senegalensis belonged to an unknown apicomplexan group previously found in the Caribbean Sea, where it was sequenced from the water column, corals, and fish. Four distinct parasite lineages were found infecting farmed Dicentrarchus labrax or Sparus aurata. One of the lineages from farmed D. labrax was also found infecting wild counterparts, and another was also recovered from farmed S. aurata and farm-associated Diplodus sargus. Our results show that marine fish apicomplexans are diverse, and we highlight the need for a more extensive assessment of parasite diversity in this phylum. Additionally, parasites recovered from S. canicula were recovered as basal to their piscine counterparts reflecting hosts phylogeny.
CALYPTOSPORA FUNDULI (APICOMPLEXA): LIFE CYCLE AND TAXONOMY

EPA Science Inventory

The taxonomic status of the extraintestinal piscine coccidium Calyptospora funduli is based in part on its requirement of an intermediate host (the daggerblade grass shrimp, Palaemonetes pugio). Grass shrimp fed livers of Gulf killifish (Fundulus grandis) infected with sporulated...
LIFE CYCLE OF CALYPTOSPORA FUNDULI (APICOMPLEXA: CALYPTOSPORIDAE)

EPA Science Inventory

The taxonomic status of the extraintestinal piscine coccidium Calyptospora funduli is based in part on its requirement of an intermediate host (the daggerblade grass shrimp, Palaemonetes pugio). In this study, grass shrimp fed livers of Gulf killifish (Fundulus grandis) infected ...
Ultra-low input transcriptomics reveal the spore functional content and phylogenetic affiliations of poorly studied arbuscular mycorrhizal fungi

PubMed Central

Beaudet, Denis; Chen, Eric C H; Mathieu, Stephanie; Yildirir, Gokalp; Ndikumana, Steve; Dalpé, Yolande; Séguin, Sylvie; Farinelli, Laurent; Stajich, Jason E; Corradi, Nicolas

2018-01-01

Abstract Arbuscular mycorrhizal fungi (AMF) are a group of soil microorganisms that establish symbioses with the vast majority of land plants. To date, generation of AMF coding information has been limited to model genera that grow well axenically; Rhizoglomus and Gigaspora. Meanwhile, data on the functional gene repertoire of most AMF families is non-existent. Here, we provide primary large-scale transcriptome data from eight poorly studied AMF species (Acaulospora morrowiae, Diversispora versiforme, Scutellospora calospora, Racocetra castanea, Paraglomus brasilianum, Ambispora leptoticha, Claroideoglomus claroideum and Funneliformis mosseae) using ultra-low input ribonucleic acid (RNA)-seq approaches. Our analyses reveals that quiescent spores of many AMF species harbour a diverse functional diversity and solidify known evolutionary relationships within the group. Our findings demonstrate that RNA-seq data obtained from low-input RNA are reliable in comparison to conventional RNA-seq experiments. Thus, our methodology can potentially be used to deepen our understanding of fungal microbial function and phylogeny using minute amounts of RNA material. PMID:29211832
Habitat selection by owls in a seasonal semi-deciduous forest in southern Brazil.

PubMed

Menq, W; Anjos, L

2015-11-01

This paper tested the hypothesis that the structural components of vegetation have impact over the distribution of owl species in a fragment of a semi-deciduous seasonal forest. This paper also determined which vegetation variables contributed to the spatial distribution of owl species. It was developed in the Perobas Biological Reserve (PBR) between September and December 2011. To conduct the owl census, a playback technique was applied at hearing points distributed to cover different vegetation types in the study area. A total of 56 individual owls of six species were recorded: Tropical Screech-Owl (Megascops choliba), Black-capped Screech-Owl (Megascops atricapilla), Tawny-browed Owl (Pulsatrix koeniswaldiana), Ferruginous Pygmy-Owl (Glaucidium brasilianum), Mottled Owl (Strix virgata) and Stygian Owl (Asio stygius). The results suggest that the variables of vegetation structure have impact on the occurrence of owls. The canopy height, the presence of hollow trees, fallen trees and glades are the most important structural components influencing owl distribution in the sampled area.
Cryptosporidium avium n. sp. (Apicomplexa: Cryptosporidiidae) in birds

PubMed Central

Holubová, Nikola; Sak, Bohumil; Horčičková, Michaela; Hlásková, Lenka; Květoňová, Dana; Menchaca, Sarah; McEvoy, John; Kváč, Martin

2016-01-01

The morphological, biological, and molecular characteristics of Cryptosporidium avian genotype V are described, and the species name Cryptosporidium avium is proposed to reflect its specificity for birds under natural and experimental conditions. Oocysts of C. avium measured 5.30–6.90 μm (mean = 6.26 μm) × 4.30–5.50 μm (mean = 4.86 μm) with a length to width ratio of 1.29 (1.14–1.47). Oocysts of C. avium obtained from four naturally infected red-crowned parakeets (Cyanoramphus novaezealandiae) were infectious for 6-month-old budgerigars (Melopsittacus undulatus) and hens (Gallus gallus f. domestica). The prepatent periods in both susceptible bird species was 11 days post infection (DPI). The infection intensity of C. avium in budgerigars and hens was low, with a maximum intensity of 5,000 oocysts per gram of faeces. Oocysts of C. avium were microscopically detected at only 12–16 DPI in hens and 12 DPI in budgerigars, while PCR analyses revealed the presence of specific DNA in faecal samples from 11 to 30 DPI (the conclusion of the experiment). Cryptosporidium avium was not infectious for 8-week-old SCID and BALB/c mice (Mus musculus). Naturally or experimentally infected birds showed no clinical signs of cryptosporidiosis and no pathology was detected. Developmental stages of C. avium were detected in the ileum and caecum using scanning electron microscopy. Phylogenetic analyses based on small subunit rRNA, actin, and heat shock protein 70 gene sequences revealed that C. avium is genetically distinct from previously described Cryptosporidium species. PMID:26905074
Phylogeny of Fish-Infecting Calyptospora species (Apicomplexa: Eimeriorina)

EPA Science Inventory

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...
Cryptosporidium erinacei n. sp. (Apicomplexa: Cryptosporidiidae) in hedgehogs.

PubMed

Kváč, Martin; Hofmannová, Lada; Hlásková, Lenka; Květoňová, Dana; Vítovec, Jiří; McEvoy, John; Sak, Bohumil

2014-03-17

The morphological, biological, and molecular characteristics of Cryptosporidium hedgehog genotype are described, and the species name Cryptosporidium erinacei n. sp. is proposed to reflect its specificity for hedgehogs under natural and experimental conditions. Oocysts of C. erinacei are morphologically indistinguishable from Cryptosporidium parvum, measuring 4.5-5.8 μm (mean=4.9 μm) × 4.0-4.8 μm (mean=4.4 μm) with a length to width ratio of 1.13 (1.02-1.35) (n=100). Oocysts of C. erinacei obtained from a naturally infected European hedgehog (Erinaceus europaeus) were infectious for naïve 8-week-old four-toed hedgehogs (Atelerix albiventris); the prepatent period was 4-5 days post infection (DPI) and the patent period was longer than 20 days. C. erinacei was not infectious for 8-week-old SCID and BALB/c mice (Mus musculus), Mongolian gerbils (Meriones unguiculatus), or golden hamsters (Mesocricetus auratus). Phylogenetic analyses based on small subunit rRNA, 60 kDa glycoprotein, actin, Cryptosporidium oocyst wall protein, thrombospondin-related adhesive protein of Cryptosporidium-1, and heat shock protein 70 gene sequences revealed that C. erinacei is genetically distinct from previously described Cryptosporidium species. Copyright © 2014 Elsevier B.V. All rights reserved.
Ultra-low input transcriptomics reveal the spore functional content and phylogenetic affiliations of poorly studied arbuscular mycorrhizal fungi.

PubMed

Beaudet, Denis; Chen, Eric C H; Mathieu, Stephanie; Yildirir, Gokalp; Ndikumana, Steve; Dalpé, Yolande; Séguin, Sylvie; Farinelli, Laurent; Stajich, Jason E; Corradi, Nicolas

2017-12-02

Arbuscular mycorrhizal fungi (AMF) are a group of soil microorganisms that establish symbioses with the vast majority of land plants. To date, generation of AMF coding information has been limited to model genera that grow well axenically; Rhizoglomus and Gigaspora. Meanwhile, data on the functional gene repertoire of most AMF families is non-existent. Here, we provide primary large-scale transcriptome data from eight poorly studied AMF species (Acaulospora morrowiae, Diversispora versiforme, Scutellospora calospora, Racocetra castanea, Paraglomus brasilianum, Ambispora leptoticha, Claroideoglomus claroideum and Funneliformis mosseae) using ultra-low input ribonucleic acid (RNA)-seq approaches. Our analyses reveals that quiescent spores of many AMF species harbour a diverse functional diversity and solidify known evolutionary relationships within the group. Our findings demonstrate that RNA-seq data obtained from low-input RNA are reliable in comparison to conventional RNA-seq experiments. Thus, our methodology can potentially be used to deepen our understanding of fungal microbial function and phylogeny using minute amounts of RNA material. © The Author 2017. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.
Life cycle of Hammondia hammondi (Apicomplexa: Sarcocystidae) in cats

USDA-ARS?s Scientific Manuscript database

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...

Malaria in Farmed Ungulates: an Exciting New System for Comparative Parasitology.

PubMed

Perkins, Susan L

2018-04-25

A wide array of vertebrates can serve as the intermediate hosts to malaria parasites (Apicomplexa: Haemosporida), such as birds, lizards, and several groups of mammals, including primates, bats, rodents, and ungulates. The latter group of hosts has not been intensively studied since early descriptions of a small set of taxa were published, but new reports of these parasites in both expected and new hosts have recently been published. A new paper reports the presence of Plasmodium odocoilei in farmed white-tailed deer in Florida, particularly in animals less than 1 year old, and provides evidence that the parasites may contribute to mortality in fawns. That paper opens new opportunities to study the malaria parasite-mammal interface in North America. Copyright © 2018 Perkins.
Sirtuins of parasitic protozoa: In search of function(s)

PubMed Central

Religa, Agnieszka A.; Waters, Andrew P.

2012-01-01

The SIR2 family of NAD+-dependent protein deacetylases, collectively called sirtuins, has been of central interest due to their proposed roles in life-span regulation and ageing. Sirtuins are one group of environment sensors of a cell interpreting external information and orchestrating internal responses at the sub-cellular level, through participation in gene regulation mechanisms. Remarkably conserved across all kingdoms of life SIR2 proteins in several protozoan parasites appear to have both conserved and intriguing unique functions. This review summarises our current knowledge of the members of the sirtuin families in Apicomplexa, including Plasmodium, and other protozoan parasites such as Trypanosoma and Leishmania. The wide diversity of processes regulated by SIR2 proteins makes them targets worthy of exploitation in anti-parasitic therapies. PMID:22906508
Multiple host-switching of Haemosporidia parasites in bats

PubMed Central

Duval, Linda; Robert, Vincent; Csorba, Gabor; Hassanin, Alexandre; Randrianarivelojosia, Milijaona; Walston, Joe; Nhim, Thy; Goodman, Steve M; Ariey, Frédéric

2007-01-01

Background There have been reported cases of host-switching in avian and lizard species of Plasmodium (Apicomplexa, Haemosporidia), as well as in those infecting different primate species. However, no evidence has previously been found for host-swapping between wild birds and mammals. Methods This paper presents the results of the sampling of blood parasites of wild-captured bats from Madagascar and Cambodia. The presence of Haemosporidia infection in these animals is confirmed and cytochrome b gene sequences were used to construct a phylogenetic analysis. Results Results reveal at least three different and independent Haemosporidia evolutionary histories in three different bat lineages from Madagascar and Cambodia. Conclusion Phylogenetic analysis strongly suggests multiple host-switching of Haemosporidia parasites in bats with those from avian and primate hosts. PMID:18045505
Natural infection of Cryptosporidium muris (Apicomplexa: Cryptosporiidae) in Siberian chipmunks.

PubMed

Hůrková, Lada; Hajdusek, Ondrej; Modrý, David

2003-04-01

Coprologic examination of nine Siberian chipmunks (Eutamias sibiricus) imported from Southeast Asia revealed infection with Cryptosporidium sp. Experimental inoculation of BALB/c mice proved their susceptibility to the infection. Infected mice shed oocysts 14-35 days postinfection. Oocyst morphology was similar to that reported for C. muris in previous studies, oocysts were 8.1 (7.0-9.0) x 5.9 (5.0-6.5) microns. Clinical signs were absent in naturally infected chipmunks and experimental mice. Histologic examinations of mice revealed numerous developmental stages of C. muris in the glandular stomach. Analysis of partial small subunit rRNA gene sequences confirmed identity of these isolates as C. muris. Our results represent the first report of C. muris in members of the family Sciuridae.
The complete mitochondrial genome sequence of Eimeria magna (Apicomplexa: Coccidia).

PubMed

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.
Analysis of the Sarcocystis neurona microneme protein SnMIC10: protein characteristics and expression during intracellular development.

PubMed

Hoane, Jessica S; Carruthers, Vernon B; Striepen, Boris; Morrison, David P; Entzeroth, Rolf; Howe, Daniel K

2003-07-01

Sarcocystis neurona, an apicomplexan parasite, is the primary causative agent of equine protozoal myeloencephalitis. Like other members of the Apicomplexa, S. neurona zoites possess secretory organelles that contain proteins necessary for host cell invasion and intracellular survival. From a collection of S. neurona expressed sequence tags, we identified a sequence encoding a putative microneme protein based on similarity to Toxoplasma gondii MIC10 (TgMIC10). Pairwise sequence alignments of SnMIC10 to TgMIC10 and NcMIC10 from Neospora caninum revealed approximately 33% identity to both orthologues. The open reading frame of the S. neurona gene encodes a 255 amino acid protein with a predicted 39-residue signal peptide. Like TgMIC10 and NcMIC10, SnMIC10 is predicted to be hydrophilic, highly alpha-helical in structure, and devoid of identifiable adhesive domains. Antibodies raised against recombinant SnMIC10 recognised a protein band with an apparent molecular weight of 24 kDa in Western blots of S. neurona merozoites, consistent with the size predicted for SnMIC10. In vitro secretion assays demonstrated that this protein is secreted by extracellular merozoites in a temperature-dependent manner. Indirect immunofluorescence analysis of SnMIC10 showed a polar labelling pattern, which is consistent with the apical position of the micronemes, and immunoelectron microscopy provided definitive localisation of the protein to these secretory organelles. Further analysis of SnMIC10 in intracellular parasites revealed that expression of this protein is temporally regulated during endopolygeny, supporting the view that micronemes are only needed during host cell invasion. Collectively, the data indicate that SnMIC10 is a microneme protein that is part of the excreted/secreted antigen fraction of S. neurona. Identification and characterisation of additional S. neurona microneme antigens and comparisons to orthologues in other Apicomplexa could provide further insight into the
Electron microscopic study on macrogametogenesis of Eimeria labbeana infecting the Egyptian wild doves and host-parasite relationship.

PubMed

Bashtar, A R; Abdel-Ghaffar, F A; Ahmed, A K

1991-04-01

The development of macrogametes of Eimeria labbeana was studied by electron microscopy in the epithelial cells of the villi at 96 hrs. post-infection. Appearance of young macrogamonts was characterized by the loss of the architecture of the apicomplexa (polar ring, rhoptries, micronemes, conoid, subpellicular microtubules), while the pellicle became only one unit membrane. This was associated by the formation of wall forming bodies II then I. Moreover, the mitochondria, endoplasmic reticulum and Golgi were increased in the cytoplasm. Amylopectin granules as well as lipid globules were greatly increased in mature macrogametes. Host cell reaction due to infection included enlargement and deformation of infected cells, hypertrophy of their nuclei, swollen and degeneration of mitochondria, endoplasmic reticulum and vacuolation of ground cytoplasm. These changes occur in both cells with and without parasite.
Toxoplasma gondii infection in humans in China

PubMed Central

2011-01-01

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. PMID:21864327
ApiEST-DB: analyzing clustered EST data of the apicomplexan parasites.

PubMed

Li, Li; Crabtree, Jonathan; Fischer, Steve; Pinney, Deborah; Stoeckert, Christian J; Sibley, L David; Roos, David S

2004-01-01

ApiEST-DB (http://www.cbil.upenn.edu/paradbs-servlet/) provides integrated access to publicly available EST data from protozoan parasites in the phylum Apicomplexa. The database currently incorporates a total of nearly 100,000 ESTs from several parasite species of clinical and/or veterinary interest, including Eimeria tenella, Neospora caninum, Plasmodium falciparum, Sarcocystis neurona and Toxoplasma gondii. To facilitate analysis of these data, EST sequences were clustered and assembled to form consensus sequences for each organism, and these assemblies were then subjected to automated annotation via similarity searches against protein and domain databases. The underlying relational database infrastructure, Genomics Unified Schema (GUS), enables complex biologically based queries, facilitating validation of gene models, identification of alternative splicing, detection of single nucleotide polymorphisms, identification of stage-specific genes and recognition of phylogenetically conserved and phylogenetically restricted sequences.
Molecular characterisation of Cryptosporidium (Apicomplexa) in children and cattle in Romania.

PubMed

Vieira, Patricia Manuela; Mederle, Narcisa; Lobo, Maria Luisa; Imre, Kalman; Mederle, Ovidiu; Xiao, Lihua; Darabus, Gheorghe; Matos, Olga

2015-01-01

To investigate the transmission of species of Cryptosporidium Tyzzer, 1907 in Timis County, Romania, 48 isolates of Cryptosporidium coccidia from 11 children, 29 calves and eight pigs were characterised by molecular analysis of two loci (SSU rRNA and 60-kDa glycoprotein gene). Overall, 22 isolates were amplified and sequence analyses revealed that all isolates were Cryptosporidium parvum Tyzzer, 1912. Two subtype families were identified, IIa and IId. Subtype IIdA22G1 (n = 4) was the single C. parvum subtype found in children. Subtypes found in calves included IIdA27G1 (n = 8), a novel subtype, IIdA25G1 (n = 5), IIdA22G1 (n = 2), IIdA21G1a (n = 1), and IIaA16G1R1 (n = 1). Subtype IIdA26G1 was found in a pig. These results were significantly different from previous Romanian reports, as the five subtypes of family IId identified in this study were never identified previously in this country. Thus, cattle may be a source of Cryptosporidium infections for humans and the transmission dynamics of C. parvum in Romania is more complex than previously believed.
Goussia girellae n. sp. (Apicomplexa: Eimeriorina) in the opaleye, Girella nigricans.

PubMed

Kent, M L; Fournie, J W; Snodgrass, R E; Elston, R A

1988-05-01

Goussia girellae n. sp. is described from the opaleye fish, Girella nigricans. Merogonic stages were observed in the apices of intestinal epithelial cells, in the lamina propria, and in extra-intestinal sites including liver, gills, and spleen. Gamonts were observed in the intestinal epithelial cells. Only unsporulated oocysts were detected in the intestine, and sporulation occurred when feces containing oocysts were incubated for 48 h in seawater at 21 degrees C. Oocysts are elongated (24.8 x 14.7 micron) with a wall about 200 nm thick and have no residuum, micropyle, or polar granule. Sporocysts are ellipsoid (8.5 x 4.5 micron), have a thin two-layered wall approximately 30 nm thick, and consist of two valves joined by a suture. Although moribund opaleye were also infected with Gyrodactylus sp., Cryptobia sp., Cardicola sp., and epitheliocystis organisms (chlamydia), all fish were heavily infected with G. girellae and morbidity was thus attributed to the coccidium.
[Newly established causes of diarrhea: the protozoan Cyclospora cayetanensis (Coccidia, Apicomplexa)].

PubMed

Lepes, T

1998-01-01

Coccidia Cyclospora cavetanesis has been considered a saprophytic or accidental infection without special medical significance until 1984. However, epidemics of diarrhea first in Peru and later in USA. Haiti and Nepal have aroused interest in pathogenic characteristics of this parasite and diseases it causes. The study first deals with biological cycle of parasite development as well as clinical picture and treatment, diagnostics and epidemiology of this parasitic disease. On average the incubation period was 2-11 days with frequent stools (3 or more times a day) without blood or mucus and with tendency for recurrence. The prodromal phase is similar to influenza. It may last several weeks especially in immunodeficient persons (especially patients with AIDS). Trimethoprim (160 mg) and sulfamethoxazole (800 mg) is the treatment of choice, twice a day during a 7 day period, whereas in immunodeficient patients greater doses are necessary during a few weeks, but in such cases individual treatment planning is required. Laboratory diagnosis is made on the basis of microscopic examination of native preparation from the stool, especially if stool concentration procedure is used due to small number of oocysts in the stool. As this method does not provide identification of species, numerous staining methods are recommended (modified Ziehl-Neelsen method, Carbol-Fuchsin and safranine). Epidemiology is still unclear. It is considered that there are two sources of infection: contaminated drinking water and fruits. The disease has a seasonal character and the highest incidence is recorded in late spring and summer months. The infection is caused only by sporozoites developed by sporulation of oocysts under environmental conditions excluding the possibility of direct transmission from one person to another. It is to be expected that further investigations will give answers to numerous questions still open.
CRYPTOSPORIDIUM HOMINIS N. SP (APICOMPLEXA : CRYPTOSPORIDIIDAE) FROM HOMO SAPIENS. (R826138)

EPA Science Inventory

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

USDA-ARS?s Scientific Manuscript database

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...
Hepatozoon infection prevalence in four snake genera: influence of diet, prey parasitemia levels, or parasite type?

PubMed

Tomé, Beatriz; Maia, João P M C; Harris, D James

2012-10-01

Hepatozoon spp. (Apicomplexa: Haemogregarinidae) are the most commonly reported hemoparasites from snakes. Of over 300 Hepatozoon species identified, more than 120 were described from snakes. However, recent genetic assessments have found Hepatozoon lineages recovered from both prey and predators, indicating that diet may play an important role in the infection of final vertebrate hosts. Here 4 different snake genera with different diets were assessed. Hepatozoon spp. prevalence varied greatly between the genera, but only lineages already identified from potential prey, i.e., gecko and lacertid lizards, were recovered from the snakes. Interestingly, the Hepatozoon spp. lineage known from geckos was the most common in the snakes, but this does not reflect their diet. Higher parasitemia levels, reported for some geckos relative to lacertid lizards, may play a role. Alternatively, this lineage may be more effective at parasitizing snakes or may occur, despite being unrecorded, in other vertebrate groups consumed by snakes.
Molecular cloning and characterization of an SRCAP chromatin remodeling homologue in Toxoplasma gondii.

PubMed

Sullivan, William J; Monroy, M Alexandra; Bohne, Wolfgang; Nallani, Karuna C; Chrivia, John; Yaciuk, Peter; Smith, Charles K; Queener, Sherry F

2003-05-01

We have identified and mapped a gene in Toxoplasma gondii that encodes a homologue of SRCAP (Snf2-related CBP activator protein), a member of the SNF/SWI family of chromatin remodeling factors. The genomic locus (TgSRCAP) is present as a single copy and contains 16 introns. The predicted cDNA contains an open reading frame of 8,775 bp and encodes a protein of 2,924 amino acids. We have identified additional SRCAP-like sequences in Apicomplexa for comparison by screening genomic databases. An analysis of SRCAP homologues between species reveals signature features that may be indicative of SRCAP members. Expression of mRNA encoding TgSRCAP is upregulated when tachyzoite (invasive form) parasites are induced to differentiate into bradyzoites (encysted form) in vitro. Recombinant TgSRCAP protein is functionally equivalent to the human homologue, being capable of increasing transcription mediated by CREB.
Synergic in vitro combinations of artemisinin, pyrimethamine and methylene blue against Neospora caninum.

PubMed

Pereira, Luiz Miguel; de Luca, Gabriela; Abichabki, Nathália de Lima Martins; Bronzon da Costa, Cássia Mariana; Yatsuda, Ana Patrícia

2018-01-15

Neospora caninum is a member of Apicomplexa phylum, the causative agent of neosporosis. The neosporosis combat is not well established and several strategies related to vaccine, chemotherapy and immune modulation are under development. In this work, we evaluated the effects of artemisinin (Art), methylene blue (MB) and pyrimethamine (Pyr) alone or associated, on N. caninum proliferation and elimination using LacZ tagged tachyzoites. The reactive oxygen species (ROS) production after incubation with Art were also performed. Our results indicate that combinations of classical antimalarial drugs improve the parasite control, allowing the use of three drugs in a single dose. Additionally, artemisinin demonstrated distinct ROS production patterns in intra and extracellular N. caninum forms. The drug repurposing appears as a suitable approach, allowing a fast and safe method to evaluate old drugs but novel candidates against neosporosis. Copyright © 2017 Elsevier B.V. All rights reserved.
A seroprevalence and descriptive epidemiological study of malaria among Indian tribes of the Amazon basin of Brazil.

PubMed

de Arruda, M E; Aragaki, C; Gagliardi, F; Haile, R W

1996-04-01

Data on the seroprevalences of Plasmodium falciparum, P. vivax, and P. malariae in four isolated Indian tribes of the Amazon basin in Brazil, as determined by IFAT, were re-analysed. Age-, sex- and tribe-specific geometric mean antibody titres and externally standardized prevalence ratios were calculated for each parasite species. Correlation coefficients and prevalence odds ratios were also calculated for multiple infections with different combinations of the three Plasmodium species. Titres of all but one of the antibodies studied were similar in males and females; titres of antibodies to the blood stages of P. malariae were slightly higher in females than in males. Titres of antibodies to all three Plasmodium species increased with subject age, and this age effect was not confounded by sex or tribal differences. There were striking differences between tribes, with the Parakana tribe having relatively low titres of antibodies against P. falciparum and P. malariae; these tribal effects were not confounded by sex or age differences between tribes. The results indicate that conditions conductive to the transmission of P. malariae exist in this region of the Amazon. The potential for zoonotic transmission of P. brasilianum, a parasite of monkeys which is morphologically similar to P. malarie, and the generally high rates of seropositivity to all three species of Plasmodium indicate that control measures which are adequate and applicable to the region studied need to be developed.
Four additional hepatozoon species (Apicomplexa: Hepatozoidae) from north Florida ratsnakes, genus Pantherophis.

PubMed

Telford, Sam R; Moler, Paul E; Butler, Jerry F

2012-09-01

Records from a colubrid host are reported for Hepatozoon horridus, described originally from a viperid snake. Hepatozoon horridus in Pantherophis guttatus (Colubridae) has gamonts 14-18.0 by 4.0-5.5 microm, with length by width (LW) 60-99 microm2, and L/W ratio 2.5-3.9. Spherical to elongate, usually ovoid oocysts with L/W ratio 1.0-3.7 contain 16-160 spherical to usually ovoid sporocysts 15-31 by 14-26 microm, with L/W ratio 1.0-1.4, that contain 5-24 sporozoites. Two additional Hepatozoon species are described from ratsnakes in north Florida. Hepatozoon quadrivittata n. sp. from Pantherophis obsoletus quadrivittatus has gamonts 12-17 by 4-6 microm, LW 56-102 microm2, and L/W ratio 2.6-3.8. Nearly spherical oocysts with L/W 1.0-1.1 contain 5-227 spherical to slightly ovoid sporocysts 20-48 by 19-45 microm, with L/W ratio 1.0-1.4, that contain 13-48 sporozoites. Hepatozoon spiloides n. sp. from Pantherophis obsoletus spiloides forms gamonts 12-15 by 4-5 microm with LW 48-75 microm2 and L/W ratio 2.6-3.5. Occasionally rounded but usually elongate oocysts, with L/W ratio 1.0-2.7, contain 5-21 spherical to elongate sporocysts 28-43 by 18-35 microm, L/W ratio 2.5-3.9. In the distinctive Hepatozoon sp. present in Pantherophis obsoletus spiloides, gamonts are 13-17 by 5-10 microm, with LW 75-140 microm2 and L/W ratio 1.4-3.0. Infected erythrocytes are always distorted and enlarged on average 2.5 times the size of uninfected cells, with nuclei enlarged by one-third and broadly elongated. Gamonts often stained deep blue, and cytoplasm of erythrocytes infected with mature gamonts was always dehemoglobinized. Sporogony could not be obtained in three feedings by hundreds of Aedes aegypti, which usually died within the first 24-48 hr.
Sarcocystis cafferi, n. sp. (Protozoa: Apicomplexa) from the African buffalo (Syncerus caffer)

USDA-ARS?s Scientific Manuscript database

Four species of Sarcocystis are currently recognized in the Asian water buffalo (Bubalus bubalis): Sarcocystis fusiformis with macrocysts and cats as definitive hosts, S. buffalonis also with macrocysts and cats as definitive hosts, S. levinei with microcysts and dogs as definitive hosts, and S. dub...

CRYPTOSPORIDIUM ANDERSONI N. SP. (APICOMPLEXA: CRYPTOSPORIDIIDAE) FROM CATTLE, BOS TAURUS. (R825148)

EPA Science Inventory

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...
Pampas fox (Lycalopex gymnocercus) new intermediate host of Sarcocystis svanai (Apicomplexa: Sarcocystidae).

PubMed

Scioscia, Nathalia P; Olmos, Leandro; Gorosábel, Antonella; Bernad, Lucía; Pedrana, Julieta; Hecker, Yanina P; Gual, Ignacio; Laura Gos, M; Denegri, Guillermo M; Moore, Dadín P; Moré, Gastón

2017-06-01

Several Sarcocystis spp. have carnivores as definitive host and sarcocysts are common in muscles of herbivores (intermediate host). However, sarcocysts have been found in muscles of wild and domestic carnivores suggesting they are intermediate host for some Sarcocystis spp. Here, we report mature sarcocysts in the muscles of Pampas fox (Lycalopex gymnocercus). A total of 36 free-living foxes were analyzed. Different skeletal muscles were assessed by microscopic and molecular methods. Cysts and/or DNA of Sarcocystis sp. were detected in 61.1% (22/36) foxes. Histopathology revealed the presence of sarcocysts in 52.8% (19/36) foxes. The tongue and masseter were the muscles more frequently infected. Of all the samples processed by homogenization of pooled muscles of each animal, 45.4% (10/22) evidenced muscle cysts and 68.2% (15/22) resulted positives by PCR. Individual cysts obtained from the ten positive samples in direct microscopic examination were all positive by PCR. Five amplicons from individual cysts from different samples were selected for sequencing together with four PCR products obtained from the pooled muscles. All nine sequences shared a high identity among them (99.8-100%) and showed the highest identity by BLAST (99%) with a S. svanai sequence (KM362428) from a North American dog. By transmission electron microscopy, the sarcocyst wall was thin (<1μm), had minute undulations, with tiny evaginations and without evident villar protrusions. The cyst wall type is referred as "type 1". Sarcocystis svanai infects L. gymnocercus with a high prevalence and the presence of mature sarcocysts suggests the role of the Pampas fox as natural intermediate host. The definitive host of S. svanai remains unknown. Copyright © 2017 Elsevier B.V. All rights reserved.
Experimental Infection with Sporulated Oocysts of Eimeria maxima (Apicomplexa: Eimeriidae) in Broiler

PubMed Central

Brito, Luciana da S.; Pereira, Elder N.; da Silva, Augusta A.; Bentivóglio Costa Silva, Vinícius; Freitas, Fagner L. da C.

2014-01-01

Through this study we assessed the metabolic and pathological changes in broilers experimentally infected with oocysts of Eimeria maxima. To perform the experiment, we used 150 broiler strain cooB males, with ten days of age, were randomized according to weight and randomly assigned to two experimental groups: the control group was inoculated with 0.5 mL of distilled water; the infected group inoculated with 0.5 mL of solution containing 5 × 104 sporulated oocysts of Eimeria maxima. The live performance was evaluated on day 0 (day of inoculation), 5°, 10°, 15°, 25°, and 35° dpi, being slaughtered by cervical dislocation, fifteen birds/group. Although the sum in meat production was higher in the control group, the weight of the heart and gizzard of the experimental animals showed no significant difference, while the liver had difference on day 5°, 15°, and 35° dpi. The pathologic evaluation showed congested mucosa and presence of large amounts of mucus at 6 dpi. Therefore, it is concluded that the dose of 5 × 104 E. maxima inoculated in the experimental group was enough to cause harm to the animal organism. PMID:26464925
[Achatina fulica Bowdich (1822) a new host of Cryptosporidium (Apicomplexa, Cryptosporidiidae) species].

PubMed

Schiffler, Cinthia L; Gomes, Francimar F; Ederli, Nicole B; De Oliveira, Francisco Carlos R

2008-09-01

With the objective of isolate Cryptosporidium spp. in Achatina fulica s feces, 50 mollusks were collected in nine neighborhoods of the municipal of Campos dos Goytacazes, RJ to the observation of oocysts in feces. The snails were put in individuals containers and fed with water and green vegetables ad libitum until be collected a gram of feces per animal. The samples were conditioned in tubes with formalin 10% and later smear of feces were made and dyed by Ziechl-Neelsen modified technique. Of the 50 samples examined, 26 (52%) were positive for the presence of oocysts of Cryptosporidium spp. The morphology and morphometry of the oocysts showed that are a great morphologic variability. Considering the obtained results, the mollusk Achatina fulica is a host of Cryptosporidium species and can participate in the epidemic chain of the cryptosporidiosis.
Cryptosporidium homai n. sp. (Apicomplexa: Cryptosporidiiae) from the guinea pig (Cavia porcellus).

PubMed

Zahedi, Alireza; Durmic, Zoey; Gofton, Alexander W; Kueh, Susan; Austen, Jill; Lawson, Malcolm; Callahan, Lauren; Jardine, John; Ryan, Una

2017-10-15

The morphological, biological, and molecular characterisation of a new Cryptosporidium species from the guinea pig (Cavia porcellus) are described, and the species name Cryptosporidium homai n. sp. is proposed. Histological analysis conducted on a post-mortem sample from a guinea pig euthanised due to respiratory distress, identified developmental stages of C. homai n. sp. (trophozoites and meronts) along the intestinal epithelium. Molecular analysis at 18S rRNA (18S), actin and hsp70 loci was then conducted on faeces from an additional 7 guinea pigs positive for C. homai n. sp. At the 18S, actin and hsp70 loci, C. homai n. sp. exhibited genetic distances ranging from 3.1% to 14.3%, 14.4% to 24.5%, and 6.6% to 20.9% from other Cryptosporidium spp., respectively. At the 18S locus, C. homai n. sp. shared 99.1% similarity with a previously described Cryptosporidium genotype in guinea pigs from Brazil and it is likely that they are the same species, however this cannot be confirmed as actin and hsp70 sequences from the Brazilian guinea pig genotype are not available. Phylogenetic analysis of concatenated 18S, actin and hsp70 sequences showed that C. homai n. sp. exhibited 9.1% to 17.3% genetic distance from all other Cryptosporidium spp. This clearly supports the validity of C. homai n. sp. as a separate species. Copyright © 2017 Elsevier B.V. All rights reserved.
Prevalence of Eimeria (Apicomplexa: Eimeriidae) in reintroduced Gunnison's prairie dogs (Cynomys gunnisoni)

Treesearch

M. M. Ryan; K. H. Decker; D. W. Duszynski

2001-01-01

Fecal samples from 54 Gunnison's prairie dogs (Cynomys gunnisoni) from Albuquerque, NM were analyzed for the presence of coccidia and all were positive. They were then relocated to an abandoned prairiedog town on the Sevilleta Long Term Ecological Research (LTER) site. Six Eimeria species, E. callospermophili, E. cynomysis, E. pseudospermophili (new host record),...
Molecular identification of Sarcocystis lutrae in the European otter (Lutra lutra) and the European badger (Meles meles) from the Czech Republic.

PubMed

Máca, Ondřej

2018-03-01

Muscular sarcosporidial infections by Sarcocystis lutrae (Apicomplexa: Sarcocystidae) from the otter (Lutra lutra) and badger (Meles meles) (Carnivora: Mustelidae) were found in the Czech Republic. As part of a diversity evaluation of Sarcocystis in wild carnivores during 2016-2017, samples of diaphragm, tongue and hind-limb muscles were collected from nine districts, examined by compression and characterized molecularly. Cyst walls were thin, with no visible protrusions, and histological sections of infected muscle tissue showed no host responses. Fourteen of 17 badgers (82% prevalence) and one otter (100% prevalence) were positive for sarcocysts. Sequence analyses at four loci (18S rRNA, 28S rRNA, ITS1 and cox1) confirmed the identity as S. lutrae. This is also the first report of a co-infection with muscular sarcocystosis and Trichinella in badger. The finding of Trichinella is important from the zoonotic point of view, since badgers are used for meat consumption. Similar and future monitoring of both parasitic taxa are needed.
Everybody needs sphingolipids, right! Mining for new drug targets in protozoan sphingolipid biosynthesis.

PubMed

Mina, John G M; Denny, P W

2018-02-01

Sphingolipids (SLs) are an integral part of all eukaryotic cellular membranes. In addition, they have indispensable functions as signalling molecules controlling a myriad of cellular events. Disruption of either the de novo synthesis or the degradation pathways has been shown to have detrimental effects. The earlier identification of selective inhibitors of fungal SL biosynthesis promised potent broad-spectrum anti-fungal agents, which later encouraged testing some of those agents against protozoan parasites. In this review we focus on the key enzymes of the SL de novo biosynthetic pathway in protozoan parasites of the Apicomplexa and Kinetoplastidae, outlining the divergence and interconnection between host and pathogen metabolism. The druggability of the SL biosynthesis is considered, alongside recent technology advances that will enable the dissection and analyses of this pathway in the parasitic protozoa. The future impact of these advances for the development of new therapeutics for both globally threatening and neglected infectious diseases is potentially profound.
Phosphatidic Acid-Mediated Signaling Regulates Microneme Secretion in Toxoplasma.

PubMed

Bullen, Hayley E; Jia, Yonggen; Yamaryo-Botté, Yoshiki; Bisio, Hugo; Zhang, Ou; Jemelin, Natacha Klages; Marq, Jean-Baptiste; Carruthers, Vern; Botté, Cyrille Y; Soldati-Favre, Dominique

2016-03-09

The obligate intracellular lifestyle of apicomplexan parasites necessitates an invasive phase underpinned by timely and spatially controlled secretion of apical organelles termed micronemes. In Toxoplasma gondii, extracellular potassium levels and other stimuli trigger a signaling cascade culminating in phosphoinositide-phospholipase C (PLC) activation, which generates the second messengers diacylglycerol (DAG) and IP3 and ultimately results in microneme secretion. Here we show that a delicate balance between DAG and its downstream product, phosphatidic acid (PA), is essential for controlling microneme release. Governing this balance is the apicomplexan-specific DAG-kinase-1, which interconverts PA and DAG, and whose depletion impairs egress and causes parasite death. Additionally, we identify an acylated pleckstrin-homology (PH) domain-containing protein (APH) on the microneme surface that senses PA during microneme secretion and is necessary for microneme exocytosis. As APH is conserved in Apicomplexa, these findings highlight a potentially widely used mechanism in which key lipid mediators regulate microneme exocytosis. Copyright © 2016 Elsevier Inc. All rights reserved.
An Apicomplexan Actin-Binding Protein Serves as a Connector and Lipid Sensor to Coordinate Motility and Invasion.

PubMed

Jacot, Damien; Tosetti, Nicolò; Pires, Isa; Stock, Jessica; Graindorge, Arnault; Hung, Yu-Fu; Han, Huijong; Tewari, Rita; Kursula, Inari; Soldati-Favre, Dominique

2016-12-14

Apicomplexa exhibit a unique form of substrate-dependent gliding motility central for host cell invasion and parasite dissemination. Gliding is powered by rearward translocation of apically secreted transmembrane adhesins via their interaction with the parasite actomyosin system. We report a conserved armadillo and pleckstrin homology (PH) domain-containing protein, termed glideosome-associated connector (GAC), that mediates apicomplexan gliding motility, invasion, and egress by connecting the micronemal adhesins with the actomyosin system. TgGAC binds to and stabilizes filamentous actin and specifically associates with the transmembrane adhesin TgMIC2. GAC localizes to the apical pole in invasive stages of Toxoplasma gondii and Plasmodium berghei, and apical positioning of TgGAC depends on an apical lysine methyltransferase, TgAKMT. GAC PH domain also binds to phosphatidic acid, a lipid mediator associated with microneme exocytosis. Collectively, these findings indicate a central role for GAC in spatially and temporally coordinating gliding motility and invasion. Copyright © 2016 Elsevier Inc. All rights reserved.
Detection of Theileria luwenshuni in sheep from Great Britain.

PubMed

Phipps, L Paul; Hernández-Triana, Luis M; Goharriz, Hooman; Welchman, David; Johnson, Nicholas

2016-04-13

Theileria spp. are tick-borne protozoan parasites of the Phylum Apicomplexa, Order Piroplasmida that infect a wide range of wild and domestic animals. In Great Britain, Theileria spp. have been reported from livestock associated with transmission by the tick Haemaphysalis punctata. However, these reports have not been associated with disease. This study has investigated the cause of a disease outbreak accompanied by mortality in a flock of sheep grazing reclaimed marshland in north Kent. A polymerase chain reaction-reverse line blot assay indicated the presence of Theileria spp. in blood samples from five animals. Subsequent testing with a pan-piroplasm PCR of a larger panel of blood samples detected a piroplasm amplicon in 19 of 21 sheep submitted from the affected flock. Automated sequencing confirmed that these amplicons shared 99-100% identity with T. luwenshuni. The clinical and PCR data suggest infection with T. luwenshuni was associated with disease and mortality in this flock.
Towards a molecular understanding of the apicomplexan actin motor: on a road to novel targets for malaria remedies?

PubMed

Kumpula, Esa Pekka; Kursula, Inari

2015-05-01

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.
Malaria immunity in man and mosquito: insights into unsolved mysteries of a deadly infectious disease

PubMed Central

Crompton, Peter D.; Moebius, Jacqueline; Portugal, Silvia; Waisberg, Michael; Hart, Geoffrey; Garver, Lindsey S.; Miller, Louis H.; Barillas, Carolina; Pierce, Susan K.

2014-01-01

Malaria is a mosquito-borne disease caused by parasites of the obligate intracellular Apicomplexa family, the most deadly of which, Plasmodium falciparum, prevails in Africa. Malaria imposes a huge health burden on the world’s most vulnerable populations, claiming the lives of nearly a million children and pregnant women each year in Africa alone. Although there is keen interest in eradicating malaria, we do not yet have the necessary tools to meet this challenge, including an effective malaria vaccine and adequate vector control strategies. Here we review what is known about the mechanisms at play in immune resistance to malaria in both the human and mosquito hosts at each step in the parasite’s complex life cycle with a view towards developing the tools that will contribute to the prevention of disease and death and ultimately the goal of malaria eradication. In so doing we hope to inspire immunologists to participate in defeating this devastating disease. PMID:24655294
Chromerid genomes reveal the evolutionary path from photosynthetic algae to obligate intracellular parasites.

PubMed

Woo, Yong H; Ansari, Hifzur; Otto, Thomas D; Klinger, Christen M; Kolisko, Martin; Michálek, Jan; Saxena, Alka; Shanmugam, Dhanasekaran; Tayyrov, Annageldi; Veluchamy, Alaguraj; Ali, Shahjahan; Bernal, Axel; del Campo, Javier; Cihlář, Jaromír; Flegontov, Pavel; Gornik, Sebastian G; Hajdušková, Eva; Horák, Aleš; Janouškovec, Jan; Katris, Nicholas J; Mast, Fred D; Miranda-Saavedra, Diego; Mourier, Tobias; Naeem, Raeece; Nair, Mridul; Panigrahi, Aswini K; Rawlings, Neil D; Padron-Regalado, Eriko; Ramaprasad, Abhinay; Samad, Nadira; Tomčala, Aleš; Wilkes, Jon; Neafsey, Daniel E; Doerig, Christian; Bowler, Chris; Keeling, Patrick J; Roos, David S; Dacks, Joel B; Templeton, Thomas J; Waller, Ross F; Lukeš, Julius; Oborník, Miroslav; Pain, Arnab

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.
[The taxonomic rank and place of Colpodellida in the system of the Protista].

PubMed

Myl'nikov, A P; Krylov, M V; Frolov, A O

2000-01-01

The analysis of ultrastructure organisation and divergent processes in Colpodellida, Perkinsida, Gregarinea and Coccidea has confirmed the presence of unique basic structures in all of these organisms and the necessity to combine them into the single phylum Sporozoa. A taxonomic rank and place of Colpodellida in the system of living organisms is represented as follows: phylum Sporozoa Leuckart, 1879; em. Krylov, Mylnikov, 1986. (Syn.: Apicomplexa Levine, 1970). Predators or parasites. Common basic structure: pellicular membranes, subpellicular microtubules, micropores, conoid, rhoptries and micronemes, tubular mitochondrial cristae. Class Perkinsea Levine, 1978. Predators or parasites, vegetative stages with two heterodynamic flagella. Subclass 1. Colpodellia nom. nov. (Syn.: Spiromonadia Krylov, Mylnikov, 1986). Predators, two heterodynamic flagella with string-like mastigonemes (if present), division is exclusively within a cyst, with 2-4 daughter cells being produced, extrusomes are trichocyst-like. Subclass 2. Perkinsia Levine, 1978. Parasites, zoospores with two heterodynamic flagella, mastigonemes (if present) bristle-like or string-like.
Previously unknown apicomplexan species infecting Iceland scallop, Chlamys islandica (Müller, 1776), queen scallop, Aequipecten opercularis L., and king scallop, Pecten maximus L.

PubMed

Kristmundsson, Árni; Helgason, Sigurður; Bambir, Slavko Helgi; Eydal, Matthías; Freeman, Mark A

2011-11-01

Examination of three scallop species from three separate locations: Iceland scallop from Icelandic waters, king scallop from Scottish waters and queen scallop from Faroese and Scottish waters, revealed infections of a previously unknown apicomplexan parasite in all three scallop species. Developmental forms observed in the shells appeared to include both sexual and asexual stages of the parasite, i.e. merogony, gametogony and sporogony, which suggests a monoxenous life cycle. Meronts, gamonts, zygotes and mature oocysts were solely found in the muscular tissue. Zoites, which could be sporozoites and/or merozoites, were observed in great numbers, most frequently in muscles, both intracellular and free in the extracellular space. Zoites were also common inside haemocytes. Examination of the ultrastructure showed that the zoites contained all the major structures characterizing apicomplexans. This apicomplexan parasite is morphologically different from other apicomplexan species previously described from bivalves. Presently, its systematic position within the phylum Apicomplexa cannot be ascertained. Copyright © 2011 Elsevier Inc. All rights reserved.
Penicillium araracuarense sp. nov., Penicillium elleniae sp. nov., Penicillium penarojense sp. nov., Penicillium vanderhammenii sp. nov. and Penicillium wotroi sp. nov., isolated from leaf litter.

PubMed

Houbraken, Jos; López-Quintero, Carlos A; Frisvad, Jens C; Boekhout, Teun; Theelen, Bart; Franco-Molano, Ana Esperanza; Samson, Robert A

2011-06-01

Several species of the genus Penicillium were isolated during a survey of the mycobiota of leaf litter and soil in Colombian Amazon forest. Five species, Penicillium penarojense sp. nov. (type strain CBS 113178(T) = IBT 23262(T)), Penicillium wotroi sp. nov. (type strain CBS 118171(T) = IBT 23253(T)), Penicillium araracuarense sp. nov. (type strain CBS 113149(T) = IBT 23247(T)), Penicillium elleniae sp. nov. (type strain CBS 118135(T) = IBT 23229(T)) and Penicillium vanderhammenii sp. nov. (type strain CBS 126216(T) = IBT 23203(T)) are described here as novel species. Their taxonomic novelty was determined using a polyphasic approach, combining phenotypic, molecular (ITS and partial β-tubulin sequences) and extrolite data. Phylogenetic analyses showed that each novel species formed a unique clade for both loci analysed and that they were most closely related to Penicillium simplicissimum, Penicillium janthinellum, Penicillium daleae and Penicillium brasilianum. An overview of the phylogeny of this taxonomically difficult group is presented, and 33 species are accepted. Each of the five novel species had a unique extrolite profile of known and uncharacterized metabolites and various compounds, such as penicillic acid, andrastin A, pulvilloric acid, paxillin, paspaline and janthitrem, were commonly produced by these phylogenetically related species. The novel species had a high growth rate on agar media, but could be distinguished from each other by several macro- and microscopical characteristics.
Three new Hepatozoon species (Apicomplexa: Hepatozoidae) infecting the Florida kingsnake, Lampropeltis getula floridana.

PubMed

Telford, Sam R

2010-02-01

The Florida kingsnake, Lampropeltis getula floridana, is host to 3 species of Hepatozoon at the type locality, Miramar, Broward County, Florida, and 2, possibly all 3, species at Cedar Key, Levy County, approximately 480 km to the northwest. Hepatozoon eurytopis, n. sp. was present also in Diadophis punctatus and Elaphe guttata in Jupiter Farms, Palm Beach County, and in Thamnophis sirtalis at Gainesville, Alachua County. Specific identity in D. punctatus was determined from gamont morphology and from sporogonic stages and gamont morphology in the infections obtained from E. guttata and T. sirtalis. Infection with all 3 species by ingestion of infected mosquitoes was easily obtained in E. guttata, but only H. eurytopis produced experimental infection in T. sirtalis and Storeria occipitomaculata. Hepatozoon eurytopis differed from the other 2 species, H. karyolysi n. sp. and H. rexi n. sp., by its short and broad, recurved gamonts with average dimensions 11.2-13.1 x 4.5-5.4 microm, length x maximum width (LW) 56-64 microm(2), and L/W ratios 2.13-2.80 in all host species, large round oocysts 95-303 x 91-285 microm, L/W ratios 1.03-1.05 with spherical to ovoid sporocysts 22-50 x 21-44 microm, L/W ratios 1.00-1.82 that contain 33.5-44.4 (16-76) sporozoites. The nucleus in immature gamonts is highly irregular, often fragmented in separate masses of chromatin, and commonly appears to form binucleate gamonts before maturity. Hepatozoon karyolysi has elongate, non-recurved gamonts, 15-20 x 4-7 microm, LW 64-143 microm(2), L/W ratios 2.3-4.5 that usually cause lysis or irregular margins of the nucleus in infected erythrocytes of the type host. Oocysts are spherical, 127-243 x 122-233 microm, L/W ratio 1.0-1.1 that contain spherical to usually ovoid sporocysts 17-30 x 17-24 microm, and produce 12-20 sporozoites. Gamonts of Hepatozoon rexi are non-recurved, 14-18 x 4-6 microm, LW 67-102 microm(2), and L/W ratio 2.8-4.1, and are usually surrounded by a prominent cyst wall within the host erythrocyte. Oocysts are nearly spherical, 103-178 x 103-172 microm, form usually elongate sporocysts, 30-39 x 20-25 microm L/W ratio 1.33-1.94 that contain 16-36 sporozoites. An oocyst of H. eurytopis was present in the salivary gland of an infected Aedes aegypti , which is the second report of sporogony by a Hepatozoon species occurring in this site.
Besnoitia neotomofelis n. sp. (Protozoa: Apicomplexa) from the southern plains woodrat ( Neotoma micropus).

PubMed

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.
Observations on associated histopathology with Aggregata octopiana infection (Protista: Apicomplexa) in Octopus vulgaris.

PubMed

Gestal, C; Abollo, E; Pascual, S

2002-06-21

Gamogony and sporogony of Aggregata octopiana were commonly observed during histological examination of the digestive tract of wild Octopus vulgaris from Ria de Vigo (NW Spain). A. octopiana infected noncuticularized caecum and intestine, and cuticularized oesophagus and crop. Infection was also observed in the gills and in covering mesenterium, mainly of the digestive gland and gonad. Histological and ultrastructural lesions associated with A. octopiana included host cell hypertrophy with nuclear displacement, inflammation, phagocytosis, ulceration and destruction of organ architecture. The possible existence of a malabsorption syndrome in the host is deduced.

Monocystis metaphirae sp. nov. (Protista: Apicomplexa: Monocystidae) from the earthworm Metaphire houlleti (Perrier).

PubMed

Bandyopadhyay, Probir K; Mallik, Partha; Göçmen, Bayram; Mitra, Amlan Kumar

2006-01-01

Biodiversity studies in search of endoparasitic acephaline gregarines revealed a new species of the genus Monocystis Stein, 1848 in the seminal vesicles of the earthworm Metaphire houlleti (Perrier) residing in alluvial soil of the district of North 24 Parganas. The new species is characterized by having bean-shaped gamonts measuring 94.0-151.0 (119.0+/-16.0) microm x 53.0-81.0(66.0+/-8.0) microm. The anterior end of the gamont is always wider than the posterior end. The mucron is always present at the wider end. The occurrence of syzygy (end to end, cauda-frontal) is a very rare feature which has been observed in the life cycle of the new species. The gametocyst is ovoid consisting of two unequal gamonts, measuring 85.0-102.0 microm (93.0+/-6.0). Oocysts are navicular in shape, measuring 6.5-11.0 (9.0+/-1.1) microm x 4.0-7.5 (5.5+/-1.9) microm.
Besnoitia neotomofelis n. sp. (Protozoa: Apicomplexa) from the southern plains woodrat (Neotoma micropus)

USDA-ARS?s Scientific Manuscript database

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 out bred Swiss W...
Hepatozoon ellisgreineri n. sp. (Hepatozoidae): description of the first avian apicomplexan blood parasite inhabiting granulocytes.

PubMed

Valkiūnas, Gediminas; Mobley, Kristin; Iezhova, Tatjana A

2016-02-01

Blood parasites of the genus Hepatozoon (Apicomplexa, Hepatozoidae) infect all groups of terrestrial vertebrates, and particularly high prevalence and species diversity have been reported in reptiles and mammals. A few morphologically similar species, in which gamonts inhabit mononuclear leukocytes and red blood cells, have been described in birds. Here, we report a new Hepatozoon species, which was found in wild-caught secretary birds Sagittarius serpentarius, from Tanzania. Hepatozoon ellisgreineri n. sp. can be readily distinguished from all described species of avian Hepatozoon because its gamonts develop only in granulocytes, predominantly in heterophils, a unique characteristic among bird parasites of this genus. Additionally, this is the first reported avian apicomplexan blood parasite, which inhabits and matures in granulocytes. We describe H. ellisgreineri based on morphological characteristics of blood stages and their host cells. This finding broadens knowledge about host cells of avian Hepatozoon spp. and other avian apicomplexan blood parasites, contributing to the better understanding of the diversity of haematozoa. This is the first report of hepatozoonosis in endangered African birds of the Sagittariidae.
Intravacuolar Membranes Regulate CD8 T Cell Recognition of Membrane-Bound Toxoplasma gondii Protective Antigen.

PubMed

Lopez, Jodie; Bittame, Amina; Massera, Céline; Vasseur, Virginie; Effantin, Grégory; Valat, Anne; Buaillon, Célia; Allart, Sophie; Fox, Barbara A; Rommereim, Leah M; Bzik, David J; Schoehn, Guy; Weissenhorn, Winfried; Dubremetz, Jean-François; Gagnon, Jean; Mercier, Corinne; Cesbron-Delauw, Marie-France; Blanchard, Nicolas

2015-12-15

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. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.
Phylogenetic evidence for an ancestral coevolution between a major clade of coccidian parasites and elasmobranch hosts.

PubMed

Xavier, Raquel; Santos, Joana L; Veríssimo, Ana

2018-05-01

Cartilaginous fishes are the oldest jawed vertebrates and are also reported to be the hosts of some of the most basal lineages of Cestoda and Aporocotylidae (Digenea) parasites. Recently a phylogenetic analysis of the coccidia (Apicomplexa) infecting marine vertebrates revealed that the lesser spotted dogfish harbours parasite lineages basal to Eimeria Schneider, 1875 and the group formed by Schellackia Reichenow, 1919, Lankesterella Ames, 1923, Caryospora Leger, 1904 and Isospora Schneider, 1881. In the present study we have found additional lineages of coccidian parasites infecting the cownose ray Rhinoptera bonasus Mitchill and the blue shark Prionace glauca Linnaeus. These lineages were also found as basal to species from the genera Lankesterella, Schellackia, Caryospora and Isospora infecting higher vertebrates. These results confirm previous phylogenetic assessments and suggest that these parasitic lineages first evolved in basal vertebrate hosts (i.e. Chondrichthyes), and that the more derived lineages infect higher vertebrates (e.g. birds and mammals) conforming to the evolution of their hosts. We hypothesise that elasmobranchs might host further ancestral parasite lineages harbouring unknown links of parasite evolution.
Chromerid genomes reveal the evolutionary path from photosynthetic algae to obligate intracellular parasites

PubMed Central

Woo, Yong H; Ansari, Hifzur; Otto, Thomas D; Klinger, Christen M; Kolisko, Martin; Michálek, Jan; Saxena, Alka; Shanmugam, Dhanasekaran; Tayyrov, Annageldi; Veluchamy, Alaguraj; Ali, Shahjahan; Bernal, Axel; del Campo, Javier; Cihlář, Jaromír; Flegontov, Pavel; Gornik, Sebastian G; Hajdušková, Eva; Horák, Aleš; Janouškovec, Jan; Katris, Nicholas J; Mast, Fred D; Miranda-Saavedra, Diego; Mourier, Tobias; Naeem, Raeece; Nair, Mridul; Panigrahi, Aswini K; Rawlings, Neil D; Padron-Regalado, Eriko; Ramaprasad, Abhinay; Samad, Nadira; Tomčala, Aleš; Wilkes, Jon; Neafsey, Daniel E; Doerig, Christian; Bowler, Chris; Keeling, Patrick J; Roos, David S; Dacks, Joel B; Templeton, Thomas J; Waller, Ross F; Lukeš, Julius; Oborník, Miroslav; Pain, Arnab

2015-01-01

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. DOI: http://dx.doi.org/10.7554/eLife.06974.001 PMID:26175406
Guidelines for the Detection of Babesia and Theileria Parasites.

PubMed

Lempereur, Laetitia; Beck, Relja; Fonseca, Isabel; Marques, Cátia; Duarte, Ana; Santos, Marcos; Zúquete, Sara; Gomes, Jacinto; Walder, Gernot; Domingos, Ana; Antunes, Sandra; Baneth, Gad; Silaghi, Cornelia; Holman, Patricia; Zintl, Annetta

2017-01-01

The genera Babesia and Theileria (phylum Apicomplexa, order Piroplasmida) are mainly transmitted by Ixodid ticks in which the sexual part of their life cycle followed by sporogony takes place. They include protozoan parasites that infect erythrocytes of a variety of vertebrate hosts, including domestic and wild animals, with some Babesia spp. also infecting humans. Babesia sporozoites transmitted in the tick's saliva during the bloodmeal directly infect erythrocytes, where they asexually multiply to produce pear-shaped merozoites in the process of merogony; whereas a pre-erythrocytic schizogonic life stage in leukocytes is found in Theileria and precedes merogony in the erythrocytes. The wide spectrum of Babesia and Theileria species and their dissimilar characteristics with relation to disease severity, transmission, epidemiology, and drug susceptibility stress the importance of accurate detection of babesiosis and theileriosis and their causative agents. These guidelines review the main methods currently used for the detection of Babesia and Theileria spp. for diagnostic purposes as well as epidemiological studies involving their vertebrate hosts and arthropod vectors. Serological methods were not included once they did not indicate current infection but rather exposure.
Population Abundance of Potentially Pathogenic Organisms in Intestinal Microbiome of Jungle Crow (Corvus macrorhynchos) Shown with 16S rRNA Gene-Based Microbial Community Analysis

PubMed Central

Maeda, Isamu; Siddiki, Mohammad Shohel Rana; Nozawa-Takeda, Tsutomu; Tsukahara, Naoki; Tani, Yuri; Naito, Taki; Sugita, Shoei

2013-01-01

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. PMID:24058905
Population abundance of potentially pathogenic organisms in intestinal microbiome of jungle crow (Corvus macrorhynchos) shown with 16S rRNA gene-based microbial community analysis.

PubMed

Maeda, Isamu; Siddiki, Mohammad Shohel Rana; Nozawa-Takeda, Tsutomu; Tsukahara, Naoki; Tani, Yuri; Naito, Taki; Sugita, Shoei

2013-01-01

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

PubMed Central

Kumpula, Esa-Pekka; Kursula, Inari

2015-01-01

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. PMID:25945702
Molecular cloning, sequencing, and expression of Eimeria tenella HSP70 partial gene.

PubMed

Bogado, A L G; Martins, G F; Sasse, J P; Guimarães, J da S; Garcia, J L

2017-03-15

Members of the Eimeria genus are protozoan parasites of the subphylum Apicomplexa (Eimeriidae family), and belong to the coccidia group. Eimeria tenella is one of the most pathogenic species owing to its ability to penetrate the mucosa, and cause inflammation and damage. It is an obligate intracellular parasite that causes disease by destroying the host cells during multiplication. Heat shock protein 70 (HSP70) is a molecular chaperone that prevents cellular stress. The objective of this study was to clone, sequence, and express E. tenella HSP70 protein. After selecting the region of highest hydrophilicity in the hsp70 gene, we cloned complementary DNA (cDNA) into a pTrcHis2-TOPO vector and transformed it into TOP10 Escherichia coli cells; after induction, the bacteria expressed a 23-kDa protein with insoluble expression levels of approximately 5 mg/L. In summary, the partial hsp70 gene was successfully expressed in E. coli, producing a 23-kDa protein under insoluble conditions, and the antigen characteristics predicted by hydrophilicity analysis suggest the development of a vaccine for use in avian coccidiosis.
An eight-year survey of the intestinal parasites of carnivores, hoofed mammals, primates, ratites and reptiles in the Ljubljana zoo in Slovenia.

PubMed

Kvapil, Pavel; Kastelic, Marjan; Dovc, Alenka; Bartova, Eva; Cizek, Petr; Lima, Natacha; Strus, Spela

2017-04-21

Problems with parasitic infections and their interspecies transmissions are common in zoological gardens and could pose serious health damage to captive animals. This study presents results of eight-year monitoring of intestinal parasites in animals from Zoo Ljubljana, Slovenia. A total of 741 faecal samples from 40 animal species were collected two to four times per year and examined microscopically. Intestinal parasites were detected in 45% of samples, with detection of helminths (Cestoda, Nematoda - Ascaridida, Enoplida, Strongylida, Oxyurida, Rhabditida and Trichurida) and protists (Apicomplexa and Ciliophora) in 25% and 13% of samples, respectively; mixed infection was found in 7% of samples. The mostly infected were ungulates (61%), followed by reptiles (44%), ratites (29%), primates (22%) and carnivores (7%). During the observation period, the number of infected animal species increased from 8 to 25. This is the first long-term monitoring study of intestinal parasites in zoo animals from Slovenia. Routine monitoring of parasitic infection and regular deworming and hygienic measures are necessary to prevent gastrointestinal infections in captive animals.
The moving junction of apicomplexan parasites: a key structure for invasion.

PubMed

Besteiro, Sébastien; Dubremetz, Jean-François; Lebrun, Maryse

2011-06-01

Most Apicomplexa are obligate intracellular parasites and many are important pathogens of human and domestic animals. For a successful cell invasion, they rely on their own motility and on a firm anchorage to their host cell, depending on the secretion of proteins and the establishment of a structure called the moving junction (MJ). The MJ moves from the apical to the posterior end of the parasite, leading to the internalization of the parasite into a parasitophorous vacuole. Based on recent data obtained in Plasmodium and Toxoplasma, an emerging model emphasizes a cooperative role of secreted parasitic proteins in building the MJ and driving this crucial invasive process. More precisely, the parasite exports the microneme protein AMA1 to its own surface and the rhoptry neck RON2 protein as a receptor inserted into the host cell together with other RON partners. Ongoing and future research will certainly help refining the model by characterizing the molecular organization within the MJ and its interactions with both host and parasite cytoskeleton for anchoring of the complex. © 2011 Blackwell Publishing Ltd.
Zoonotic Malaria – Global Overview and Research and Policy Needs

PubMed Central

Ramasamy, Ranjan

2014-01-01

The four main Plasmodium species that cause human malaria, Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae, and Plasmodium ovale, are transmitted between humans by mosquito vectors belonging to the genus Anopheles. It has recently become evident that Plasmodium knowlesi, a parasite that typically infects forest macaque monkeys, can be transmitted by anophelines to cause malaria in humans in Southeast Asia. Plasmodium knowlesi infections are frequently misdiagnosed microscopically as P. malariae. Direct human to human transmission of P. knowlesi by anophelines has not yet been established to occur in nature. Knowlesi malaria must therefore be presently considered a zoonotic disease. Polymerase chain reaction is now the definitive method for differentiating P. knowlesi from P. malariae and other human malaria parasites. The origin of P. falciparum and P. vivax in African apes are examples of ancient zoonoses that may be continuing at the present time with at least P. vivax, and possibly P. malariae and P. ovale. Other non-human primate malaria species, e.g., Plasmodium cynomolgi in Southeast Asia and Plasmodium brasilianum and Plasmodium simium in South America, can be transmitted to humans by mosquito vectors further emphasizing the potential for continuing zoonoses. The potential for zoonosis is influenced by human habitation and behavior as well as the adaptive capabilities of parasites and vectors. There is insufficient knowledge of the bionomics of Anopheles vector populations relevant to the cross-species transfer of malaria parasites and the real extent of malaria zoonoses. Appropriate strategies, based on more research, need to be developed for the prevention, diagnosis, and treatment of zoonotic malaria. PMID:25184118
First report of Hepatozoon (Apicomplexa: Adeleorina) in caecilians, with description of a new species.

PubMed

Harris, D James; Damas-Moreira, Isabel; Maia, João P M C; Perera, Ana

2014-02-01

Hepatozoon spp. are identified for the first time in the amphibian order Gymnophiona, or caecilians, from the Seychelles island of Silhouette. Estimate of relationships derived from partial 18S rRNA gene sequences indicate these are not related to Hepatozoon spp. from frogs or to other Hepatozoon spp. from reptiles in the Seychelles. Assessment of mature gamonts from blood smears indicate that these can be recognized as a new species, Hepatozoon seychellensis n. sp.
A new species of Choleoeimeria (apicomplexa: eimeriidae) from oustalet's chameleon, Furcifer oustaleti (Sauria: Chamaeleonidae).

PubMed

McAllister, Chris T

2012-02-01

One of three (33%) captive specimens of Oustalet's chameleon, Furcifer oustaleti (Mocquard) originally from Madagascar and housed at the Oklahoma City Zoological Park Herpetarium, Oklahoma County, Oklahoma, USA, was found to be passing an undescribed species of Choleoeimeria in its faeces. Oocysts of Choleoeimeria fischeri sp. n. were cylindroidal, 30.3 x 16.8 (28-34 x 15-18) microm, with a smooth, bilayered wall and a length/width ratio (L/W) of 1.8. A micropyle and oocyst residuum was absent but a fragmented polar granule was often present. Sporocysts were ovoidal, 9.6 x 8.0 (9-10 x 7-9) jm, with an L/W of 1.2. Stieda, sub-Stieda, and para-Stieda bodies were absent. The sporocyst residuum consists of large globules dispersed between sporozoites. Sporozoites were elongate, 8.6 x 2.9 (8-10 x 2-3) microm, with an elongate posterior refractile body. The new species represents the second coccidian described from this lizard.
A new species of Choleoeimeria (Apicomplexa: Eimeriidae) from Meller's chameleon, Trioceros melleri (Sauria: Chamaeleonidae).

PubMed

McAllister, Chris T

2012-10-01

A captive specimen of Meller's chameleon, Trioceros melleri (Gray), originally from Tanzania and housed at the Oklahoma City Zoological Park Herpetarium, Oklahoma County, Oklahoma, was found to be passing an undescribed species of Choleoeimeria in its feces. Oocysts of Choleoeimeria steveuptoni n. sp. were cylindroidal, 38.5 × 17.8 (36-42 × 17-19) µm with a bilayered wall and a shape index (length/width) of 2.2. A micropyle and oocyst residuum were absent, but a fragmented polar granule was often present. Ovoidal sporocysts were composed of 2 valves joined by a suture and measured 11.3 × 9.1 (11-12 × 9-10) µm; shape index of 1.3. Stieda, sub-Stieda, and para-Stieda bodies were absent. The sporocyst residuum consists of multiple globules dispersed along the perimeter of the sporocyst and between sporozoites. Sporozoites were elongate, 13.1 × 2.9 (12-15 × 2.6-3.2) µm with an elongate posterior refractile body. The new species represents the second coccidian documented from this lizard.
Prevalence of Haemoproteus spp. (Apicomplexa: Haemoproteidae) in tortoises in Brazil and its molecular phylogeny.

PubMed

Martinele, Isabel; Tostes, Raquel; Castro, Rômulo; D'Agosto, Marta

2016-01-01

Captive terrestrial tortoises of the species Chelonoidis carbonaria (n = 17) and Chelonoidis denticulata (n = 37) in the state of Minas Gerais, southeastern Brazil, were examined for hematozoans by using a combination of microscopic and molecular methods. Microscopic examination revealed young intra-erythrocytic forms in blood smears from both species of tortoises. The results of PCR, sequencing, and phylogenetic analysis indicated that these parasites belonged to the Haemoproteus spp., whose observed prevalence was 17.6 % in C. carbonaria and 13.5 % in C. denticulata. Phylogenetic analysis indicated that these sequences formed a clade that was grouped with other sequences of Haemoproteus spp. parasites in birds, separate from the clade formed by Haemoproteus spp. of reptiles. This study expands the information regarding the occurrence and distribution of hemosporidia in turtles and is the first study of blood parasites in C. carbonaria.
Complete mitochondrial genome sequences from five Eimeria species (Apicomplexa; Coccidia; Eimeriidae) infecting domestic turkeys

PubMed Central

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 mitotically replicating mitochondrial genome may be more suited for species level molecular work; however, only limited sequence data are available for Eimeria spp. infecting turkeys. The purpose of this study was to sequence and annotate the complete mitochondrial genomes from 5 Eimeria species that commonly infect the domestic turkey (Meleagris gallopavo). Methods Six single-oocyst derived cultures of five Eimeria species infecting turkeys were PCR-amplified and sequenced completely prior to detailed annotation. Resulting sequences were aligned and used in phylogenetic analyses (BI, ML, and MP) that included complete mitochondrial genomes from 16 Eimeria species or concatenated CDS sequences from each genome. Results Complete mitochondrial genome sequences were obtained for Eimeria adenoeides Guelph, 6211 bp; Eimeria dispersa Briston, 6238 bp; Eimeria meleagridis USAR97-01, 6212 bp; Eimeria meleagrimitis USMN08-01, 6165 bp; Eimeria gallopavonis Weybridge, 6215 bp; and Eimeria gallopavonis USKS06-01, 6215 bp). The order, orientation and CDS lengths of the three protein coding genes (COI, COIII and CytB) as well as rDNA fragments encoding ribosomal large and small subunit rRNA were conserved among all sequences. Pairwise sequence identities between species ranged from 88.1% to 98.2%; sequence variability was concentrated within CDS or between rDNA fragments (where indels were common). No phylogenetic reconstruction supported monophyly of Eimeria species infecting turkeys; Eimeria dispersa may have arisen via host switching from another avian host. Phylogenetic analyses suggest E. necatrix and E. tenella are related distantly to other Eimeria of chickens. Conclusions Mitochondrial genomes of Eimeria species sequenced to date are highly conserved with regard to gene content and structure. Nonetheless, complete mitochondrial genome sequences and, particularly the three CDS, possess sufficient sequence variability for differentiating Eimeria species of poultry. The mitochondrial genome sequences are highly suited for molecular diagnostics and phylogenetics of coccidia and, potentially, genetic markers for molecular epidemiology. PMID:25034633
A new species of Eimeria (Apicomplexa: Eimeriidae) from Californian rabbits in Hebei Province, China.

PubMed

Cui, Ping; Liu, Hongbin; Fang, Sufang; Gu, Xiaolong; Wang, Peng; Liu, Chunling; Tao, Geru; Liu, Xianyong; Suo, Xun

2017-10-01

Rabbit coccidiosis is caused by infection with one or usually several Eimeria species, parasitizing in hepatobiliary ducts or intestinal epithelium of rabbits. To date, 11 species of rabbit coccidia have been well documented. Here we report a new species of Eimeria from rabbits. Sporulated oocysts were ellipsoidal to slightly ovoidal, 37.4 (32.6-41.2) μm in length, 23.5 (20.9-25.5) μm in width, with a shape index (length/width) 1.6 (1.43-1.91) and smooth, bilayered, homogeneously thick wall. The micropyle was obvious and with an inner diameter of 6.2 (5.0-7.5) μm. Both oocyst residuum and polar granule were absent. Sporocysts were ellipsoidal to elongate, 17.2 (13.2-20.0) μm long and 8.4 (7.5-9.1) μm wide, with a shape index (length/width) of 2.1 (1.74-2.21) and the presence of Stieda body and sporocyst residuum. The prepatent period was 132h. Phylogenetic analysis showed that 18S rDNA sequence of the new species clustered together with the 11 rabbit Eimeria species into a clade. However, ITS-1 sequence of the new species shared low similarities (27.1%-30%) with those of 11 rabbit Eimeria species. As the data above supported the erection of a new species, we named it as Eimeria kongi n. sp., in honor of Fanyao Kong, a Chinese parasitologist. The finding of the new species has important implications for the diagnosis and prevention of rabbit coccidiosis. Copyright © 2017. Published by Elsevier B.V.

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

PubMed

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

2014-07-17

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 mitotically replicating mitochondrial genome may be more suited for species level molecular work; however, only limited sequence data are available for Eimeria spp. infecting turkeys. The purpose of this study was to sequence and annotate the complete mitochondrial genomes from 5 Eimeria species that commonly infect the domestic turkey (Meleagris gallopavo). Six single-oocyst derived cultures of five Eimeria species infecting turkeys were PCR-amplified and sequenced completely prior to detailed annotation. Resulting sequences were aligned and used in phylogenetic analyses (BI, ML, and MP) that included complete mitochondrial genomes from 16 Eimeria species or concatenated CDS sequences from each genome. Complete mitochondrial genome sequences were obtained for Eimeria adenoeides Guelph, 6211 bp; Eimeria dispersa Briston, 6238 bp; Eimeria meleagridis USAR97-01, 6212 bp; Eimeria meleagrimitis USMN08-01, 6165 bp; Eimeria gallopavonis Weybridge, 6215 bp; and Eimeria gallopavonis USKS06-01, 6215 bp). The order, orientation and CDS lengths of the three protein coding genes (COI, COIII and CytB) as well as rDNA fragments encoding ribosomal large and small subunit rRNA were conserved among all sequences. Pairwise sequence identities between species ranged from 88.1% to 98.2%; sequence variability was concentrated within CDS or between rDNA fragments (where indels were common). No phylogenetic reconstruction supported monophyly of Eimeria species infecting turkeys; Eimeria dispersa may have arisen via host switching from another avian host. Phylogenetic analyses suggest E. necatrix and E. tenella are related distantly to other Eimeria of chickens. Mitochondrial genomes of Eimeria species sequenced to date are highly conserved with regard to gene content and structure. Nonetheless, complete mitochondrial genome sequences and, particularly the three CDS, possess sufficient sequence variability for differentiating Eimeria species of poultry. The mitochondrial genome sequences are highly suited for molecular diagnostics and phylogenetics of coccidia and, potentially, genetic markers for molecular epidemiology.
Eimeria collieie n. sp. (Apicomplexa:Eimeriidae) from the western long-necked turtle (Chelodina colliei).

PubMed

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. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.
Phylogenetic position of the genus Perkinsus (Protista, Apicomplexa) based on small subunit ribosomal RNA.

PubMed

Goggin, C L; Barker, S C

1993-07-01

Parasites of the genus Perkinsus destroy marine molluscs worldwide. Their phylogenetic position within the kingdom Protista is controversial. Nucleotide sequence data (1792 bp) from the small subunit rRNA gene of Perkinsus sp. from Anadara trapezia (Mollusca: Bivalvia) from Moreton Bay, Queensland, was used to examine the phylogenetic affinities of this enigmatic genus. These data were aligned with nucleotide sequences from 6 apicomplexans, 3 ciliates, 3 flagellates, a dinoflagellate, 3 fungi, maize and human. Phylogenetic trees were constructed after analysis with maximum parsimony and distance matrix methods. Our analyses indicate that Perkinsus is phylogenetically closer to dinoflagellates and to coccidean and piroplasm apicomplexans than to fungi or flagellates.
A global map of genetic diversity in Babesia microti reveals strong population structure and identifies variants associated with clinical relapse

PubMed Central

Lemieux, Jacob E.; Tran, Alice D.; Freimark, Lisa; Schaffner, Stephen F.; Goethert, Heidi; Andersen, Kristian G.; Bazner, Suzane; Li, Amy; McGrath, Graham; Sloan, Lynne; Vannier, Edouard; Milner, Dan; Pritt, Bobbi; Rosenberg, Eric; Telford, Sam; Bailey, Jeffrey A.; Sabeti, Pardis C.

2017-01-01

Human babesiosis caused by Babesia microti is an emerging tick-borne zoonosis of increasing importance due to rising incidence and expanding geographic range1. Infection with this organism, an intraerythrocytic parasite of the phylum Apicomplexa, causes a febrile syndrome similar to malaria2. Relapsing disease is common among immunocompromised and asplenic individuals3,4, and drug resistance has recently been reported5. To investigate the origin and genetic diversity of this parasite, we sequenced the complete genomes of 42 B. microti samples from around the world, including deep coverage of clinical infections at endemic sites in the continental United States. Samples from the continental US segregate into a Northeast lineage and a Midwest lineage, with subsequent divergence of subpopulations along geographic lines. We identify parasite variants that associate with relapsing disease, including amino acid substitutions in the atovaquone-binding regions of cytochrome b (cytb) and the azithromycin-binding region of ribosomal protein subunit L4 (rpl4). Our results shed light on the origin, diversity, and evolution of B. microti, suggest possible mechanisms for clinical relapse, and create the foundation for further research on this emerging pathogen. PMID:27572973
A global map of genetic diversity in Babesia microti reveals strong population structure and identifies variants associated with clinical relapse.

PubMed

Lemieux, Jacob E; Tran, Alice D; Freimark, Lisa; Schaffner, Stephen F; Goethert, Heidi; Andersen, Kristian G; Bazner, Suzane; Li, Amy; McGrath, Graham; Sloan, Lynne; Vannier, Edouard; Milner, Dan; Pritt, Bobbi; Rosenberg, Eric; Telford, Sam; Bailey, Jeffrey A; Sabeti, Pardis C

2016-06-13

Human babesiosis caused by Babesia microti is an emerging tick-borne zoonosis of increasing importance due to its rising incidence and expanding geographic range(1). Infection with this organism, an intraerythrocytic parasite of the phylum Apicomplexa, causes a febrile syndrome similar to malaria(2). Relapsing disease is common among immunocompromised and asplenic individuals(3,4) and drug resistance has recently been reported(5). To investigate the origin and genetic diversity of this parasite, we sequenced the complete genomes of 42 B. microti samples from around the world, including deep coverage of clinical infections at endemic sites in the continental USA. Samples from the continental USA segregate into a Northeast lineage and a Midwest lineage, with subsequent divergence of subpopulations along geographic lines. We identify parasite variants that associate with relapsing disease, including amino acid substitutions in the atovaquone-binding regions of cytochrome b (cytb) and the azithromycin-binding region of ribosomal protein subunit L4 (rpl4). Our results shed light on the origin, diversity and evolution of B. microti, suggest possible mechanisms for clinical relapse, and create the foundation for further research on this emerging pathogen.
Apicomplexan profilins in vaccine development applied to bovine neosporosis.

PubMed

Mansilla, Florencia C; Capozzo, Alejandra V

2017-12-01

Neospora caninum, an intracellular protozoan parasite from the phylum Apicomplexa, is the etiologic agent of neosporosis, a disease considered as a major cause of reproductive loss in cattle and neuromuscular disease in dogs. Bovine neosporosis has a great economic impact in both meat and dairy industries, related to abortion, premature culling and reduced milk yields. Although many efforts have been made to restrain bovine neosporosis, there are still no efficacious control methods. Many vaccine-development studies focused in the apicomplexan proteins involved in the adhesion and invasion of the host cell. Among these proteins, profilins have recently emerged as potential vaccine antigens or even adjuvant candidates for several diseases caused by apicomplexan parasites. Profilins bind Toll-like receptors 11 and 12 initiating MyD88 signaling, that triggers IL-12 and IFN-γ production, which may promote protection against infection. Here we summarized the state-of-the-art of novel vaccine development based on apicomplexan profilins applied as antigens or adjuvants, and delved into recent advances on N. caninum vaccines using profilin in the mouse model and in cattle. Copyright © 2017 Elsevier Inc. All rights reserved.
Evidence of Taxa-, Clone-, and Kin-discrimination in Protists: Ecological and Evolutionary Implications.

PubMed

Espinosa, Avelina; Paz-Y-Miño-C, Guillermo

2014-11-01

Unicellular eukaryotes, or protists, are among the most ancient organisms on Earth. Protists belong to multiple taxonomic groups; they are widely distributed geographically and in all environments. Their ability to discriminate among con- and heterospecifics has been documented during the past decade. Here we discuss exemplar cases of taxa-, clone-, and possible kin-discrimination in five major lineages: Mycetozoa ( Dictyostelium , Polysphondylium ), Dikarya ( Saccharomyces ), Ciliophora ( Tetrahymena ), Apicomplexa ( Plasmodium ) and Archamoebae ( Entamoeba ). We summarize the proposed genetic mechanisms involved in discrimination-mediated aggregation (self versus different), including the csA , FLO and trg (formerly lag ) genes, and the Proliferation Activation Factors (PAFs), which facilitate clustering in some protistan taxa. We caution about the experimental challenges intrinsic to studying recognition in protists, and highlight the opportunities for exploring the ecology and evolution of complex forms of cell-cell communication, including social behavior, in a polyphyletic, still superficially understood group of organisms. Because unicellular eukaryotes are the evolutionary precursors of multicellular life, we infer that their mechanisms of taxa-, clone-, and possible kin-discrimination gave origin to the complex diversification and sophistication of traits associated with species and kin recognition in plants, fungi, invertebrates and vertebrates.
Evidence of Taxa-, Clone-, and Kin-discrimination in Protists: Ecological and Evolutionary Implications

PubMed Central

Espinosa, Avelina; Paz-y-Miño-C, Guillermo

2014-01-01

Unicellular eukaryotes, or protists, are among the most ancient organisms on Earth. Protists belong to multiple taxonomic groups; they are widely distributed geographically and in all environments. Their ability to discriminate among con- and heterospecifics has been documented during the past decade. Here we discuss exemplar cases of taxa-, clone-, and possible kin-discrimination in five major lineages: Mycetozoa (Dictyostelium, Polysphondylium), Dikarya (Saccharomyces), Ciliophora (Tetrahymena), Apicomplexa (Plasmodium) and Archamoebae (Entamoeba). We summarize the proposed genetic mechanisms involved in discrimination-mediated aggregation (self versus different), including the csA, FLO and trg (formerly lag) genes, and the Proliferation Activation Factors (PAFs), which facilitate clustering in some protistan taxa. We caution about the experimental challenges intrinsic to studying recognition in protists, and highlight the opportunities for exploring the ecology and evolution of complex forms of cell-cell communication, including social behavior, in a polyphyletic, still superficially understood group of organisms. Because unicellular eukaryotes are the evolutionary precursors of multicellular life, we infer that their mechanisms of taxa-, clone-, and possible kin-discrimination gave origin to the complex diversification and sophistication of traits associated with species and kin recognition in plants, fungi, invertebrates and vertebrates. PMID:25400313
Haemogregarina podocnemis sp. nov.: description of a new species of Haemogregarina Danilewsky 1885 (Adeleina: Haemogregarinaidae) in free-living and captive yellow-spotted river turtles Podocnemis unifilis (Testudines: Podocnemididae) from Brazil.

PubMed

Úngari, Letícia Pereira; Santos, André Luiz Quagliatto; O'Dwyer, Lucia Helena; da Silva, Maria Regina Lucas; de Melo Fava, Natália Nasser; Paiva, Guilherme Carrara Moreira; de Melo Costa Pinto, Rogério; Cury, Márcia Cristina

2018-05-01

Based on morphological, morphometric, and molecular data, we describe a new hemoparasite of the genus Haemogregarina Danilewsky 1885, isolated from the Brazilian aquatic turtle Podocnemis unifilis (Testudines: Podocnemididae). The new species, Haemogregarina podocnemis sp. nov. (Apicomplexa: Haemogregarinidae), is characterized by small trophozoites with a single cytoplasmic vacuole on one side; pre-meronts with nuclear chromatin dispersed in the cytoplasm, with or without cytoplasmic vacuoles; meronts that are usually broad and slightly curved (kidney-shaped), with an average of eight small rectangular nuclei; immature gamonts (bean-shaped) with two morphological types: one with nuclear chromatin dispersed in the cytoplasm and the other with nuclei in the middle of the cell; mature gamonts of two morphological types: one with a length equal to or greater than that of the erythrocyte and the width of the nuclei similar to that of the hemoparasite and the other smaller than the erythrocyte with the width of the nuclei less than that of the hemoparasite. This is the first hemogregarine species described that infects the Brazilian turtle Po. unifilis. These findings highlight the need for further studies of Haemogregarina spp. to better determine the biodiversity of this understudied parasite group.
Characterization of the Chloroquine Resistance Transporter Homologue in Toxoplasma gondii

PubMed Central

Warring, Sally D.; Dou, Zhicheng; Carruthers, Vern B.; McFadden, Geoffrey I.

2014-01-01

Mutations in the Plasmodium falciparum chloroquine resistance transporter (PfCRT) protein confer resistance to the antimalarial drug chloroquine. PfCRT localizes to the parasite digestive vacuole, the site of chloroquine action, where it mediates resistance by transporting chloroquine out of the digestive vacuole. PfCRT belongs to a family of transporter proteins called the chloroquine resistance transporter family. CRT family proteins are found throughout the Apicomplexa, in some protists, and in plants. Despite the importance of PfCRT in drug resistance, little is known about the evolution or native function of CRT proteins. The apicomplexan parasite Toxoplasma gondii contains one CRT family protein. We demonstrate that T. gondii CRT (TgCRT) colocalizes with markers for the vacuolar (VAC) compartment in these parasites. The TgCRT-containing VAC is a highly dynamic organelle, changing its morphology and protein composition between intracellular and extracellular forms of the parasite. Regulated knockdown of TgCRT expression resulted in modest reduction in parasite fitness and swelling of the VAC, indicating that TgCRT contributes to parasite growth and VAC physiology. Together, our findings provide new information on the role of CRT family proteins in apicomplexan parasites. PMID:24859994
Host associations and turnover of haemosporidian parasites in manakins (Aves: Pipridae).

PubMed

Fecchio, Alan; Svensson-Coelho, Maria; Bell, Jeffrey; Ellis, Vincenzo A; Medeiros, Matthew C; Trisos, Christopher H; Blake, John G; Loiselle, Bette A; Tobias, Joseph A; Fanti, Rebeka; Coffey, Elyse D; DE Faria, Iubatã P; Pinho, João B; Felix, Gabriel; Braga, Erika M; Anciães, Marina; Tkach, Vasyl; Bates, John; Witt, Christopher; Weckstein, Jason D; Ricklefs, Robert E; Farias, Izeni P

2017-06-01

Parasites of the genera Plasmodium and Haemoproteus (Apicomplexa: Haemosporida) are a diverse group of pathogens that infect birds nearly worldwide. Despite their ubiquity, the ecological and evolutionary factors that shape the diversity and distribution of these protozoan parasites among avian communities and geographic regions are poorly understood. Based on a survey throughout the Neotropics of the haemosporidian parasites infecting manakins (Pipridae), a family of Passerine birds endemic to this region, we asked whether host relatedness, ecological similarity and geographic proximity structure parasite turnover between manakin species and local manakin assemblages. We used molecular methods to screen 1343 individuals of 30 manakin species for the presence of parasites. We found no significant correlations between manakin parasite lineage turnover and both manakin species turnover and geographic distance. Climate differences, species turnover in the larger bird community and parasite lineage turnover in non-manakin hosts did not correlate with manakin parasite lineage turnover. We also found no evidence that manakin parasite lineage turnover among host species correlates with range overlap and genetic divergence among hosts. Our analyses indicate that host switching (turnover among host species) and dispersal (turnover among locations) of haemosporidian parasites in manakins are not constrained at this scale.
Towards a molecular understanding of the apicomplexan actin motor: on a road to novel targets for malaria remedies?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kumpula, Esa-Pekka; Helmholtz Centre for Infection Research, Notkestrasse 85, 22607 Hamburg; German Electron Synchrotron, Notkestrasse 85, 22607 Hamburg

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 withmore » 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.« less
Ecology of malaria parasites infecting Southeast Asian macaques: evidence from cytochrome b sequences

PubMed Central

Putaporntip, Chaturong; Jongwutiwes, Somchai; Thongaree, Siriporn; Seethamchai, Sunee; Grynberg, Priscila; Hughes, Austin L.

2010-01-01

Although malaria parasites infecting non-human primates are important models for human malaria, little is known of the ecology of infection by these parasites in the wild. We extensively sequenced cytochrome b (cytb) of malaria parasites (Apicomplexa: Haemosporida) from free-living Southeast Asian monkeys Macaca nemestrina and M. fascicularis. The two most commonly observed taxa were P. inui and Hepatocystis sp., but certain other sequences did not cluster closely with any previously sequenced species. Most of the major clades of parasites were found in both Macaca species; and the two most commonly occurring parasite infected the two Macaca species at approximately equal levels. However, P. inui showed evidence of genetic differentiation between the populations infecting the two Macaca species, suggesting limited movement of this parasite among hosts. Moreover, coinfection with Plasmodium and Hepatocystis species occurred significantly less frequently than expected on the basis of the rates of infection with either taxon alone, suggesting the possibility of competitive exclusion. The results revealed unexpectedly complex communities of Plasmodium and Hepatocystis taxa infecting wild Southeast Asian monkeys. Parasite taxa differed with respect to both the frequency of between-host movement and their frequency of coinfection. PMID:20646216
Genetic dissection of floridean starch synthesis in the cytosol of the model dinoflagellate Crypthecodinium cohnii

PubMed Central

Dauvillée, David; Deschamps, Philippe; Ral, Jean-Philippe; Plancke, Charlotte; Putaux, Jean-Luc; Devassine, Jimi; Durand-Terrasson, Amandine; Devin, Aline; Ball, Steven G.

2009-01-01

Starch defines an insoluble semicrystalline form of storage polysaccharides restricted to Archaeplastida (red and green algae, land plants, and glaucophytes) and some secondary endosymbiosis derivatives of the latter. While green algae and land-plants store starch in plastids by using an ADP-glucose-based pathway related to that of cyanobacteria, red algae, glaucophytes, cryptophytes, dinoflagellates, and apicomplexa parasites store a similar type of polysaccharide named floridean starch in their cytosol or periplast. These organisms are suspected to store their floridean starch from UDP-glucose in a fashion similar to heterotrophic eukaryotes. However, experimental proof of this suspicion has never been produced. Dinoflagellates define an important group of both photoautotrophic and heterotrophic protists. We now report the selection and characterization of a low starch mutant of the heterotrophic dinoflagellate Crypthecodinium cohnii. We show that the sta1-1 mutation of C. cohnii leads to a modification of the UDP-glucose-specific soluble starch synthase activity that correlates with a decrease in starch content and an alteration of amylopectin structure. These experimental results validate the UDP-glucose-based pathway proposed for floridean starch synthesis. PMID:19940244
A Knockout Screen of ApiAP2 Genes Reveals Networks of Interacting Transcriptional Regulators Controlling the Plasmodium Life Cycle.

PubMed

Modrzynska, Katarzyna; Pfander, Claudia; Chappell, Lia; Yu, Lu; Suarez, Catherine; Dundas, Kirsten; Gomes, Ana Rita; Goulding, David; Rayner, Julian C; Choudhary, Jyoti; Billker, Oliver

2017-01-11

A family of apicomplexa-specific proteins containing AP2 DNA-binding domains (ApiAP2s) was identified in malaria parasites. This family includes sequence-specific transcription factors that are key regulators of development. However, functions for the majority of ApiAP2 genes remain unknown. Here, a systematic knockout screen in Plasmodium berghei identified ten ApiAP2 genes that were essential for mosquito transmission: four were critical for the formation of infectious ookinetes, and three were required for sporogony. We describe non-essential functions for AP2-O and AP2-SP proteins in blood stages, and identify AP2-G2 as a repressor active in both asexual and sexual stages. Comparative transcriptomics across mutants and developmental stages revealed clusters of co-regulated genes with shared cis promoter elements, whose expression can be controlled positively or negatively by different ApiAP2 factors. We propose that stage-specific interactions between ApiAP2 proteins on partly overlapping sets of target genes generate the complex transcriptional network that controls the Plasmodium life cycle. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.
Prevalence of protozoa species in drinking and environmental water sources in Sudan.

PubMed

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.
Sarcocystid organisms found in bile from a dog with acute hepatitis: a case report and review of intestinal and hepatobiliary Sarcocystidae infections in dogs and cats.

PubMed

Irvine, Katherine L; Walker, Julie M; Friedrichs, Kristen R

2016-03-01

Sarcocystidae is a family of coccidian protozoa from the phylum Apicomplexa that includes Toxoplasma, Neospora, Sarcocystis, Hammondia, and Besnoitia spp. All species undergo a 2-host sexual and asexual cycle. In the definitive host, replication is enteroepithelial, and infection is typically asymptomatic or less commonly causes mild diarrhea. Clinical disease is most frequently observed in the intermediate host, often as an aberrant infection, and is mostly associated with neurologic, muscular, or hepatic inflammation. Here, we review the literature regarding intestinal Sarcocystidae infections in dogs and cats, with emphasis on the life cycle stages and the available diagnostic assays and their limitations. We also report the diagnostic findings for an 11-year-old dog with acute neutrophilic hepatitis, biliary protozoa, and negative biliary culture. Although Toxoplasma and Neospora IgG titers were both high, PCR for these 2 organisms was negative for bile. The organisms were identified by 18S rDNA PCR as most consistent with Hammondia, either H heydorni or H triffittae. This is the first report of presumed Hammondia organisms being found in canine bile. © 2016 American Society for Veterinary Clinical Pathology.
More Membranes, more Proteins: Complex Protein Import Mechanisms into Secondary Plastids

PubMed Central

Agrawal, Swati; Striepen, Boris

2010-01-01

Plastids are found across the tree of life in a tremendous diversity of life forms. Surprisingly they are not limited to photosynthetic organisms but also found in numerous predators and parasites. An important reason for the pervasiveness of plastids has been their ability to move laterally and to jump from one branch of the tree of life to the next through secondary endosymbiosis. Eukaryotic algae have entered endosymbiotic relationships with other eukaryotes on multiple independent occasions. The descendants of these endosymbiotic events now carry complex plastids, organelles that are bound by three or even four membranes. As in all endosymbiotic organelles most of the symbiont’s genes have been transferred to the host and their protein products have to be imported into the organelle. As four membranes might suggest, this is a complex process. The emerging mechanisms display a series of translocons that mirror the divergent ancestry of the membranes they cross. This review is written from a parasite biologist viewpoint and seeks to provide a brief overview of plastid evolution in particular for readers not already familiar with plant and algal biology and then focuses on recent molecular discoveries using genetically tractable Apicomplexa and diatoms. PMID:21036664
IDENTIFICATION OF TWO NOVEL COCCIDIAN SPECIES SHED BY CALIFORNIA SEA LIONS (ZALOPHUS CALIFORNIANUS)

PubMed Central

Carlson-Bremer, Daphne; Johnson, Christine K.; Miller, Robin H.; Gulland, Frances M. D.; Conrad, Patricia A.; Wasmuth, James D.; Colegrove, Kathleen M.

2016-01-01

Routine fecal examination revealed novel coccidian oocysts in asymptomatic California sea lions (Zalophus californianus) in a rehabilitation facility. Coccidian oocysts were observed in fecal samples collected from 15 of 410 California sea lions admitted to The Marine Mammal Center between April 2007 and October 2009. Phylogenetic analysis using the full ITS-1 region, partial small subunit 18S rDNA sequence, and the Apicomplexa rpoB region identified 2 distinct sequence clades, referred to as Coccidia A and Coccidia B, and placed them in the Sarcocystidae, grouped with the tissue-cyst–forming coccidia. Both sequence clades resolved as individual taxa at ITS-1 and rpoB and were most closely related to Neospora caninum. Coccidia A was identified in 11 and Coccidia B in 4 of 12 sea lion oocyst samples successfully sequenced (3 of those sea lions were co-infected with both parasites). Shedding of Coccidia A oocysts was not associated with age class, sex, or stranding location, but yearlings represented the majority of shedders (8/15). This is the first study to use molecular phylogenetics to identify and describe coccidian parasites shed by a marine mammal. PMID:22091999
Identification of two novel coccidian species shed by California sea lions (Zalophus californianus).

PubMed

Carlson-Bremer, Daphne; Johnson, Christine K; Miller, Robin H; Gulland, Frances M D; Conrad, Patricia A; Wasmuth, James D; Colegrove, Kathleen M; Grigg, Michael E

2012-04-01

Routine fecal examination revealed novel coccidian oocysts in asymptomatic California sea lions (Zalophus californianus) in a rehabilitation facility. Coccidian oocysts were observed in fecal samples collected from 15 of 410 California sea lions admitted to The Marine Mammal Center between April 2007 and October 2009. Phylogenetic analysis using the full ITS-1 region, partial small subunit 18S rDNA sequence, and the Apicomplexa rpoB region identified 2 distinct sequence clades, referred to as Coccidia A and Coccidia B, and placed them in the Sarcocystidae, grouped with the tissue-cyst-forming coccidia. Both sequence clades resolved as individual taxa at ITS-1 and rpoB and were most closely related to Neospora caninum. Coccidia A was identified in 11 and Coccidia B in 4 of 12 sea lion oocyst samples successfully sequenced (3 of those sea lions were co-infected with both parasites). Shedding of Coccidia A oocysts was not associated with age class, sex, or stranding location, but yearlings represented the majority of shedders (8/15). This is the first study to use molecular phylogenetics to identify and describe coccidian parasites shed by a marine mammal.

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

PubMed

Ceuta, L O; Boehs, G

2012-08-01

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.
First Case of Canine Infection with Hepatozoon canis (Apicomplexa: Haemogregarinidae) in the Republic of Korea.

PubMed

Kwon, Seung-Joo; Kim, Yoon-Hee; Oh, Hyun-Hee; Choi, Ul-Soo

2017-10-01

This report describes a dog infected with Hepatozoon canis, the first canine infection in the Republic of Korea. A 2-year-old intact male Maltese dog presented with anorexia and depression. Physical examinations revealed mild dehydration and hyperthermia (39.8°C), and blood analysis showed pancytopenia. Diff-Quik staining of blood smear specimens showed the presence of ellipsoidal shaped structures (gamonts of H. canis) within a small number of neutrophils. Real-time PCR analysis using whole blood confirmed infection by H. canis. The clinical condition of the dog improved after symptomatic treatment and administration of doxycycline. Although a molecular epidemiologic survey in Korea showed H. canis infection of dogs, to our knowledge this is the first report of a dog infection in Korea molecularly shown to be H. canis.
First Case of Canine Infection with Hepatozoon canis (Apicomplexa: Haemogregarinidae) in the Republic of Korea

PubMed Central

Kwon, Seung-Joo; Kim, Yoon-Hee; Oh, Hyun-Hee; Choi, Ul-Soo

2017-01-01

This report describes a dog infected with Hepatozoon canis, the first canine infection in the Republic of Korea. A 2-year-old intact male Maltese dog presented with anorexia and depression. Physical examinations revealed mild dehydration and hyperthermia (39.8°C), and blood analysis showed pancytopenia. Diff-Quik staining of blood smear specimens showed the presence of ellipsoidal shaped structures (gamonts of H. canis) within a small number of neutrophils. Real-time PCR analysis using whole blood confirmed infection by H. canis. The clinical condition of the dog improved after symptomatic treatment and administration of doxycycline. Although a molecular epidemiologic survey in Korea showed H. canis infection of dogs, to our knowledge this is the first report of a dog infection in Korea molecularly shown to be H. canis. PMID:29103272
Acquisition and transmission of Hepatozoon canis (Apicomplexa: Hepatozoidae) by the tick Amblyomma ovale (Acari: Ixodidae).

PubMed

Rubini, A S; Paduan, K S; Martins, T F; Labruna, M B; O'Dwyer, L H

2009-10-14

The present study aimed to evaluate under controlled conditions the acquisition of Hepatozoon canis by Amblyomma ovale after feeding on infected dogs, and the subsequent induction of infection in uninfected dogs that ingested the experimentally infected ticks. Two H. canis naturally infected dogs were infested with A. ovale adult ticks derived from an uninfected laboratory tick colony. After feeding, two A. ovale females presented H. canis oocysts in the hemolymph at the first and fourth days after removal of ticks from dogs. The oocysts had an average size of 244.34 microm x 255.46 microm. Three uninfected dogs were fed with ticks previously fed on the infected dogs. Only one dog became infected 32 days after oral inoculation, presenting circulating gametocytes, parasitemia less than 1%, and positive PCR confirmed to be H. canis by DNA sequencing. The results obtained indicated A. ovale ticks as potential vector of H. canis in rural areas of Brazil.
Three new species of Coccidia (Apicomplexa: Eimeriidae) from Skinks, Lipinia spp. (Sauria: Scincidae), from Oceania

USGS Publications Warehouse

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.
Has Sarcocystis neurona Dubey et al., 1991 (Sporozoa: Apicomplexa: Sarcocystidae) cospeciated with its intermediate hosts?

PubMed

Elsheikha, Hany M

2009-08-26

The question of how Sarcocystis neurona is able to overcome species barrier and adapt to new hosts is central to the understanding of both the evolutionary origin of S. neurona and the prediction of its field host range. Therefore, it is worth reviewing current knowledge on S. neurona host specificity. The available host range data for S. neurona are discussed in relation to a subject of evolutionary importance-specialist or generalist and its implications to understand the strategies of host adaptation. Current evidences demonstrate that a wide range of hosts exists for S. neurona. This parasite tends to be highly specific for its definitive host but much less so for its intermediate host (I.H.). The unique specificity of S. neurona for its definitive host may be mediated by a probable long coevolutionary relationship of the parasite and carnivores in a restricted ecological niche 'New World'. This might be taken as evidence that carnivores are the 'original' host group for S. neurona. Rather, the capacity of S. neurona to exploit an unusually large number of I.H. species probably indicates that S. neurona maintains non-specificity to its I.H. as an adaptive response to insure the survival of the parasite in areas in which the 'preferred' host is not available. This review concludes with the view that adaptation of S. neurona to a new host is a complex interplay that involves a large number of determinants.
Sarcocystis heydorni, n. sp. (Apicomplexa: Protozoa) with cattle (Bos taurus) and human (Homo sapiens) cycle

USDA-ARS?s Scientific Manuscript database

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 ...
Malabsorption syndrome observed in the common octopus Octopus vulgaris infected with Aggregata octopiana (Protista: Apicomplexa).

PubMed

Gestal, C; Páez de la Cadena, M; Pascual, S

2002-08-15

Octopus vulgaris infected with Aggregata octopiana were collected from an open-water culture system in the Ría of Aldán (NW Spain). Digestive tract infection values were determined with the use of a Neubauer chamber by counting the number of A. octopiana sporocysts. After determining enzyme activity values by the colorimetric Api-Zym system Biomerieux, one representative enzyme of glycosidases, peptid hydrolases and phosphoric hydrolases showing high activity was spectrophotometrically analysed. The enzymes were maltase and leucine-aminopeptidase (LAP) involved in the absorption process, and acid phosphatase, a lysosomic enzyme, respectively. Enzymatic activity of maltase and LAP decreased significantly, with increased sporocyst counts. However, acid phosphatase activity increased with severity of infection, indicating the presence of degradative enzymes from phagocytic cells in the infected area. A detrimental effect on gastrointestinal function may result from a decrease or malfunction of absorption enzymes. The results suggest a malabsorption syndrome resulting from parasitic infection.
Monophyly of the species of Hepatozoon (Adeleorina: Hepatozoidae) parasitizing (African) anurans, with the description of three new species from hyperoliid frogs in South Africa.

PubMed

Netherlands, Edward C; Cook, Courtney A; Du Preez, Louis H; Vanhove, Maarten P M; Brendonck, Luc; Smit, Nico J

2017-12-04

Haemogregarines (Apicomplexa: Adeleiorina) are a diverse group of haemoparasites reported from almost all vertebrate classes. The most commonly recorded haemogregarines to parasitize anurans are species of Hepatozoon Miller, 1908. To date 16 Hepatozoon species have been described from anurans in Africa, with only a single species, Hepatozoon hyperolli (Hoare, 1932), infecting a member of the Hyperoliidae. Furthermore, only two Hepatozoon species are known from South African anurans, namely Hepatozoon theileri (Laveran, 1905) and Hepatozoon ixoxo Netherlands, Cook and Smit, 2014, from Amietia delalandii (syn. Amietia quecketti) and three Sclerophrys species, respectively. Blood samples were collected from a total of 225 individuals representing nine hyperoliid species from several localities throughout northern KwaZulu-Natal, South Africa. Twenty frogs from three species were found positive for haemogregarines, namely Afrixalus fornasinii (6/14), Hyperolius argus (2/39), and Hyperolius marmoratus (12/74). Based on morphological characteristics, morphometrics and molecular findings three new haemogregarine species, Hepatozoon involucrum Netherlands, Cook and Smit n. sp., Hepatozoon tenuis Netherlands, Cook and Smit n. sp. and Hepatozoon thori Netherlands, Cook and Smit n. sp., are described from hyperoliid hosts. Furthermore, molecular analyses show anuran Hepatozoon species to be a separate monophyletic group, with species isolated from African hosts forming a monophyletic clade within this cluster.
Phylogenetic relationship of Hepatozoon blood parasites found in snakes from Africa, America and Asia.

PubMed

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.
Parasites and pathological condition in Green mussel Perna viridis Linnaeus, 1758 from western Johor Straits, Malaysia

NASA Astrophysics Data System (ADS)

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

2018-04-01

This study describes the parasites and pathological condition of infected organ of the green mussel Perna viridis from Merambong Shoal, Western Johor Straits, Malaysia. Samples were collected randomly in November and December 2013. Histopathology techniques using Masson's Trichrome staining protocol were performed and the thin sections were observed under light microscope. Result showed that gonad was the most infected organ followed by the digestive tubule, adductor muscle, intestine and mantle tissue. The parasites (apicomplexa) such as spore-like Nematopsis, macrogamont-like coccidian, mature oocyst-like coccidian, unidentified coccidian and protozoan were found in the adductor muscle, gonad and mantle. Meanwhile, the pathological conditions were found in all infected organs except the gill, such as particular melanin deposits in cytoplasm, Rickettsia-like or Chlamydiae organism and bacteria-like inclusions. Haemocytic infiltrations were found in the surrounding connective tissues of all infected organs. However, these light infections are not causing morbidity and mortalityof the green mussel P.viridis. This study provides baseline information on health profile of the green mussel P.viridis. Further investigations are needed particularly on parasite species identification and their ecology. Understanding of the morphology and pathology of parasites infecting mollusks are very important for management of the resources.
Consistent patterns of high alpha and low beta diversity in tropical parasitic and free-living protists.

PubMed

Lentendu, Guillaume; Mahé, Frédéric; Bass, David; Rueckert, Sonja; Stoeck, Thorsten; Dunthorn, Micah

2018-05-30

Tropical animals and plants are known to have high alpha diversity within forests, but low beta diversity between forests. By contrast, it is unknown whether microbes inhabiting the same ecosystems exhibit similar biogeographic patterns. To evaluate the biogeographies of tropical protists, we used metabarcoding data of species sampled in the soils of three lowland Neotropical rainforests. Taxa-area and distance-decay relationships for three of the dominant protist taxa and their subtaxa were estimated at both the OTU and phylogenetic levels, with presence-absence and abundance-based measures. These estimates were compared to null models. High local alpha and low regional beta diversity patterns were consistently found for both the parasitic Apicomplexa and the largely free-living Cercozoa and Ciliophora. Similar to animals and plants, the protists showed spatial structures between forests at the OTU and phylogenetic levels, and only at the phylogenetic level within forests. These results suggest that the biogeographies of macro- and micro-organismal eukaryotes in lowland Neotropical rainforests are partially structured by the same general processes. However, and unlike the animals and plants, the protist OTUs did not exhibit spatial structures within forests, which hinders our ability to estimate the local and regional diversity of protists in tropical forests. © 2018 John Wiley & Sons Ltd.
[Serological survey of animal toxoplasmosis in Senegal].

PubMed

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.
Actin Filament Polymerization Regulates Gliding Motility by Apicomplexan ParasitesV⃞

PubMed Central

Wetzel, D.M.; Håkansson, S.; Hu, K.; Roos, D.; Sibley, L.D.

2003-01-01

Host cell entry by Toxoplasma gondii depends critically on actin filaments in the parasite, yet paradoxically, its actin is almost exclusively monomeric. In contrast to the absence of stable filaments in conventional samples, rapid-freeze electron microscopy revealed that actin filaments were formed beneath the plasma membrane of gliding parasites. To investigate the role of actin filaments in motility, we treated parasites with the filament-stabilizing drug jasplakinolide (JAS) and monitored the distribution of actin in live and fixed cells using yellow fluorescent protein (YFP)-actin. JAS treatment caused YFP-actin to redistribute to the apical and posterior ends, where filaments formed a spiral pattern subtending the plasma membrane. Although previous studies have suggested that JAS induces rigor, videomicroscopy demonstrated that JAS treatment increased the rate of parasite gliding by approximately threefold, indicating that filaments are rate limiting for motility. However, JAS also frequently reversed the normal direction of motility, disrupting forward migration and cell entry. Consistent with this alteration, subcortical filaments in JAS-treated parasites occurred in tangled plaques as opposed to the straight, roughly parallel orientation observed in control cells. These studies reveal that precisely controlled polymerization of actin filaments imparts the correct timing, duration, and directionality of gliding motility in the Apicomplexa. PMID:12589042
Dynamics of avian haemosporidian assemblages through millennial time scales inferred from insular biotas of the West Indies

PubMed Central

Soares, Leticia; Latta, Steven C.; Ricklefs, Robert E.

2017-01-01

Although introduced hemosporidian (malaria) parasites (Apicomplexa: Haemosporida) have hastened the extinction of endemic bird species in the Hawaiian Islands and perhaps elsewhere, little is known about the temporal dynamics of endemic malaria parasite populations. Haemosporidian parasites do not leave informative fossils, and records of population change are lacking beyond a few decades. Here, we take advantage of the isolation of West Indian land-bridge islands by rising postglacial sea levels to estimate rates of change in hemosporidian parasite assemblages over a millennial time frame. Several pairs of West Indian islands have been connected and separated by falling and rising sea levels associated with the advance and retreat of Pleistocene continental glaciers. We use island isolation following postglacial sea-level rise, ca. 2.5 ka, to characterize long-term change in insular assemblages of hemosporidian parasites. We find that assemblages on formerly connected islands are as differentiated as assemblages on islands that have never been connected, and both are more differentiated than local assemblages sampled up to two decades apart. Differentiation of parasite assemblages between formerly connected islands reflects variation in the prevalence of shared hemosporidian lineages, whereas differentiation between islands isolated by millions of years reflects replacement of hemosporidian lineages infecting similar assemblages of avian host species. PMID:28607060
Dynamics of avian haemosporidian assemblages through millennial time scales inferred from insular biotas of the West Indies.

PubMed

Soares, Leticia; Latta, Steven C; Ricklefs, Robert E

2017-06-20

Although introduced hemosporidian (malaria) parasites (Apicomplexa: Haemosporida) have hastened the extinction of endemic bird species in the Hawaiian Islands and perhaps elsewhere, little is known about the temporal dynamics of endemic malaria parasite populations. Haemosporidian parasites do not leave informative fossils, and records of population change are lacking beyond a few decades. Here, we take advantage of the isolation of West Indian land-bridge islands by rising postglacial sea levels to estimate rates of change in hemosporidian parasite assemblages over a millennial time frame. Several pairs of West Indian islands have been connected and separated by falling and rising sea levels associated with the advance and retreat of Pleistocene continental glaciers. We use island isolation following postglacial sea-level rise, ca. 2.5 ka, to characterize long-term change in insular assemblages of hemosporidian parasites. We find that assemblages on formerly connected islands are as differentiated as assemblages on islands that have never been connected, and both are more differentiated than local assemblages sampled up to two decades apart. Differentiation of parasite assemblages between formerly connected islands reflects variation in the prevalence of shared hemosporidian lineages, whereas differentiation between islands isolated by millions of years reflects replacement of hemosporidian lineages infecting similar assemblages of avian host species.
Targeted Delivery of Toxoplasma gondii Antigens to Dendritic Cells Promote Immunogenicity and Protective Efficiency against Toxoplasmosis

PubMed Central

Lakhrif, Zineb; Moreau, Alexis; Hérault, Bruno; Di-Tommaso, Anne; Juste, Matthieu; Moiré, Nathalie; Dimier-Poisson, Isabelle; Mévélec, Marie-Noëlle; Aubrey, Nicolas

2018-01-01

Toxoplasmosis is a major public health problem and the development of a human vaccine is of high priority. Efficient vaccination against Toxoplasma gondii requires both a mucosal and systemic Th1 immune response. Moreover, dendritic cells play a critical role in orchestrating the innate immune functions and driving specific adaptive immunity to T. gondii. In this study, we explore an original vaccination strategy that combines administration via mucosal and systemic routes of fusion proteins able to target the major T. gondii surface antigen SAG1 to DCs using an antibody fragment single-chain fragment variable (scFv) directed against DEC205 endocytic receptor. Our results show that SAG1 targeting to DCs by scFv via intranasal and subcutaneous administration improved protection against chronic T. gondii infection. A marked reduction in brain parasite burden is observed when compared with the intranasal or the subcutaneous route alone. DC targeting improved both local and systemic humoral and cellular immune responses and potentiated more specifically the Th1 response profile by more efficient production of IFN-γ, interleukin-2, IgG2a, and nasal IgA. This study provides evidence of the potential of DC targeting for the development of new vaccines against a range of Apicomplexa parasites. PMID:29515595
CenH3 evolution reflects meiotic symmetry as predicted by the centromere drive model

PubMed Central

Zedek, František; Bureš, Petr

2016-01-01

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. PMID:27629066
Utility of the cytochrome c oxidase subunit I gene for the diagnosis of toxoplasmosis using PCR.

PubMed

Feng, Xue; Norose, Kazumi; Li, Kexin; Hikosaka, Kenji

2017-10-01

Toxoplasmosis is caused by the protozoan parasite Toxoplasma gondii, which belongs to the phylum Apicomplexa. Since this parasite causes severe clinical symptoms in immunocompromised patients, early diagnosis of toxoplasmosis is essential. PCR is currently used for early diagnosis, but there is no consensus regarding the most effective method for amplifying Toxoplasma DNA. In this study, we considered the utility of the cytochrome c subunit I (cox1) gene, which is encoded in the mitochondrial DNA of this parasite, as a novel target of PCR for the diagnosis of toxoplasmosis. To do this, we compared its copy number per haploid nuclear genome and the detection sensitivity of cox1-PCR with the previously reported target genes B1 and 18S rRNA and the AF146527 repeat element. We found that the copy number of cox1 was high and that the PCR using cox1 primers was more efficient at amplifying Toxoplasma DNA than the other PCR targets examined. In addition, PCR using clinical samples indicated that the cox1 gene would be useful for the diagnosis of toxoplasmosis. These findings suggest that use of cox1-PCR would facilitate the diagnosis of toxoplasmosis in clinical laboratories. Copyright © 2017 Elsevier B.V. All rights reserved.
Protective effect of intranasal immunization with Neospora caninum membrane antigens against murine neosporosis established through the gastrointestinal tract

PubMed Central

Ferreirinha, Pedro; Dias, Joana; Correia, Alexandra; Pérez-Cabezas, Begoña; Santos, Carlos; Teixeira, Luzia; Ribeiro, Adília; Rocha, António; Vilanova, Manuel

2014-01-01

Neospora caninum is an Apicomplexa parasite that in the last two decades was acknowledged as the main pathogenic agent responsible for economic losses in the cattle industry. In the present study, the effectiveness of intranasal immunization with N. caninum membrane antigens plus CpG adjuvant was assessed in a murine model of intragastrically established neosporosis. Immunized mice presented a lower parasitic burden in the brain on infection with 5 × 107 tachyzoites, showing that significant protection was achieved by this immunization strategy. Intestinal IgA antibodies raised by immunization markedly agglutinated live N. caninum tachyzoites whereas previous opsonization with IgG antibodies purified from immunized mice sera reduced parasite survival within macrophage cells. Although an IgG1 : IgG2a ratio < 1 was detected in the immunized mice before and after infection, indicative of a predominant T helper type 1 immune response, no increased production of interferon-γ was detected in the spleen or mesenteric lymph nodes of the immunized mice. Altogether, these results show that mucosal immunization with N. caninum membrane proteins plus CpG adjuvant protect against intragastrically established neosporosis and indicate that parasite-specific mucosal and circulating antibodies have a protective role against this parasitic infection. PMID:24128071

First detection of anti-Besnoitia spp. specific antibodies in horses and donkeys in Italy.

PubMed

Villa, Luca; Gazzonis, Alessia Libera; Álvarez-García, Gema; Diezma-Díaz, Carlos; Zanzani, Sergio Aurelio; Manfredi, Maria Teresa

2018-06-20

Among Apicomplexa protozoa infecting equids, Besnoitia spp., Toxoplasma gondii and Neospora spp. represent important issues from a sanitary and zootechnical viewpoint. However, only scarce epidemiological data are available on the spread of the infections in horses and donkeys in Europe. Therefore, a serosurvey was planned to estimate the prevalence of these Sarcocystidae species in Italian equids. Serum samples from 268 horses and 18 donkeys raised in Italy were collected and serologically analyzed to detect anti-Besnoitia spp., anti-T. gondii and anti-Neospora spp. antibodies: an approach based on an initial screening by in-house ELISA followed by a confirmatory WB was used. Two horses (0.7%) and four donkeys (22.2%), showed antibodies anti-Besnoitia spp. Ten horses (3.7%) resulted positive to T. gondii and one of these (0.4%) was seropositive also to Neospora spp. This is the first detection of anti-Besnoitia spp. specific antibodies in Italian horses and donkeys. The study confirmed the circulation of Besnoitia spp. among equids in Europe. Low prevalence of T. gondii and Neospora spp. in horses raised in Italy was reported. Nevertheless, it is noteworthy to consider that consumption of horse meat could represent a source for human toxoplasmosis. Copyright © 2018. Published by Elsevier B.V.
AMA1-Deficient Toxoplasma gondii Parasites Transiently Colonize Mice and Trigger an Innate Immune Response That Leads to Long-Lasting Protective Immunity

PubMed Central

Lagal, Vanessa; Dinis, Márcia; Cannella, Dominique; Bargieri, Daniel; Gonzalez, Virginie; Andenmatten, Nicole; Meissner, Markus

2015-01-01

The apical membrane antigen 1 (AMA1) protein was believed to be essential for the perpetuation of two Apicomplexa parasite genera, Plasmodium and Toxoplasma, until we genetically engineered viable parasites lacking AMA1. The reduction in invasiveness of the Toxoplasma gondii RH-AMA1 knockout (RH-AMA1KO) tachyzoite population, in vitro, raised key questions about the outcome associated with these tachyzoites once inoculated in the peritoneal cavity of mice. In this study, we used AMNIS technology to simultaneously quantify and image the parasitic process driven by AMA1KO tachyzoites. We report their ability to colonize and multiply in mesothelial cells and in both resident and recruited leukocytes. While the RH-AMA1KO population amplification is rapidly lethal in immunocompromised mice, it is controlled in immunocompetent hosts, where immune cells in combination sense parasites and secrete proinflammatory cytokines. This innate response further leads to a long-lasting status immunoprotective against a secondary challenge by high inocula of the homologous type I or a distinct type II T. gondii genotypes. While AMA1 is definitively not an essential protein for tachyzoite entry and multiplication in host cells, it clearly assists the expansion of parasite population in vivo. PMID:25847964
Two new species of Hepatozoon (Apicomplexa: Hepatozoidae) parasitising species of Philothamnus (Ophidia: Colubridae) from South Africa.

PubMed

Cook, Courtney Antonia; Netherlands, Edward Charles; As, Johann van; Jacobus Smit, Nico

2018-04-03

To date, only a few species of Hepatozoon Miller, 1908 have been described from amphibians and reptiles of South Africa, including two species from anuran hosts, three from saurians, one from chelonians, and two from ophidians. Hepatozoon bitis (Fantham, 1925) and Hepatozoon refringens (Sambon et Seligmann, 1907), parasitising Bitis arientans (Merrem) and Pseudoaspis cana (Linnaeus), respectively, were described in the early 1900s and since then there have been no further species of Hepatozoon described from snakes in South Africa. Blood smears, used in peripheral blood haemogregarine stage morphometrics, and whole blood used in molecular characterisation of haemogregarines were collected from the caudal vein of six snakes of three species, namely Philothamnus hoplogaster (Günther), Philothamnus semivariegatus (Smith) and Philothamnus natalensis natalensis (Smith). For comparison, a comprehensive table summarising available information on species of Hepatozoon from African snakes is presented. Haemogregarines found infecting the snakes from the present study were morphologically and molecularly different from any previously described from Africa and are thus here described as Hepatozoon angeladaviesae sp. n. and Hepatozoon cecilhoarei sp. n. Both haemogregarine species were observed to cause considerable dehaemoglobinisation of the host cell, in case of infection with H. angeladaviesae resulting in a characteristic peripheral undulation of the host cell membrane and karyorrhexis. To the authors' knowledge, these are the first haemogregarines parasitising snakes of the genus Philothamnus Smith described using both morphological and molecular characteristics in Africa.
Parasites and malignancies, a review, with emphasis on digestive cancer induced by Cryptosporidium parvum (Alveolata: Apicomplexa)

PubMed Central

Benamrouz, S.; Conseil, V.; Creusy, C.; Calderon, E.; Dei-Cas, E.; Certad, G.

2012-01-01

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. PMID:22348213
Parasites and malignancies, a review, with emphasis on digestive cancer induced by Cryptosporidium parvum (Alveolata: Apicomplexa).

PubMed

Benamrouz, S; Conseil, V; Creusy, C; Calderon, E; Dei-Cas, E; Certad, G

2012-05-01

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.
A description of Isospora amphiboluri (Apicomplexa: Eimeriidae) from the inland bearded dragon, Pogona vitticeps (Sauria: Agamidae).

PubMed

McAllister, C T; Upton, S J; Jacobson, E R; Kopit, W

1995-04-01

Fecal samples from 50 captive inland bearded dragons, Pogona vitticeps (Ahl, 1926), bred in California, were examined for coccidian parasites. Sixteen (32%) of the lizards were found to be passing oocysts of Isospora amphiboluri Cannon, 1967, previously described from bearded dragons Pogona barbata (Cuvier, 1829) from Australia. Sporulated oocytes were spherical to subspherical, 25.3 x 25.1 (23-26 x 23-26) microns, with a shape index (length/width) of 1.0 (1.0-1.1). A micropyle, oocyst residuum, and polar granule were absent. Sporocyts were ovoidal, 17.0 x 11.4 (16-18 x 11-12) microns, with a shape index of 1.5 (1.4-1.7). A sporocyst residuum, Stieda, and substieda bodies were present, but parastieda bodies were absent. Sporozoites were elongated, 13.9 x 3.5 (12-15 x 3-4) microns in situ, containing spherical anterior and posterior refractile bodies. The occurrence of I. amphiboluri in P. vitticeps is a new host and geographic record for the parasite. Photomicrographs of the oocysts and endogenous life cycle stages of I. amphiboluri are presented for the first time.
[Experimental transmission of Cryptosporidium baileyi (Apicomplexa: Cryptosporidiidae) isolated of broiler chicken to Japanese quail (Coturnix japonica)].

PubMed

Cardozo, Sergian V; Teixeira Filho, Walter L; Lopes, Carlos Wilson G

2005-01-01

In this work, oocysts of Cryptosporidium baileyi were isolated and identified in broiler chickens from three different Municipalities of the State of Rio de Janeiro, where they were isolated and identified by using the centrifuge- flotation technique associated to bright-field. Staining techniques, such as: modified Ziehl-Neelsen and safranin-methylene blue, were carried out to confirm natural infection. Oocysts of C. baileyi from broiler chickens were able to infect Coccidia-free Japanese quails, by observation of endogenous stages at histological sections, and the elimination of oocysts in the feces with prepatent period of seven days and patent period of 21 days after infection. Oocysts of C. baileyi from broiler chickens and Japanese quails were similar on bright-field microscopy. With respect to the staining techniques used in this research, all of them left to significant changes in length and width of oocysts, but shape indexes were maintained. Bright-field microscopy was the best technique for oocysts comparison shed by broiler chickens and Japanese quail because of no different among oocysts were observed.
Sarcocystis arctica (Apicomplexa: Sarcocystidae): ultrastructural description and its new host record, the Alaskan wolf (Canis lupus).

PubMed

Calero-Bernal, Rafael; Cerqueira-Cézar, Camila K; Verma, Shiv Kumar; Mowery, Joseph; Carmena, David; Beckmen, Kimberlee; Dubey, Jitender P

2016-07-01

Sarcocystis sarcocysts are common in muscles of herbivores but are rare in muscles of carnivores. Here, we report sarcocysts in the muscles of a gray wolf (Canis lupus) from Alaska, USA, for the first time. Sarcocysts extracted from the tongue of the wolf were up to 900 μm long and slender and appeared to have a relatively thin wall by light microscope. By transmission electron microscopy, the sarcocyst wall most closely resembled "type 9c," and had a wavy parasitophorous vacuolar membrane folded as pleomorphic villar protrusions (vp), with anastomoses of tips. The vp and the ground substance (gs) layer were smooth without tubules or granules. The gs was up to 2.0 μm thick. The total width of the wall including vp and the gs was 3.5 μm. The vp were up to 1.5 μm long. Mature sarcocysts contained numerous bradyzoites and few metrocytes. The bradyzoites were 9.5 μm long and 1.5 μm wide, and contained all organelles found in Sarcocystis bradyzoites with at least two rhoptries. Molecular characterization showed the highest identity for 18S rRNA, 28S rRNA, ITS-1, and cox1 sequences of Sarcocystis arctica of the Arctic fox (Vulpes lagopus) from Norway. The ultrastructure of S. arctica from the fox is unknown. Here, we provide ultrastructure of S. arctica from the Alaskan wolf for the first time. The definitive host of S. arctica remains unknown.
Identification of a Novel Renal Coccidian (Apicomplexa: Eimeriidae) from the Great-Horned Owl ( Bubo virginianus ), USA.

PubMed

Jankovsky, Jennie M; Brand, Mabre; Gerhold, Richard W

2017-04-01

We diagnosed renal coccidiosis in two of five Great-horned Owls ( Bubo virginianus ) examined in eastern Tennessee, US, 2007-13. Histopathologic examination of the kidneys revealed multifocal mild-to-moderate dilation and epithelial hyperplasia of collecting ducts. Renal collecting duct epithelial cells contained intracytoplasmic microgametocytes, macrogametocytes, and sporulating and sporulated oocysts. Renal coccidiosis in affected birds did not result in significant inflammation. Sequence analysis of the amplified partial 18S short subunit ribosomal RNA coding region from examination of formalin fixed tissue by using PCR disclosed a 93% identity to Eimeria reichenowi in GenBank, suggesting a novel Eimeria sp.
Sarcocystis arctica (Apicomplexa: Sarcocystidae): ultrastructural description and its new host record, the Alaskan wolf (Canis lupus

USDA-ARS?s Scientific Manuscript database

Sarcocystis sarcocysts are common in muscles of herbivores but are rare in muscles of carnivores. Here, we report sarcocysts in muscle of an Alaskan wolf (Canis lupus) from Alaska, USA for the first time. Sarcocysts extracted from tongue of the wolf were up to 900 µm long, slender, and appeared to h...
Potential effects of the United States-Mexico border fence on wildlife.

PubMed

Flesch, Aaron D; Epps, Clinton W; Cain, James W; Clark, Matt; Krausman, Paul R; Morgart, John R

2010-02-01

Security infrastructure along international boundaries threatens to degrade connectivity for wildlife. To explore potential effects of a fence under construction along the U.S.-Mexico border on wildlife, we assessed movement behavior of two species with different life histories whose regional persistence may depend on transboundary movements. We used radiotelemetry to assess how vegetation and landscape structure affect flight and natal dispersal behaviors of Ferruginous Pygmy-Owls (Glaucidium brasilianum), and satellite telemetry, gene-flow estimates, and least-cost path models to assess movement behavior and interpopulation connectivity of desert bighorn sheep (Ovis canadensis mexicana). Flight height of Pygmy-Owls averaged only 1.4 m (SE 0.1) above ground, and only 23% of flights exceeded 4 m. Juvenile Pygmy-Owls dispersed at slower speeds, changed direction more, and had lower colonization success in landscapes with larger vegetation openings or higher levels of disturbance (p < or = 0.047), which suggests large vegetation gaps coupled with tall fences may limit transboundary movements. Female bighorn sheep crossed valleys up to 4.9 km wide, and microsatellite analyses indicated relatively high levels of gene flow and migration (95% CI for F(ST)=0.010-0.115, Nm = 1.9-24.8, M =10.4-15.4) between populations divided by an 11-km valley. Models of gene flow based on regional topography and movement barriers suggested that nine populations of bighorn sheep in northwestern Sonora are linked by dispersal with those in neighboring Arizona. Disruption of transboundary movement corridors by impermeable fencing would isolate some populations on the Arizona side. Connectivity for other species with similar movement abilities and spatial distributions may be affected by border development, yet mitigation strategies could address needs of wildlife and humans.
Spatial, Temporal, and Density-Dependent Components of Habitat Quality for a Desert Owl

PubMed Central

Flesch, Aaron D.; Hutto, Richard L.; van Leeuwen, Willem J. D.; Hartfield, Kyle; Jacobs, Sky

2015-01-01

Spatial variation in resources is a fundamental driver of habitat quality but the realized value of resources at any point in space may depend on the effects of conspecifics and stochastic factors, such as weather, which vary through time. We evaluated the relative and combined effects of habitat resources, weather, and conspecifics on habitat quality for ferruginous pygmy-owls (Glaucidium brasilianum) in the Sonoran Desert of northwest Mexico by monitoring reproductive output and conspecific abundance over 10 years in and around 107 territory patches. Variation in reproductive output was much greater across space than time, and although habitat resources explained a much greater proportion of that variation (0.70) than weather (0.17) or conspecifics (0.13), evidence for interactions among each of these components of the environment was strong. Relative to habitat that was persistently low in quality, high-quality habitat buffered the negative effects of conspecifics and amplified the benefits of favorable weather, but did not buffer the disadvantages of harsh weather. Moreover, the positive effects of favorable weather at low conspecific densities were offset by intraspecific competition at high densities. Although realized habitat quality declined with increasing conspecific density suggesting interference mechanisms associated with an Ideal Free Distribution, broad spatial heterogeneity in habitat quality persisted. Factors linked to food resources had positive effects on reproductive output but only where nest cavities were sufficiently abundant to mitigate the negative effects of heterospecific enemies. Annual precipitation and brooding-season temperature had strong multiplicative effects on reproductive output, which declined at increasing rates as drought and temperature increased, reflecting conditions predicted to become more frequent with climate change. Because the collective environment influences habitat quality in complex ways, integrated approaches
Spatial, temporal, and density-dependent components of habitat quality for a desert owl.

PubMed

Flesch, Aaron D; Hutto, Richard L; van Leeuwen, Willem J D; Hartfield, Kyle; Jacobs, Sky

2015-01-01

Spatial variation in resources is a fundamental driver of habitat quality but the realized value of resources at any point in space may depend on the effects of conspecifics and stochastic factors, such as weather, which vary through time. We evaluated the relative and combined effects of habitat resources, weather, and conspecifics on habitat quality for ferruginous pygmy-owls (Glaucidium brasilianum) in the Sonoran Desert of northwest Mexico by monitoring reproductive output and conspecific abundance over 10 years in and around 107 territory patches. Variation in reproductive output was much greater across space than time, and although habitat resources explained a much greater proportion of that variation (0.70) than weather (0.17) or conspecifics (0.13), evidence for interactions among each of these components of the environment was strong. Relative to habitat that was persistently low in quality, high-quality habitat buffered the negative effects of conspecifics and amplified the benefits of favorable weather, but did not buffer the disadvantages of harsh weather. Moreover, the positive effects of favorable weather at low conspecific densities were offset by intraspecific competition at high densities. Although realized habitat quality declined with increasing conspecific density suggesting interference mechanisms associated with an Ideal Free Distribution, broad spatial heterogeneity in habitat quality persisted. Factors linked to food resources had positive effects on reproductive output but only where nest cavities were sufficiently abundant to mitigate the negative effects of heterospecific enemies. Annual precipitation and brooding-season temperature had strong multiplicative effects on reproductive output, which declined at increasing rates as drought and temperature increased, reflecting conditions predicted to become more frequent with climate change. Because the collective environment influences habitat quality in complex ways, integrated approaches
Redescription and molecular diagnosis of Hepatozoon theileri (Laveran, 1905) (Apicomplexa: Adeleorina: Hepatozoidae), infecting Amietia quecketti (Anura: Pyxicephalidae).

PubMed

Netherlands, Edward C; Cook, Courtney A; Smit, Nico J; du Preez, Louis H

2014-08-01

Blood smears prepared from the peripheral blood of 20 wild caught Amietia quecketti (Boulenger) from the North-West University Botanical Gardens, North West Province, South Africa, were examined for the presence of haemogregarines. A haemogregarine species comparative in morphology, host and geographical locality to that of Haemogregarina theileri Laveran, 1905 was detected. The original description of H. theileri was based solely on frog peripheral blood gamont stages. Later, further parasite stages, including trophozoites and merogonic liver stages, were recorded in a related Amietia sp. from equatorial Africa. This species was originally classified as a member of the genus Haemogregarina Danilewsky, 1885, but due to the close life cycle and morphological resemblance to those of Hepatozoon species, H. theileri was later transferred from Haemogregarina to Hepatozoon Miller, 1908. In the present study, meront and merozoite stages not described before, along with previously observed trophozoite, immature and mature gamont stages, are described from the peripheral blood of hosts. In addition, comparative phylogenetic analysis of the partial 18S rDNA sequence of Hepatozoon theileri to those of other haemogregarine species, including those of species of Hepatozoon and a Haemogregarina, support the taxonomic transfer of H. theileri to Hepatozoon, nesting H. theileri within a clade comprising species parasitising other amphibians. This is the first molecular and phylogenetic analysis of an African anuran species of Hepatozoon.
Two new Eimeria species (Apicomplexa: Eimeriidae) from the yellow-crowned Amazon Amazona ochrocephala (Aves: Psittacidae) in Brazil.

PubMed

Hofstatter, P G; Kawazoe, U

2011-06-01

In this study, we describe 2 new species of Eimeria associated with the yellow-crowned Amazon Amazona ochrocephala. Eimeria amazonae n. sp. has bilayered, ellipsoidal, and smooth oocysts that measure 48.9 × 36.2 µm; the length/width ratio is 1.35. The micropyle and oocyst residuum are both absent, but the polar granule is present. Ovoidal sporocysts are 22.2 × 11.9 µm. Stieda and sub-Stieda bodies and sporocyst residuum are present. The 2 elongate sporozoites are curved and measure 18.1 × 3.4 µm; both have 2 refractile bodies. Eimeria ochrocephalae n. sp. has bilayered, ellipsoidal, and smooth oocysts that measure 43.8 × 27.7 µm; the length/width ratio is 1.58. The micropyle and oocyst residuum are absent, but the polar granule is present; ovoidal sporocysts are 20.6 × 10.1 µm. Stieda and sub-Stieda bodies and sporocyst residuum are present; 2 elongate and curved sporozoites are 15.8 × 3.4 µm, each of which has 2 refractile bodies.
Detection and Molecular Identification of Sarcocystis rileyi (Apicomplexa: Sarcocystidae) From a Northern Shoveler (Anas clypeata) in Mexico.

PubMed

Padilla-Aguilar, Patricia; Romero-Callejas, Evangelina; Osorio-Sarabia, David; Ramírez-Lezama, José; Cigarroa-Toledo, Nohemi; Machain-Williams, Carlos; Manterola, Carlos; Zarza, Heliot

2016-10-01

We detected macroscopic Sarcocystis cysts in a Northern Shoveler ( Anas clypeata ) in the Lerma Marshes, State of Mexico, Mexico in February 2014. The 5.0×2.0-mm macrocysts in the breast muscle of the duck were ovoid and yellow. Using an optical microscope, we saw parasitic forms of a Sarcocystis sp. among muscular fibers; the cysts measured 3.5×1.1 mm. The external wall had a smooth surface and the internal wall had a spongy texture. We identified the macrocysts as Sarcocystis rileyi according to sequences of the 18S rRNA gene, 28S rRNA gene, and ITS-1 region. Sarcocystosis should be considered in similar assessments in wild waterfowl in Mexico. Awareness of S. rileyi among anatids in the Lerma Marshes will contribute to more-effective conservation and management actions.
A NEW SPECIES OF EIMERIA (APICOMPLEXA: EIMERIIDAE) FROM THE EASTERN PIPISTRELLE, PERIMYOTIS SUBFLAVUS (CHIROPTERA: VESPERTILIONIDAE), IN ARKANSAS

PubMed Central

McAllister, Chris T.; Burt, Scott; Seville, R. Scott; Robison, Henry W.

2011-01-01

During November 2009 and March 2010, 20 adult eastern pipistrelles, Perimyotis (=Pipistrellus) subflavus were collected from Polk County, Arkansas, and their feces examined for coccidian parasites. Two (10%) of the bats were found to be passing oocysts of an undescribed species of Eimeria. Oocysts of Eimeria heidti n. sp. were ovoidal to ellipsoidal, 26.1 × 20.5 (23-31 × 18-23) μm, with a bilayered wall, externally rough, internally smooth, and with a shape index of 1.3. Micropyle and oocyst residuum were absent, but a subspherical polar granule was often present. Sporocysts were ovoidal, 13.0 × 8.8 (11-15 × 7-13) μm, the shape index was 1.6, a Stieda body was present and sub-Stieda and para-Stieda bodies were absent. A sporocyst residuum consisting of multiple globules dispersed along the perimeter of the sporocyst and between the sporozoites were present, sporozoites were elongate, with a subspherical anterior refractile body and elongate posterior refractile body; a nucleus not discernable. This is the second coccidian reported from this host and the fourth instance of a coccidian species reported from an Arkansas bat. PMID:21506799
A NEW SPECIES OF EIMERIA (APICOMPLEXA: EIMERIIDAE) FROM THE NORTHERN MYOTIS, MYOTIS SEPTENTRIONALIS (CHIROPTERA: VESPERTILIONIDAE), IN OKLAHOMA

PubMed Central

McAllister, Chris T.; Seville, R. Scott; Roehrs, Zachary P.

2012-01-01

During September 2004, 4 adult northern myotis, Myotis septentrionalis, were collected from LeFlore County, Oklahoma (n = 2), and Logan (n = 1) and Yell (n = 1) counties, Arkansas, and their feces examined for coccidian parasites. Three of 4 bats (75%) were passing oocysts of Eimeria spp. Oocysts of Eimeria tumlisoni n. sp. were ovoidal, 17.6 × 16.8 (16–19 × 14–18) μm with a shape index of 1.0 (1.0–1.1). A micropyle and oocyst residuum were absent, although 1–2 bilobed polar granules were often present. Sporocysts were ovoidal, 10.5 × 5.9 (9–12 × 5–7) μm with a shape index of 1.8 (1.6–2.0). A Stieda body was present, but sub–Stieda and para–Stieda bodies were absent. A sporocyst residuum was present consisting of compact to dispersed granules between the sporozoites. The sporozoites were elongate, with subspherical anterior refractile body and spherical posterior refractile body; a nucleus was not discernable. This is the second coccidian reported from this host and the first instance of a bat coccidian reported from Oklahoma. We also document a new geographic record for Eimeria catronensis in Oklahoma, and provide an emended description. PMID:22509940
Morphological and molecular characterization of Eimeria haematodi, coccidian parasite (Apicomplexa: Eimeriidae) in a rainbow lorikeet (Trichoglossus haematodus).

PubMed

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. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.
Observation on Nematocystis kailashi sp. nov. (Apicomplexa: Eugregarinida) from an Indian earthworm Glyphidrilus tuberosus Stephenson (Annelida: Oligochaeta)

PubMed

Mallik, Partha; Bandyopadhyay, Prabir K

Surveys on aseptate gregarines in earthworm hosts in different districts of West Bengal state of India revealed the existence of one new species of aseptate gregarine of the genus Nematocystis Hesse, 1909 have been identified from the seminal vesicles of the earthworm, Glyphidrilus tuberosus Stephenson, 1916 in the district of Purba Midnapur, West Bengal of India. Gamonts of the organism are very much elongated, cylindrical, nematoid and without mucron. The terminal end adjacent to the nucleus rounded and the distal end pointed. The gamonts measure 846.45-1031.13 (931.86±70.48) μm in length and 18.40-20.45 (19.43±1.05) μm in width. Nucleus elongated or depressed elliptoid, measures 53.17-63.39 (60.33±3.28) μm in length and 13.29-16.36 (14.15±0.89) μm in width. The gametocysts are slightly ovoid, measuring 110.43-120.65 (114.31±3.44) μm in diameter. Oocysts navicular and measure 9.24-10.39 (9.78±0.40) μm×5.77-6.16 (6.04±0.18) μm. Based on critical analysis and comparison with earlier reported species, the species under discussion established as new one.

Observation on Monocystis kuidongae sp. nov. (Apicomplexa: Eugregarinida) from an Indian earthworm Perionyx excavatus Perrier (Annelida: Oligochaeta).

PubMed

Mallik, Partha; Bandyopadhyay, Probir K

2017-06-01

A survey to know the diversity of endoparasitic protozoan parasites of the earthworms of West Bengal, revealed a new species of the genus Monocystis Stein, 1848, that resides in the seminal vesicle of the earthworm Perionyx excavatus Perrier. Monocystis kuidongae sp. nov. is characterized by ovoidal gamonts (trophozoites) with inconspicuous mucron and measure 69.53-102.25 (86.29 ± 11.48) μm × 24.54-61.35 (35.17 ± 12.82) μm. Shape of the gametocysts are almost rounded and measure 81.80-110.43 (96.11 ± 8.85) μm in diameter. Oocysts are navicular with pointed ends and measure 11.55-12.32 (11.78 ± 0.36) µm × 5.00-5.77 (5.39 ± 0.25) µm.
Margolisiella islandica sp. nov. (Apicomplexa: Eimeridae) infecting Iceland scallop Chlamys islandica (Müller, 1776) in Icelandic waters.

PubMed

Kristmundsson, Árni; Helgason, Sigurður; Bambir, Slavko H; Eydal, Matthías; Freeman, Mark A

2011-11-01

Wild Iceland scallops Chlamys islandica from an Icelandic bay were examined for parasites. Queen scallops Aequipecten opercularis from the Faroe Islands and king scallops Pecten maximus and queen scallops from Scottish waters were also examined. Observations revealed heavy infections of eimeriorine parasites in 95-100% of C. islandica but not the other scallop species. All life stages in the apicomplexan reproduction phases, i.e. merogony, gametogony and sporogony, were present. Trophozoites and meronts were common within endothelial cells of the heart's auricle and two generations of free merozoites were frequently seen in great numbers in the haemolymph. Gamonts at various developmental stages were also abundant, most frequently free in the haemolymph. Macrogamonts were much more numerous than microgamonts. Oocysts were exclusively in the haemolymph; live mature oocysts contained numerous (>500) densely packed pairs of sporozoites forming sporocysts. Analysis of the 18S ribosomal DNA revealed that the parasite from C. islandica is most similar (97.7% identity) to an unidentified apicomplexan isolated from the haemolymph of the giant clam, Tridacna crocea, from Japan. Phylogenetic analyses showed that the novel sequence consistently grouped with the Tridacna sequence which formed a robust sister clade to the rhytidocystid group. We propose the name Margolisiella islandica sp. nov., referring to both type host and type locality. Copyright © 2011 Elsevier Inc. All rights reserved.
Metatranscriptomic census of active protists in soils.

PubMed

Geisen, Stefan; Tveit, Alexander T; Clark, Ian M; Richter, Andreas; Svenning, Mette M; Bonkowski, Michael; Urich, Tim

2015-10-01

The high numbers and diversity of protists in soil systems have long been presumed, but their true diversity and community composition have remained largely concealed. Traditional cultivation-based methods miss a majority of taxa, whereas molecular barcoding approaches employing PCR introduce significant biases in reported community composition of soil protists. Here, we applied a metatranscriptomic approach to assess the protist community in 12 mineral and organic soil samples from different vegetation types and climatic zones using small subunit ribosomal RNA transcripts as marker. We detected a broad diversity of soil protists spanning across all known eukaryotic supergroups and revealed a strikingly different community composition than shown before. Protist communities differed strongly between sites, with Rhizaria and Amoebozoa dominating in forest and grassland soils, while Alveolata were most abundant in peat soils. The Amoebozoa were comprised of Tubulinea, followed with decreasing abundance by Discosea, Variosea and Mycetozoa. Transcripts of Oomycetes, Apicomplexa and Ichthyosporea suggest soil as reservoir of parasitic protist taxa. Further, Foraminifera and Choanoflagellida were ubiquitously detected, showing that these typically marine and freshwater protists are autochthonous members of the soil microbiota. To the best of our knowledge, this metatranscriptomic study provides the most comprehensive picture of active protist communities in soils to date, which is essential to target the ecological roles of protists in the complex soil system.
Metatranscriptomic census of active protists in soils

PubMed Central

Geisen, Stefan; Tveit, Alexander T; Clark, Ian M; Richter, Andreas; Svenning, Mette M; Bonkowski, Michael; Urich, Tim

2015-01-01

The high numbers and diversity of protists in soil systems have long been presumed, but their true diversity and community composition have remained largely concealed. Traditional cultivation-based methods miss a majority of taxa, whereas molecular barcoding approaches employing PCR introduce significant biases in reported community composition of soil protists. Here, we applied a metatranscriptomic approach to assess the protist community in 12 mineral and organic soil samples from different vegetation types and climatic zones using small subunit ribosomal RNA transcripts as marker. We detected a broad diversity of soil protists spanning across all known eukaryotic supergroups and revealed a strikingly different community composition than shown before. Protist communities differed strongly between sites, with Rhizaria and Amoebozoa dominating in forest and grassland soils, while Alveolata were most abundant in peat soils. The Amoebozoa were comprised of Tubulinea, followed with decreasing abundance by Discosea, Variosea and Mycetozoa. Transcripts of Oomycetes, Apicomplexa and Ichthyosporea suggest soil as reservoir of parasitic protist taxa. Further, Foraminifera and Choanoflagellida were ubiquitously detected, showing that these typically marine and freshwater protists are autochthonous members of the soil microbiota. To the best of our knowledge, this metatranscriptomic study provides the most comprehensive picture of active protist communities in soils to date, which is essential to target the ecological roles of protists in the complex soil system. PMID:25822483
Toxoplasma gondii Relies on Both Host and Parasite Isoprenoids and Can Be Rendered Sensitive to Atorvastatin

PubMed Central

Li, Zhu-Hong; Ramakrishnan, Srinivasan; Striepen, Boris; Moreno, Silvia N. J.

2013-01-01

Intracellular pathogens have complex metabolic interactions with their host cells to ensure a steady supply of energy and anabolic building blocks for rapid growth. Here we use the obligate intracellular parasite Toxoplasma gondii to probe this interaction for isoprenoids, abundant lipidic compounds essential to many cellular processes including signaling, trafficking, energy metabolism, and protein translation. Synthesis of precursors for isoprenoids in Apicomplexa occurs in the apicoplast and is essential. To synthesize longer isoprenoids from these precursors, T. gondii expresses a bifunctional farnesyl diphosphate/geranylgeranyl diphosphate synthase (TgFPPS). In this work we construct and characterize T. gondii null mutants for this enzyme. Surprisingly, these mutants have only a mild growth phenotype and an isoprenoid composition similar to wild type parasites. However, when extracellular, the loss of the enzyme becomes phenotypically apparent. This strongly suggests that intracellular parasite salvage FPP and/or geranylgeranyl diphosphate (GGPP) from the host. We test this hypothesis using inhibitors of host cell isoprenoid synthesis. Mammals use the mevalonate pathway, which is susceptible to statins. We document strong synergy between statin treatment and pharmacological or genetic interference with the parasite isoprenoid pathway. Mice can be cured with atorvastatin (Lipitor) from a lethal infection with the TgFPPs mutant. We propose a double-hit strategy combining inhibitors of host and parasite pathways as a novel therapeutic approach against Apicomplexan parasites. PMID:24146616
Haemosporidian infection in captive masked bobwhite quail (Colinus virginianus ridgwayi), an endangered subspecies of the northern bobwhite quail.

PubMed

Pacheco, M Andreína; Escalante, Ananias A; Garner, Michael M; Bradley, Gregory A; Aguilar, Roberto F

2011-12-15

The avian haemosporidian parasites (phylum Apicomplexa) are taxonomically diverse and cosmopolitan in distribution; infecting most bird families. Sources of concern are reports of clinical haemosporidian infections in birds kept as part of zoo and aviary collections. Recently, severe and acute mortality episodes have been reported in masked bobwhite quail (Colinus virginianus ridgwayi), an endangered subspecies from the American Southwest. Two hundred and five eggs of the captive flock held in Arivaca, Arizona, were hatched at a zoo in the American Southwest. Thirty-four sub-adult or adult animals had lesions associated with tissue phases of haemoparasites, especially vasculitis, ventricular leiomyositis and ulcerative pododermatitis. Molecular techniques applied to blood collected from the zoo's last twelve remaining animals resulted in the detection of a Plasmodium juxtanucleare-like and Haemoproteus sp. parasites. A Raven (Corvus corax), in a contiguous exhibit, was positive for the same P. juxtanucleare-like parasite, but remained asymptomatic for three years following detection. These findings indicate that other birds in the exhibit within the zoo premises could act as reservoirs. We conclude that haemosporidian infections could be a factor in the demise of the captive masked bobwhite quails housed at the zoo. We suggest that active surveillance for haemoporidian parasites should be incorporated as a precaution to ex situ conservation efforts of susceptible endangered species. Copyright © 2011 Elsevier B.V. All rights reserved.
The search for the missing link: a relic plastid in Perkinsus?

PubMed

Fernández Robledo, José A; Caler, Elisabet; Matsuzaki, Motomichi; Keeling, Patrick J; Shanmugam, Dhanasekaran; Roos, David S; Vasta, Gerardo R

2011-10-01

Perkinsus marinus (Phylum Perkinsozoa) is a protozoan parasite that has devastated natural and farmed oyster populations in the USA, significantly affecting the shellfish industry and the estuarine environment. The other two genera in the phylum, Parvilucifera and Rastrimonas, are parasites of microeukaryotes. The Perkinsozoa occupies a key position at the base of the dinoflagellate branch, close to its divergence from the Apicomplexa, a clade that includes parasitic protista, many harbouring a relic plastid. Thus, as a taxon that has also evolved toward parasitism, the Perkinsozoa has attracted the attention of biologists interested in the evolution of this organelle, both in its ultrastructure and the conservation, loss or transfer of its genes. A review of the recent literature reveals mounting evidence in support of the presence of a relic plastid in P. marinus, including the presence of multimembrane structures, characteristic metabolic pathways and proteins with a bipartite N-terminal extension. Further, these findings raise intriguing questions regarding the potential functions and unique adaptation of the putative plastid and/or plastid genes in the Perkinsozoa. In this review we analyse the above-mentioned evidence and evaluate the potential future directions and expected benefits of addressing such questions. Given the rapidly expanding molecular/genetic resources and methodological toolbox for Perkinsus spp., these organisms should complement the currently established models for investigating plastid evolution within the Chromalveolata. Copyright © 2011. Published by Elsevier Ltd.
Purine salvage in the apicomplexan Sarcocystis neurona, and generation of hypoxanthine-xanthine-guanine phosphoribosyltransferase-deficient clones for positive-negative selection of transgenic parasites.

PubMed

Dangoudoubiyam, Sriveny; Zhang, Zijing; Howe, Daniel K

2014-09-01

Sarcocystis neurona is an apicomplexan parasite that causes severe neurological disease in horses and marine mammals. The Apicomplexa are all obligate intracellular parasites that lack purine biosynthesis pathways and rely on the host cell for their purine requirements. Hypoxanthine-xanthine-guanine phosphoribosyltransferase (HXGPRT) and adenosine kinase (AK) are key enzymes that function in two complementary purine salvage pathways in apicomplexans. Bioinformatic searches of the S. neurona genome revealed genes encoding HXGPRT, AK and all of the major purine salvage enzymes except purine nucleoside phosphorylase. Wild-type S. neurona were able to grow in the presence of mycophenolic acid (MPA) but were inhibited by 6-thioxanthine (6-TX), suggesting that the pathways involving either HXGPRT or AK are functional in this parasite. Prior work with Toxoplasma gondii demonstrated the utility of HXGPRT as a positive-negative selection marker. To enable the use of HXGPRT in S. neurona, the SnHXGPRT gene sequence was determined and a gene-targeting plasmid was transfected into S. neurona. SnHXGPRT-deficient mutants were selected with 6-TX, and single-cell clones were obtained. These Sn∆HXG parasites were susceptible to MPA and could be complemented using the heterologous T. gondii HXGPRT gene. In summary, S. neurona possesses both purine salvage pathways described in apicomplexans, thus allowing the use of HXGPRT as a positive-negative drug selection marker in this parasite.
Global Analysis of Apicomplexan Protein S-Acyl Transferases Reveals an Enzyme Essential for Invasion

PubMed Central

Frénal, Karine; Tay, Chwen L; Mueller, Christina; Bushell, Ellen S; Jia, Yonggen; Graindorge, Arnault; Billker, Oliver; Rayner, Julian C; Soldati-Favre, Dominique

2013-01-01

The advent of techniques to study palmitoylation on a whole proteome scale has revealed that it is an important reversible modification that plays a role in regulating multiple biological processes. Palmitoylation can control the affinity of a protein for lipid membranes, which allows it to impact protein trafficking, stability, folding, signalling and interactions. The publication of the palmitome of the schizont stage of Plasmodium falciparum implicated a role for palmitoylation in host cell invasion, protein export and organelle biogenesis. However, nothing is known so far about the repertoire of protein S-acyl transferases (PATs) that catalyse this modification in Apicomplexa. We undertook a comprehensive analysis of the repertoire of Asp-His-His-Cys cysteine-rich domain (DHHC-CRD) PAT family in Toxoplasma gondii and Plasmodium berghei by assessing their localization and essentiality. Unlike functional redundancies reported in other eukaryotes, some apicomplexan-specific DHHCs are essential for parasite growth, and several are targeted to organelles unique to this phylum. Of particular interest is DHHC7, which localizes to rhoptry organelles in all parasites tested, including the major human pathogen P. falciparum. TgDHHC7 interferes with the localization of the rhoptry palmitoylated protein TgARO and affects the apical positioning of the rhoptry organelles. This PAT has a major impact on T. gondii host cell invasion, but not on the parasite’s ability to egress. PMID:23638681
A serine–arginine-rich (SR) splicing factor modulates alternative splicing of over a thousand genes in Toxoplasma gondii

PubMed Central

Yeoh, Lee M.; Goodman, Christopher D.; Hall, Nathan E.; van Dooren, Giel G.; McFadden, Geoffrey I.; Ralph, Stuart A.

2015-01-01

Single genes are often subject to alternative splicing, which generates alternative mature mRNAs. This phenomenon is widespread in animals, and observed in over 90% of human genes. Recent data suggest it may also be common in Apicomplexa. These parasites have small genomes, and economy of DNA is evolutionarily favoured in this phylum. We investigated the mechanism of alternative splicing in Toxoplasma gondii, and have identified and localized TgSR3, a homologue of ASF/SF2 (alternative-splicing factor/splicing factor 2, a serine-arginine–rich, or SR protein) to a subnuclear compartment. In addition, we conditionally overexpressed this protein, which was deleterious to growth. qRT-PCR was used to confirm perturbation of splicing in a known alternatively-spliced gene. We performed high-throughput RNA-seq to determine the extent of splicing modulated by this protein. Current RNA-seq algorithms are poorly suited to compact parasite genomes, and hence we complemented existing tools by writing a new program, GeneGuillotine, that addresses this deficiency by segregating overlapping reads into distinct genes. In order to identify the extent of alternative splicing, we released another program, JunctionJuror, that detects changes in intron junctions. Using this program, we identified about 2000 genes that were constitutively alternatively spliced in T. gondii. Overexpressing the splice regulator TgSR3 perturbed alternative splicing in over 1000 genes. PMID:25870410
Screening for small molecule inhibitors of Toxoplasma gondii.

PubMed

Kortagere, Sandhya

2012-12-01

Toxoplasma gondii, the agent that causes toxoplasmosis, is an opportunistic parasite that infects many mammalian species. It is an obligate intracellular parasite that causes severe congenital neurological and ocular disease mostly in immunocompromised humans. The current regimen of therapy includes only a few medications that often lead to hypersensitivity and toxicity. In addition, there are no vaccines available to prevent the transmission of this agent. Therefore, safer and more effective medicines to treat toxoplasmosis are urgently needed. The author presents in silico and in vitro strategies that are currently used to screen for novel targets and unique chemotypes against T. gondii. Furthermore, this review highlights the screening technologies and characterization of some novel targets and new chemical entities that could be developed into highly efficacious treatments for toxoplasmosis. A number of diverse methods are being used to design inhibitors against T. gondii. These include ligand-based methods, in which drugs that have been shown to be efficacious against other Apicomplexa parasites can be repurposed to identify lead molecules against T. gondii. In addition, structure-based methods use currently available repertoire of structural information in various databases to rationally design small-molecule inhibitors of T. gondii. Whereas the screening methods have their advantages and limitations, a combination of methods is ideally suited to design small-molecule inhibitors of complex parasites such as T. gondii.
Toxoplasma gondii relies on both host and parasite isoprenoids and can be rendered sensitive to atorvastatin.

PubMed

Li, Zhu-Hong; Ramakrishnan, Srinivasan; Striepen, Boris; Moreno, Silvia N J

2013-01-01

Intracellular pathogens have complex metabolic interactions with their host cells to ensure a steady supply of energy and anabolic building blocks for rapid growth. Here we use the obligate intracellular parasite Toxoplasma gondii to probe this interaction for isoprenoids, abundant lipidic compounds essential to many cellular processes including signaling, trafficking, energy metabolism, and protein translation. Synthesis of precursors for isoprenoids in Apicomplexa occurs in the apicoplast and is essential. To synthesize longer isoprenoids from these precursors, T. gondii expresses a bifunctional farnesyl diphosphate/geranylgeranyl diphosphate synthase (TgFPPS). In this work we construct and characterize T. gondii null mutants for this enzyme. Surprisingly, these mutants have only a mild growth phenotype and an isoprenoid composition similar to wild type parasites. However, when extracellular, the loss of the enzyme becomes phenotypically apparent. This strongly suggests that intracellular parasite salvage FPP and/or geranylgeranyl diphosphate (GGPP) from the host. We test this hypothesis using inhibitors of host cell isoprenoid synthesis. Mammals use the mevalonate pathway, which is susceptible to statins. We document strong synergy between statin treatment and pharmacological or genetic interference with the parasite isoprenoid pathway. Mice can be cured with atorvastatin (Lipitor) from a lethal infection with the TgFPPs mutant. We propose a double-hit strategy combining inhibitors of host and parasite pathways as a novel therapeutic approach against Apicomplexan parasites.
Principal component analysis and the locus of the Fréchet mean in the space of phylogenetic trees.

PubMed

Nye, Tom M W; Tang, Xiaoxian; Weyenberg, Grady; Yoshida, Ruriko

2017-12-01

Evolutionary relationships are represented by phylogenetic trees, and a phylogenetic analysis of gene sequences typically produces a collection of these trees, one for each gene in the analysis. Analysis of samples of trees is difficult due to the multi-dimensionality of the space of possible trees. In Euclidean spaces, principal component analysis is a popular method of reducing high-dimensional data to a low-dimensional representation that preserves much of the sample's structure. However, the space of all phylogenetic trees on a fixed set of species does not form a Euclidean vector space, and methods adapted to tree space are needed. Previous work introduced the notion of a principal geodesic in this space, analogous to the first principal component. Here we propose a geometric object for tree space similar to the [Formula: see text]th principal component in Euclidean space: the locus of the weighted Fréchet mean of [Formula: see text] vertex trees when the weights vary over the [Formula: see text]-simplex. We establish some basic properties of these objects, in particular showing that they have dimension [Formula: see text], and propose algorithms for projection onto these surfaces and for finding the principal locus associated with a sample of trees. Simulation studies demonstrate that these algorithms perform well, and analyses of two datasets, containing Apicomplexa and African coelacanth genomes respectively, reveal important structure from the second principal components.
Haemosporidian infection in captive masked bobwhite quail (Colinus virginianus ridgwayi), an endangered subspecies of the northern bobwhite quail

PubMed Central

Pacheco, M. Andreína; Escalante, Ananias A.; Garner, Michael M.; Bradley, Gregory A.; Aguilar, Roberto F.

2011-01-01

The avian haemosporidian parasites (phylum Apicomplexa) are taxonomically diverse and cosmopolitan in distribution; infecting most bird families. Sources of concern are reports of clinical haemosporidian infections in birds kept as part of zoo and aviary collections. Recently, severe and acute mortality episodes have been reported in masked bobwhite quail (Colinus virginianus ridgwayi), an endangered subspecies from the American Southwest. Two hundred and five eggs of the captive flock held in Arivaca, Arizona, were hatched at a zoo in the American Southwest. Thirty four sub-adult or adult animals had lesions associated with tissue phases of hemoparasites, especially vasculitis, ventricular leiomyositis and ulcerative pododermatitis. Molecular techniques applied to blood collected from the zoo’s last twelve remaining animals resulted in the detection of a Plasmodium juxtanucleare-like and Haemoproteus sp. parasites. A Raven (Corvus corax), in a contiguous exhibit, was positive for the same Plasmodium juxtanucleare-like parasite, but remained asymptomatic for three years following detection. These findings indicate that other birds in the exhibit within the zoo premises could act as reservoirs. We conclude that haemosporidian infections could be a factor in the demise of the captive masked bobwhite quails housed at the zoo. We suggest that active surveillance for haemoporidian parasites should be incorporated as a precaution to ex-situ conservation efforts of susceptible endangered species. PMID:21726940
Theileria parasites secrete a prolyl isomerase to maintain host leukocyte transformation.

PubMed

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

PubMed Central

Marsolier, J.; Perichon, M.; DeBarry, JD.; Villoutreix, BO.; Chluba, J.; Lopez, T.; Garrido, C.; Zhou, XZ.; Lu, KP.; Fritsch, L.; Ait-Si-Ali, S.; Mhadhbi, M; Medjkane, S.; Weitzman, JB.

2014-01-01

Infectious agents develop intricate mechanisms to interact with host cell pathways and hijack the genetic and epigenetic machinery to change phenotypic states. Amongst the Apicomplexa phylum of obligate intracellular parasites which cause veterinary and human diseases, Theileria is the only genus which transforms its mammalian host cells1. Theileria infection of bovine leukocytes induces proliferative and invasive phenotypes associated with activated signalling pathways, notably JNK and AP-12. The transformed phenotypes are reversed by treatment with the theilericidal drug Buparvaquone3. We used comparative genomics to identify a homologue of the Peptidyl Prolyl Isomerase Pin1 (designated TaPin1) in T. annulata which 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 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 isomerisation is thus a conserved mechanism which is important in cancer and is used by Theileria parasites to manipulate host oncogenic signaling. PMID:25624101
First Molecular Characterization of Theileria ornithorhynchi Mackerras, 1959: yet Another Challenge to the Systematics of the Piroplasms.

PubMed

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. Copyright © 2015 Elsevier GmbH. All rights reserved.
The crustacean parasites Ellobiopsis Caullery, 1910 and Thalassomyces Niezabitowski, 1913 form a monophyletic divergent clade within the Alveolata.

PubMed

Gómez, Fernando; López-García, Purificación; Nowaczyk, Antoine; Moreira, David

2009-09-01

The Ellobiopsidae are enigmatic parasites of crustaceans that have been grouped together exclusively on the basis of morphological similarities. Ultrastructural studies have revealed their affiliation within the alveolates, which was confirmed by the phylogenetic analysis of the ribosomal RNA gene (SSU rDNA) sequences of two species of Thalassomyces Niezabitowski, 1913. However, their precise systematic position within this group remains unresolved, since they could not be definitively allied with any particular alveolate group. To better determine the systematic position of ellobiopsids by molecular phylogeny, we sequenced the SSU rDNA from the type-species of the Ellobiopsidae, Ellobiopsis chattoni Caullery, 1910. We found E. chattoni infecting various copepod hosts, Acartia clausi Giesbrecht, Centropages typicus Kröyer and Clausocalanus sp., in the Bay of Marseille, NW Mediterranean Sea, which allowed us to study several stages of the parasite development. A single unicellular multinucleate specimen provided two different sequences of the SSU rDNA gene, indicating the existence of polymorphism at this locus within single individuals. Ellobiopsis Caullery, 1910 and Thalassomyces formed a very divergent and well-supported clade in phylogenetic analyses. This clade appears to be more closely related to the dinoflagellates (including the Syndiniales/Marine Alveolate Group II and the Dinokaryota) and Marine Alveolate Group I than to the other alveolates (Ciliophora, Perkinsozoa and Apicomplexa).
Toxoplasma gondii Antibodies in Bulk Tank Milk Samples of Caprine Dairy Herds.

PubMed

Gazzonis, Alessia Libera; Zanzani, Sergio Aurelio; Stradiotto, Katia; Olivieri, Emanuela; Villa, Luca; Manfredi, Maria Teresa

2018-06-15

A major public health issue, Toxoplasma gondii infection can affect humans mainly via the consumption of animal products from certain species, including small ruminants. Therefore, a regular monitoring of the infection in ovine and caprine populations is advisable for the control of human and animal toxoplasmosis. Antibody detection in individual and bulk tank milk may represent a valid alternative to serological analysis, being its collection easy and not affecting animal welfare. Many serological tools for milk analysis have already been validated for several parasites, including Apicomplexa. Thus, the aim of the present study was to obtain epidemiological data on T. gondii infection through the detection of antibodies in bulk tank milk of dairy goat herds from an important area for caprine dairy production (Northern Italy). The performance of a commercial ELISA was first evaluated for analysis on caprine milk samples, using a panel of serum-milk pairs of goats naturally infected by T. gondii. The analysis on bulk tank milk confirmed the presence of antibodies anti-T. gondii in 59% of the samples. Toxoplasma gondii antibody positivity was more frequently found in farms reared under extensive (64.9%) or semi-intensive systems (68.7%) in comparison to intensive farms (51.1%). Analysis on milk revealed to be a valid alternative to serological tests, being easily applied in large-scale epidemiological surveys and for continuous monitoring of T. gondii infection.
Morphological, morphometric, and molecular characterization of Hepatozoon spp. (Apicomplexa, Hepatozoidae) from naturally infected Caudisona durissa terrifica (Serpentes, Viperidae).

PubMed

Moço, Tatiana Cristina; da Silva, Reinaldo José; Madeira, Newton Goulart; Dos Santos Paduan, Karina; Rubini, Adriano Stefani; Leal, Denise Dutra Menezes; O'Dwyer, Lucia Helena

2012-04-01

Hepatozoon spp. are the most frequent intracellular protozoa in snakes. Considering the variety of parasites infecting specimens of Caudisona durissa terrifica and the divergent data in literature where only two species, Hepatozoon romani and Hepatozoon capsulata, are described, the aim of this study was to morphologically, morphometrically, and molecularly characterize Hepatozoon spp. from some naturally infected specimens of C. durissa terrifica, and observe changes caused by these protozoa in parasitized erythrocytes. Four snakes were examined. Two of them had two morphological distinct gamonts, while the other two had only one type of gamont. The six distinct gamonts were provisionally named gamonts A, B, C, D, E, and F. Statistical analysis, however, confirmed the existence of only four parasite populations, those which were capable of inducing significant alterations in determined red blood cells variables. Attempts to infect Aedes aegypti and Culex quinquefasciatus mosquitoes were done for each snake specimen. Some mosquitoes became infected and oocysts were recovered and measured. The detection of Hepatozoon DNA was obtained with success but the molecular characterization was unable to differentiate species of the samples, with respect to the fragment studied.

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

PubMed

Maia, João P; Crottini, Angelica; Harris, David James

2014-01-01

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. © J.P. Maia et al., published by EDP Sciences, 2014.
Microscopic and molecular characterization of Hepatozoon domerguei (Apicomplexa) and Foleyella furcata (Nematoda) in wild endemic reptiles from Madagascar

PubMed Central

Maia, João P.; Crottini, Angelica; Harris, David James

2014-01-01

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. PMID:25224723
Life cycle of Hepatozoon canis (Apicomplexa: Adeleorina: Hepatozoidae) in the tick Rhipicephalus sanguineus and domestic dog (Canis familiaris).

PubMed

Baneth, Gad; Samish, Michael; Shkap, Varda

2007-04-01

The life cycle of the apicomplexan protozoon Hepatozoon canis in its natural hosts Rhipicephalus sanguineus (tick) and Canis familiaris (domestic dog) was studied in an experimental infection. Tick nymphs were fed on a naturally infected dog, or they were infected by percutaneous injection of blood. Dogs were inoculated by ingestion of adult ticks containing mature oocysts. Gamonts were in syzygy 24 hr after percutaneous injection of ticks. Early oocysts were detected 96 hr after nymph repletion, and mature oocysts in adult ticks were infective to dogs 40 days postmolt. Merogony was detected in dog bone marrow from 13 days postinoculation (PI) and included meronts containing 20-30 micromerozoites, and a second type with 2-4 macromerozoites. Monozoic cysts were observed in the spleen in conjunction with merogony. Gamontogony with infection of leukocytes by micromerozoites occurred from 26 days PI, and gamont parasitemia, which completed the life cycle, was detected 28 days PI. The length of the life cycle from nymphal attachment to parasitemia in dogs was 81 days. Increased body temperatures were evident from 16 to 27 days PI and paralleled the time of intensive bone marrow merogony. Skeletal pain and recumbency were manifested in 2 dogs. This study further elucidates the life cycle of H. canis and provides a sequential morphologic description of H. canis merogony, gamontogony, and sporogony.
Cryptosporidium proliferans n. sp. (Apicomplexa: Cryptosporidiidae): Molecular and Biological Evidence of Cryptic Species within Gastric Cryptosporidium of Mammals

PubMed Central

Kváč, Martin; Havrdová, Nikola; Hlásková, Lenka; Daňková, Tereza; Kanděra, Jiří; Ježková, Jana; Vítovec, Jiří; Sak, Bohumil; Ortega, Ynes; Xiao, Lihua; Modrý, David; Chelladurai, Jeba Rose Jennifer Jesudoss; Prantlová, Veronika; McEvoy, John

2016-01-01

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. PMID:26771460
Comparison of the ITS1 and ITS2 rDNA in Emeria callospermophili (Apicomplexa: Eimeriidae) from Sciurid Rodents

PubMed Central

Motriuk-Smith, Dagmara; Seville, R Scott; Quealy, Leah; Oliver, Clinton E.

2011-01-01

The taxonomy of the coccidia has historically been morphologically based. The purpose of this study was to establish if conspecificity of isolates of Eimeria callospermophili from 4 ground-dwelling squirrel hosts (Rodentia: Sciuridae) is supported by comparison of rDNA sequence data and to examine how this species relates to eimerian species from other sciurid hosts. Eimeria callospermophili was isolated from 4 wild caught hosts, i.e., Urocitellus elegans, Cynomys leucurus, Marmota flaviventris, and Cynomys ludovicianus. The ITS1 and ITS2 genomic rDNA sequences were PCR generated, sequenced, and analyzed. The highest intraspecific pairwise distance values of 6.0% in ITS1 and 7.1% in ITS2 were observed in C. leucurus. Interspecific pairwise distance values greater than 5% do not support E. callospermophili conspecificity. Generated E. callospermophili sequences were compared to Eimeria lancasterensis from Sciuris niger and Sciurus niger cinereus, and Eimeria ontarioensis from S. niger. A single well-supported clade was formed by E. callospermophili amplicons in Neighbor Joining and Maximum Parsimony analyses. However, within the clade there was little evidence of host or geographic structuring of the species. PMID:21506777
Choleoeimeria ghaffari n. sp. (Apicomplexa: Eimeriidae) from the gallbladder of Eryx jayakari Boulenger (Serpentes: Boidae) in Saudi Arabia.

PubMed

Abdel-Baki, Abdel-Azeem S; Al-Quraishy, Saleh; Duszynski, Donald W

2014-02-01

Choleoeimeria ghaffari n. sp. is described from the gallbladder of Eryx jayakari Boulenger in Saudi Arabia. Oöcysts are tetrasporocystic, cylindroidal, 23 × 14 μm, with a smooth bi-layered wall and length/width ratio of 1.5, without micropyle, oöcyst residuum and polar granule. Sporocysts are subspheroidal to ellipsoidal, 8 × 6 μm, with length/width ratio of 1.4, without Stieda, sub-Stieda and para-Stieda bodies but with sporocyst residuum. Sporozoites are banana-shaped measuring 10 × 1.5 μm. The endogenous development was found to occur in the gallbladder epithelium and the extrahepatic bile ducts. Mature meronts are spheroidal, c.10 μm wide, and suspected to produce 12-16 merozoites. Microgamonts are irregular in shape, 13 × 10 μm, whereas macrogamonts are mostly subspheroidal, c.12 μm wide, with a prominent centrally-located nucleus. Based on oöcyst morphology and the site of endogenous development (epithelium of the gallbladder and bile ducts) the new eimeriid coccidian was placed in the genus Choleoeimeria Paperna & Landsberg, 1989.
New species of Eimeria (Apicomplexa: Eimeriidae) from Thrichomys fosteri and Clyomys laticeps (Rodentia: Echimyidae) of the Brazilian Pantanal.

PubMed

Barreto, Wanessa Teixeira Gomes; Viana, Lúcio André; Santos, Filipe Martins; de Oliveira Porfírio, Grasiela Edith; Perdomo, Alessandra Cabral; da Silva, Alanderson Rodrigues; de Sousa, Keyla Carstens Marques; de Oliveira, Michel Angelo Constantino; Herrera, Heitor Miraglia; de Andrade, Gisele Braziliano

2017-11-01

The echimyid rodents Thrichomys fosteri and Clyomys laticeps are among the most commonly recorded small mammals in the Pantanal wetland of Brazil. These species play important ecological roles since they are the basis of the food chain of some predators and are parasitized by some pathogens. Knowledge of the eimerians that parasitize echimyid rodents in Brazil is absent, and only one report is available for South America. We therefore investigated parasitism by coccidians in the echimyids T. fosteri and C. laticeps in the Pantanal. Using morphological and morphometric features and associated statistical analyses, we describe five new eimerian species parasitizing T. fosteri (Eimeria nhecolandensis n. sp., Eimeria jansenae n. sp., and Eimeria fosteri n. sp.) and C. laticeps (E. nhecolandensis n. sp., Eimeria corumbaensis n. sp., and Eimeria laticeps n. sp.) in different types of infection associations. We document the developmental forms in the tissues, and describe lesions in the enteric tract of some infected animals. We also discuss some approaches regarding epidemiological and ecological data. Our results demonstrate that echimyid rodents in the Brazilian Pantanal are important hosts for the maintenance of enteric coccidia. Moreover, in some circumstances, this parasitism may threaten the health of the hosts.
Two new species of Eimeria (Apicomplexa, Eimeriidae) from tree skinks, Prasinohaema spp. (Sauria: Scincidae), from Papua New Guinea

USGS Publications Warehouse

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

USGS Publications Warehouse

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).
Effect of tamoxifen on the sphingolipid biosynthetic pathway in the different intraerythrocytic stages of the apicomplexa Plasmodium falciparum.

PubMed

Piñero, Tamara A; Landoni, Malena; Duschak, Vilma G; Katzin, Alejandro M; Couto, Alicia S

2018-03-18

Parasites of the genus Plasmodium responsible for Malaria are obligate intracellular pathogens residing in mammalian red blood cells, hepatocytes, or mosquito midgut epithelial cells. Regarding that detailed knowledge on the sphingolipid biosynthetic pathway of the apicomplexan protozoan parasites is scarce, different stages of Plasmodium falciparum were treated with tamoxifen in order to evaluate the effects of this drug on the glycosphingolipid biosynthesis. Thin layer chromatography, High performance reverse phase chromatography and UV-MALDI-TOF mass spectrometry were the tools used for the analysis. In the ring forms, the increase of NBD-phosphatidyl inositol biosynthesis was notorious but differences at NBD-GlcCer levels were undetectable. In trophozoite forms, an abrupt decrease of NBD-acylated GlcDHCer and NBD-GlcDHCer in addition to an increase of NBD-PC biosynthesis was observed. On the contrary, in schizonts, tamoxifen seems not to be producing substantial changes in lipid biosynthesis. Our findings indicate that in this parasite, tamoxifen is exerting an inhibitory action on Glucosylceramidesynthase and sphingomyelin synthase levels. Moreover, regarding that Plasmodium does not biosynthesize inositolphosphoceramides, the accumulation of phosphatidylinositol should indicate an inhibitory action on glycosylinositol phospholipid synthesis. Copyright © 2018 Elsevier Inc. All rights reserved.
Endogenous Life Cycle of Eimeria marmosopos (Apicomplexa: Eimeriidae) from the Opossum, Didelphis marsupialis (Didelphimorphia: Didelphidae) in Costa Rica.

PubMed

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.
A NEW SPECIES OF CARYOSPORA (APICOMPLEXA: EIMERIIDAE) FROM THE FLATHEAD SNAKE, TANTILLA GRACILIS (OPHIDIA: COLUBRIDAE), IN SOUTHEASTERN OKLAHOMA

PubMed Central

McAllister, Chris T.; Roehrs, Zachary P.; Seville, R. Scott

2012-01-01

A single flathead snake, Tantilla gracilis, collected in early October 2010 from Choctaw County, Oklahoma, was found to harbor an undescribed species of Caryospora. Oocysts of Caryospora choctawensis n. sp. were spherical to subspherical, 15.8 × 15.0 (14–18 × 14–16) μm with a thick bilayered wall and a shape index (length/width) of 1.1. A micropyle and an oocyst residuum are absent but prominent Stieda and bubble-like sub-Stieda bodies were present as well as a bilobed polar granule near the oocyst wall. Sporocysts were ovoidal, 10.8 × 9.0 (10–12 × 8–9) μm with a shape index of 1.3. The sporocyst residuum was spherical and composed of a cluster of granules often membrane-bound. This is the second time a caryosporan species has been reported from T. gracilis, but the first coccidian ever described from a reptilian host in Oklahoma. Additional T. gracilis from Arkansas (n = 6), Oklahoma (n = 1), and Texas (n = 7) were examined and a single specimen from Newton County, Arkansas, harbored Caryospora gracilis Upton, McAllister, Trauth, and Bibb, 1992, previously reported from T. gracilis collected in Arkansas and Texas. PMID:22191621
Effects of methylglyoxal bis(guanylhydrazone) and two phenylated analogues on S-adenosylmethionine decarboxylase activity from Eimeria stiedai (Apicomplexa).

PubMed

San-Martín Núñez, B; Alunda, J M; Balaña-Fouce, R; Ordóñez Escudero, D

1987-01-01

1. Activity of S-adenosylmethionine decarboxylase, one of the rate-limiting enzymes of polyamine biosynthesis, was determined in oocysts of Eimeria stiedai, a coccidian parasite of the rabbit. 2. Several properties of the enzyme were compared to the mammalian enzyme. It showed considerably less substrate affinity than the analog enzyme from the rabbit. 3. The E. stiedai enzyme showed a low sensitivity to methylglyoxal bis(guanylhydrazone), a frequently used inhibitor of the enzyme in mammals, and two phenylated derivatives. 4. Results with the inhibitors are discussed in view of their potential use in chemotherapy.
Identification of a Divergent Environmental DNA Sequence Clade Using the Phylogeny of Gregarine Parasites (Apicomplexa) from Crustacean Hosts

PubMed Central

Rueckert, Sonja; Simdyanov, Timur G.; Aleoshin, Vladimir V.; Leander, Brian S.

2011-01-01

Background Environmental SSU rDNA surveys have significantly improved our understanding of microeukaryotic diversity. Many of the sequences acquired using this approach are closely related to lineages previously characterized at both morphological and molecular levels, making interpretation of these data relatively straightforward. Some sequences, by contrast, appear to be phylogenetic orphans and are sometimes inferred to represent “novel lineages” of unknown cellular identity. Consequently, interpretation of environmental DNA surveys of cellular diversity rely on an adequately comprehensive database of DNA sequences derived from identified species. Several major taxa of microeukaryotes, however, are still very poorly represented in these databases, and this is especially true for diverse groups of single-celled parasites, such as gregarine apicomplexans. Methodology/Principal Findings This study attempts to address this paucity of DNA sequence data by characterizing four different gregarine species, isolated from the intestines of crustaceans, at both morphological and molecular levels: Thiriotia pugettiae sp. n. from the graceful kelp crab (Pugettia gracilis), Cephaloidophora cf. communis from two different species of barnacles (Balanus glandula and B. balanus), Heliospora cf. longissima from two different species of freshwater amphipods (Eulimnogammarus verrucosus and E. vittatus), and Heliospora caprellae comb. n. from a skeleton shrimp (Caprella alaskana). SSU rDNA sequences were acquired from isolates of these gregarine species and added to a global apicomplexan alignment containing all major groups of gregarines characterized so far. Molecular phylogenetic analyses of these data demonstrated that all of the gregarines collected from crustacean hosts formed a very strongly supported clade with 48 previously unidentified environmental DNA sequences. Conclusions/Significance This expanded molecular phylogenetic context enabled us to establish a major clade of intestinal gregarine parasites and infer the cellular identities of several previously unidentified environmental SSU rDNA sequences, including several sequences that have formerly been discussed broadly in the literature as a suspected “novel” lineage of eukaryotes. PMID:21483868
First case of a naturally acquired human infection with Plasmodium cynomolgi

PubMed Central

2014-01-01

Since 1960, a total of seven species of monkey malaria have been reported as transmissible to man by mosquito bite: Plasmodium cynomolgi, Plasmodium brasilianum, Plasmodium eylesi, Plasmodium knowlesi, Plasmodium inui, Plasmodium schwetzi and Plasmodium simium. With the exception of P. knowlesi, none of the other species has been found to infect humans in nature. In this report, it is described the first known case of a naturally acquired P. cynomolgi malaria in humans. The patient was a 39-year-old woman from a malaria-free area with no previous history of malaria or travel to endemic areas. Initially, malaria was diagnosed and identified as Plasmodium malariae/P. knowlesi by microscopy in the Terengganu State Health Department. Thick and thin blood films stained with 10% Giemsa were performed for microscopy examination. Molecular species identification was performed at the Institute for Medical Research (IMR, Malaysia) and in the Malaria & Emerging Parasitic Diseases Laboratory (MAPELAB, Spain) using different nested PCR methods. Microscopic re-examination in the IMR showed characteristics of Plasmodium vivax and was confirmed by a nested PCR assay developed by Snounou et al. Instead, a different PCR assay plus sequencing performed at the MAPELAB confirmed that the patient was infected with P. cynomolgi and not with P. vivax. This is the first report of human P. cynomolgi infection acquired in a natural way, but there might be more undiagnosed or misdiagnosed cases, since P. cynomolgi is morphologically indistinguishable from P. vivax, and one of the most used PCR methods for malaria infection detection may identify a P. cynomolgi infection as P. vivax. Simian Plasmodium species may routinely infect humans in Southeast Asia. New diagnostic methods are necessary to distinguish between the human and monkey malaria species. Further epidemiological studies, incriminating also the mosquito vector(s), must be performed to know the relevance of cynomolgi malaria and its
First case of a naturally acquired human infection with Plasmodium cynomolgi.

PubMed

Ta, Thuy H; Hisam, Shamilah; Lanza, Marta; Jiram, Adela I; Ismail, NorParina; Rubio, José M

2014-02-24

Since 1960, a total of seven species of monkey malaria have been reported as transmissible to man by mosquito bite: Plasmodium cynomolgi, Plasmodium brasilianum, Plasmodium eylesi, Plasmodium knowlesi, Plasmodium inui, Plasmodium schwetzi and Plasmodium simium. With the exception of P. knowlesi, none of the other species has been found to infect humans in nature. In this report, it is described the first known case of a naturally acquired P. cynomolgi malaria in humans.The patient was a 39-year-old woman from a malaria-free area with no previous history of malaria or travel to endemic areas. Initially, malaria was diagnosed and identified as Plasmodium malariae/P. knowlesi by microscopy in the Terengganu State Health Department. Thick and thin blood films stained with 10% Giemsa were performed for microscopy examination. Molecular species identification was performed at the Institute for Medical Research (IMR, Malaysia) and in the Malaria & Emerging Parasitic Diseases Laboratory (MAPELAB, Spain) using different nested PCR methods.Microscopic re-examination in the IMR showed characteristics of Plasmodium vivax and was confirmed by a nested PCR assay developed by Snounou et al. Instead, a different PCR assay plus sequencing performed at the MAPELAB confirmed that the patient was infected with P. cynomolgi and not with P. vivax.This is the first report of human P. cynomolgi infection acquired in a natural way, but there might be more undiagnosed or misdiagnosed cases, since P. cynomolgi is morphologically indistinguishable from P. vivax, and one of the most used PCR methods for malaria infection detection may identify a P. cynomolgi infection as P. vivax.Simian Plasmodium species may routinely infect humans in Southeast Asia. New diagnostic methods are necessary to distinguish between the human and monkey malaria species. Further epidemiological studies, incriminating also the mosquito vector(s), must be performed to know the relevance of cynomolgi malaria and its
Microscopic and molecular studies of the diversity of free-living protozoa in meat-cutting plants.

PubMed

Vaerewijck, Mario J M; Sabbe, Koen; Baré, Julie; Houf, Kurt

2008-09-01

The diversity of free-living protozoa in five meat-cutting plants was determined. Light microscopy after enrichment culturing was combined with sequencing of PCR-amplified, denaturing gradient gel electrophoresis (DGGE)-separated 18S rRNA gene fragments, which was used as a fast screening method. The general results of the survey showed that a protozoan community of amoebae, ciliates, and flagellates was present in all of the plants. Protozoa were detected mainly in floor drains, in standing water on the floor, on soiled bars of cutting tables, on plastic pallets, and in out-of-use hot water knife sanitizers, but they were also detected on surfaces which come into direct contact with meat, such as conveyer belts, working surfaces of cutting tables, and needles of a meat tenderizer. After 7 days of incubation at refrigerator temperature, protozoa were detected in about one-half of the enrichment cultures. Based on microscopic observations, 61 morphospecies were found, and Bodo saltans, Bodo spp., Epistylis spp., Glaucoma scintillans, Petalomonas spp., Prodiscophrya collini, and Vannella sp. were the most frequently encountered identified organisms. Sequencing of DGGE bands resulted in identification of a total of 49 phylotypes, including representatives of the Amoebozoa, Chromalveolata, Excavata, Opisthokonta, and Rhizaria. Sequences of small heterotrophic flagellates were affiliated mainly with the Alveolata (Apicomplexa), Stramenopiles (Chrysophyceae), and Rhizaria (Cercozoa). This survey showed that there is high protozoan species richness in meat-cutting plants and that the species included species related to known hosts of food-borne pathogens.
Multiple Metabolic Roles for the Nonphotosynthetic Plastid of the Green Alga Prototheca wickerhamii†

PubMed Central

Borza, Tudor; Popescu, Cristina E.; Lee, Robert W.

2005-01-01

The presence of plastids in diverse eukaryotic lineages that have lost the capacity for photosynthesis is well documented. The metabolic functions of such organelles, however, are poorly understood except in the case of the apicoplast in the Apicomplexa, a group of intracellular parasites including Plasmodium falciparum, and the plastid of the green alga Helicosporidium sp., a parasite for which the only host-free stage identified in nature so far is represented by cysts. As a first step in the reconstruction of plastid functions in a nonphotosynthetic, predominantly free-living organism, we searched for expressed sequence tags (ESTs) that correspond to nucleus-encoded plastid-targeted polypeptides in the green alga Prototheca wickerhamii. From 3,856 ESTs, we found that 71 unique sequences (235 ESTs) correspond to different nucleus-encoded putatively plastid-targeted polypeptides. The identified proteins predict that carbohydrate, amino acid, lipid, tetrapyrrole, and isoprenoid metabolism as well as de novo purine biosynthesis and oxidoreductive processes take place in the plastid of P. wickerhamii. Mg-protoporphyrin accumulation and, therefore, plastid-to-nucleus signaling might also occur in this nonphotosynthetic organism, as we identified a transcript which encodes subunit I of Mg-chelatase, the enzyme which catalyzes the first committed step in chlorophyll synthesis. Our data indicate a far more complex metabolism in P. wickerhamii's plastid compared with the metabolic pathways predicted to be located in the apicoplast of P. falciparum and the plastid of Helicosporidium sp. PMID:15701787
The genome of Eimeria falciformis--reduction and specialization in a single host apicomplexan parasite.

PubMed

Heitlinger, Emanuel; Spork, Simone; Lucius, Richard; Dieterich, Christoph

2014-08-20

The phylum Apicomplexa comprises important unicellular human parasites such as Toxoplasma and Plasmodium. Eimeria is the largest and most diverse genus of apicomplexan parasites and some species of the genus are the causative agent of coccidiosis, a disease economically devastating in poultry. We report a complete genome sequence of the mouse parasite Eimeria falciformis. We assembled and annotated the genome sequence to study host-parasite interactions in this understudied genus in a model organism host. The genome of E. falciformis is 44 Mb in size and contains 5,879 predicted protein coding genes. Comparative analysis of E. falciformis with Toxoplasma gondii shows an emergence and diversification of gene families associated with motility and invasion mainly at the level of the Coccidia. Many rhoptry kinases, among them important virulence factors in T. gondii, are absent from the E. falciformis genome. Surface antigens are divergent between Eimeria species. Comparisons with T. gondii showed differences between genes involved in metabolism, N-glycan and GPI-anchor synthesis. E. falciformis possesses a reduced set of transmembrane transporters and we suggest an altered mode of iron uptake in the genus Eimeria. Reduced diversity of genes required for host-parasite interaction and transmembrane transport allow hypotheses on host adaptation and specialization of a single host parasite. The E. falciformis genome sequence sheds light on the evolution of the Coccidia and helps to identify determinants of host-parasite interaction critical for drug and vaccine development.
Population, genetic, and antigenic diversity of the apicomplexan Eimeria tenella and their relevance to vaccine development

PubMed Central

Blake, Damer P.; Clark, Emily L.; Macdonald, Sarah E.; Thenmozhi, Venkatachalam; Kundu, Krishnendu; Garg, Rajat; Jatau, Isa D.; Ayoade, Simeon; Kawahara, Fumiya; Moftah, Abdalgader; Reid, Adam James; Adebambo, Ayotunde O.; Álvarez Zapata, Ramón; Srinivasa Rao, Arni S. R.; Thangaraj, Kumarasamy; Banerjee, Partha S.; Dhinakar-Raj, G.; Raman, M.; Tomley, Fiona M.

2015-01-01

The phylum Apicomplexa includes serious pathogens of humans and animals. Understanding the distribution and population structure of these protozoan parasites is of fundamental importance to explain disease epidemiology and develop sustainable controls. Predicting the likely efficacy and longevity of subunit vaccines in field populations relies on knowledge of relevant preexisting antigenic diversity, population structure, the likelihood of coinfection by genetically distinct strains, and the efficiency of cross-fertilization. All four of these factors have been investigated for Plasmodium species parasites, revealing both clonal and panmictic population structures with exceptional polymorphism associated with immunoprotective antigens such as apical membrane antigen 1 (AMA1). For the coccidian Toxoplasma gondii only genomic diversity and population structure have been defined in depth so far; for the closely related Eimeria species, all four variables are currently unknown. Using Eimeria tenella, a major cause of the enteric disease coccidiosis, which exerts a profound effect on chicken productivity and welfare, we determined population structure, genotype distribution, and likelihood of cross-fertilization during coinfection and also investigated the extent of naturally occurring antigenic diversity for the E. tenella AMA1 homolog. Using genome-wide Sequenom SNP-based haplotyping, targeted sequencing, and single-cell genotyping, we show that in this coccidian the functionality of EtAMA1 appears to outweigh immune evasion. This result is in direct contrast to the situation in Plasmodium and most likely is underpinned by the biology of the direct and acute coccidian life cycle in the definitive host. PMID:26354122

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

PubMed

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.
Putative Monofunctional Type I Polyketide Synthase Units: A Dinoflagellate-Specific Feature?

PubMed Central

Eichholz, Karsten; Beszteri, Bánk; John, Uwe

2012-01-01

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. PMID:23139807
First report of Hepatozoon (Apicomplexa: Adeleorina) from king ratsnakes (Elaphe carinata) in Shanghai, with description of a new species.

PubMed

Han, Hongyu; Wu, Youling; Dong, Hui; Zhu, Shunhai; Li, Liujia; Zhao, Qiping; Wu, Di; Pei, Enle; Wang, Yange; Huang, Bing

2015-06-01

Hepatozoon species are the most common hemoparasites of snakes. In this study, Hepatozoon parasites were examined for the first time in king rat snakes (Elaphe carinata) from Shanghai, China. All 10 snakes were found to be infected with Hepatozoon gamonts. The gamonts were folded back in a hook-wise fashion for about 3 μm at one end. Parasitemia levels ranged from 4-43 infected erythrocytes per 1,000 examined. The gamonts changed the morphology of the parasitized erythrocytes. Although the gamonts showed some distinct variations in both the parasite and its nucleus, phylogenetic analysis indicated that all the E. carinata in this study formed a monophyletic group, and were distinct from all other published Hepatozoon species. A new species, Hepatozoon chinensis, was proposed based on the molecular and morphologic evidence.
Redescription of Hepatozoon felis (Apicomplexa: Hepatozoidae) based on phylogenetic analysis, tissue and blood form morphology, and possible transplacental transmission

PubMed Central

2013-01-01

Background A Hepatozoon parasite was initially reported from a cat in India in 1908 and named Leucocytozoon felis domestici. Although domestic feline hepatozoonosis has since been recorded from Europe, Africa, Asia and America, its description, classification and pathogenesis have remained vague and the distinction between different species of Hepatozoon infecting domestic and wild carnivores has been unclear. The aim of this study was to carry out a survey on domestic feline hepatozoonosis and characterize it morphologically and genetically. Methods Hepatozoon sp. DNA was amplified by PCR from the blood of 55 of 152 (36%) surveyed cats in Israel and from all blood samples of an additional 19 cats detected as parasitemic by microscopy during routine hematologic examinations. Hepatozoon sp. forms were also characterized from tissues of naturally infected cats. Results DNA sequencing determined that all cats were infected with Hepatozoon felis except for two infected by Hepatozoon canis. A significant association (p = 0.00001) was found between outdoor access and H. felis infection. H. felis meronts containing merozoites were characterized morphologically from skeletal muscles, myocardium and lungs of H. felis PCR-positive cat tissues and development from early to mature meront was described. Distinctly-shaped gamonts were observed and measured from the blood of these H. felis infected cats. Two fetuses from H. felis PCR-positive queens were positive by PCR from fetal tissue including the lung and amniotic fluid, suggesting possible transplacental transmission. Genetic analysis indicated that H. felis DNA sequences from Israeli cats clustered together with the H. felis Spain 1 and Spain 2 sequences. These cat H. felis sequences clustered separately from the feline H. canis sequences, which grouped with Israeli and foreign dog H. canis sequences. H. felis clustered distinctly from Hepatozoon spp. of other mammals. Feline hepatozoonosis caused by H. felis is mostly sub-clinical as a high proportion of the population is infected with no apparent overt clinical manifestations. Conclusions This study aimed to integrate new histopathologic, hematologic, clinical, epidemiological and genetic findings on feline hepatozoonosis and promote the understanding of this infection. The results indicate that feline infection is primarily caused by a morphologically and genetically distinct species, H. felis, which has predilection to infecting muscular tissues, and is highly prevalent in the cat population studied. The lack of previous comprehensively integrated data merits the redescription of this parasite elucidating its parasitological characteristics. PMID:23587213
Redescription of Hepatozoon felis (Apicomplexa: Hepatozoidae) based on phylogenetic analysis, tissue and blood form morphology, and possible transplacental transmission.

PubMed

Baneth, Gad; Sheiner, Alina; Eyal, Osnat; Hahn, Shelley; Beaufils, Jean-Pierre; Anug, Yigal; Talmi-Frank, Dalit

2013-04-15

A Hepatozoon parasite was initially reported from a cat in India in 1908 and named Leucocytozoon felis domestici. Although domestic feline hepatozoonosis has since been recorded from Europe, Africa, Asia and America, its description, classification and pathogenesis have remained vague and the distinction between different species of Hepatozoon infecting domestic and wild carnivores has been unclear. The aim of this study was to carry out a survey on domestic feline hepatozoonosis and characterize it morphologically and genetically. Hepatozoon sp. DNA was amplified by PCR from the blood of 55 of 152 (36%) surveyed cats in Israel and from all blood samples of an additional 19 cats detected as parasitemic by microscopy during routine hematologic examinations. Hepatozoon sp. forms were also characterized from tissues of naturally infected cats. DNA sequencing determined that all cats were infected with Hepatozoon felis except for two infected by Hepatozoon canis. A significant association (p = 0.00001) was found between outdoor access and H. felis infection. H. felis meronts containing merozoites were characterized morphologically from skeletal muscles, myocardium and lungs of H. felis PCR-positive cat tissues and development from early to mature meront was described. Distinctly-shaped gamonts were observed and measured from the blood of these H. felis infected cats. Two fetuses from H. felis PCR-positive queens were positive by PCR from fetal tissue including the lung and amniotic fluid, suggesting possible transplacental transmission. Genetic analysis indicated that H. felis DNA sequences from Israeli cats clustered together with the H. felis Spain 1 and Spain 2 sequences. These cat H. felis sequences clustered separately from the feline H. canis sequences, which grouped with Israeli and foreign dog H. canis sequences. H. felis clustered distinctly from Hepatozoon spp. of other mammals. Feline hepatozoonosis caused by H. felis is mostly sub-clinical as a high proportion of the population is infected with no apparent overt clinical manifestations. This study aimed to integrate new histopathologic, hematologic, clinical, epidemiological and genetic findings on feline hepatozoonosis and promote the understanding of this infection. The results indicate that feline infection is primarily caused by a morphologically and genetically distinct species, H. felis, which has predilection to infecting muscular tissues, and is highly prevalent in the cat population studied. The lack of previous comprehensively integrated data merits the redescription of this parasite elucidating its parasitological characteristics.
Molecular and parasitological survey of Hepatozoon canis (Apicomplexa: Hepatozoidae) in dogs from rural area of Sao Paulo state, Brazil.

PubMed

Rubini, Adriano Stefani; dos Santos Paduan, Karina; Von Ah Lopes, Viviane; O'Dwyer, Lucia Helena

2008-04-01

Hepatozoon canis is a protozoan that infects dogs and is transmitted by the ingestion of the brown dog tick, Rhipicephalus sanguineus. Two distinct species of Hepatozoon genus can infect dogs, H. canis and H. americanum. Routine tests to detect the disease are based on direct examination of gametocytes on Giemsa-stained blood smears. The objectives of this study were the investigation of infection prevalence in rural area dogs, the comparison of diagnostics by blood smear examination and polymerase chain reaction (PCR), and the association of infection with tick infestation. Blood smears, collected by puncture of the cephalic vein and ear margin capillary bed from 150 dogs, were examined. This technique detected 17 positive animals (11.3%), with 14 (9.3%) in peripheral blood and seven (4.7%) in cephalic vein blood. PCR tests detected 80 (53.3%) positive animals. R. sanguineus and Amblyomma spp. were found in 36 of the dogs (24%), in equal proportions. The identified species for Amblyomma genus were A. cajennense and A. ovale. Data analysis showed that PCR was much more sensitive when compared to blood smear examination. Hepatozoon species was previously identified as closely related to H. canis.
Two new species of Isospora (Apicomplexa: Eimeriidae) from skinks Emoia spp. (Sauria: Scincidae), from Fiji and Papua New Guinea

USGS Publications Warehouse

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

PubMed

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

2013-08-01

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.
A new eimerian species (Apicomplexa: Eimeriidae) from the blue-fronted Amazon parrot Amazona aestiva L. (Aves: Psittacidae) in Brazil.

PubMed

Hofstatter, P G; Guaraldo, A M A

2011-12-01

The Neotropical psittacine species Amazona aestiva, commonly known as the blue-fronted Amazon, is one of the most common and best-known psittacine birds kept as a pet worldwide. However, very little is known about the diseases or parasites of these birds. In this study, we describe a new species, Eimeria aestivae, associated with these parrots. The new species is characterized by: ovoid smooth oocysts (n = 60), 36.8 (33.2-41.5) × 23.7 (21.7-25.7) µm, length/width ratio = 1.55; polar granule present; ellipsoidal sporocysts (n = 25), 19.8 (17.5-21.6) × 9.3 (8.3-9.9) µm; Stieda, sub-Stieda body, and sporocyst residuum present. Sporozoites (n = 20), 2 per sporocyst, elongate and curved, 17.6 (15.8-19.2) × 3.8 (3.2-4.8) µm; each with 2 refractile bodies. The oocysts of the other 2 eimerian species described for Amazona are larger than those of the presented species, but they all seem to be closely related because of some similarities among them.
A new species of Cystoisospora Frenkel, 1977 (Apicomplexa: Sarcocystidae) from Oecomys mamorae Thomas (Rodentia: Cricetidae) in the Brazilian Pantanal.

PubMed

Barreto, Wanessa Teixeira Gomes; de Andrade, Gisele Braziliano; Viana, Lúcio André; de Oliveira Porfírio, Grasiela Edith; Santos, Filipe Martins; Perdomo, Alessandra Cabral; do Carmo, Jéssica Soares; da Silva, Alanderson Rodrigues; Maltezo, Taynara Rocha; Herrera, Heitor Miraglia

2018-05-01

Despite the great diversity of coccidians, to our knowledge, no coccidian infections have been described in Oecomys spp. In this context, we examined Oecomys mamorae Thomas (Rodentia: Cricetidae) from the Brazilian Pantanal for infections with enteric coccidia. Nine individuals were sampled, and one was found to be infected. The oöcysts were recovered through centrifugal flotation in sugar solution. Using morphological and morphometric features, we described a new species of Cystoisospora Frenkel, 1977. Sporulated oöcysts were ovoidal 20.0-29.1 × 16.4-23.2 (26.7 × 21.2) µm and contained two sporocysts, 12.9-19.1 × 9.4-13.9 (16.4 × 12.4) µm, each with four banana-shaped sporozoites. Polar granule and oöcyst residuum were both absent. We documented the developmental forms in the small intestine and described the histopathological lesions in the enteric tract. Our results indicate that the prevalence of Cystoisospora mamorae n. sp. in O. mamorae is low, and tissue damage in the enteric tract is mild, even in the presence of coccidian developmental stages.
Four new species of coccidia (Apicomplexa: Eimeriidae) from Owen Stanley Skinks, Papuascincus stanleyanus (Sauria: Scincidae), from Papua New Guinea

USGS Publications Warehouse

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.
The Evolutionary History of Sarco(endo)plasmic Calcium ATPase (SERCA)

PubMed Central

Altshuler, Ianina; Vaillant, James J.; Xu, Sen; Cristescu, Melania E.

2012-01-01

Investigating the phylogenetic relationships within physiologically essential gene families across a broad range of taxa can reveal the key gene duplication events underlying their family expansion and is thus important to functional genomics studies. P-Type II ATPases represent a large family of ATP powered transporters that move ions across cellular membranes and includes Na+/K+ transporters, H+/K+ transporters, and plasma membrane Ca2+ pumps. Here, we examine the evolutionary history of one such transporter, the Sarco(endo)plasmic reticulum calcium ATPase (SERCA), which maintains calcium homeostasis in the cell by actively pumping Ca2+ into the sarco(endo)plasmic reticulum. Our protein-based phylogenetic analyses across Eukaryotes revealed two monophyletic clades of SERCA proteins, one containing animals, fungi, and plants, and the other consisting of plants and protists. Our analyses suggest that the three known SERCA proteins in vertebrates arose through two major gene duplication events after the divergence from tunicates, but before the separation of fishes and tetrapods. In plants, we recovered two SERCA clades, one being the sister group to Metazoa and the other to Apicomplexa clade, suggesting an ancient duplication in an early eukaryotic ancestor, followed by subsequent loss of one copy in Opisthokonta, the other in protists, and retention of both in plants. We also report relatively recent and independent gene duplication events within invertebrate taxa including tunicates and the leech Helobdella robusta. Thus, it appears that both ancient and recent gene duplication events have played an important role in the evolution of this ubiquitous gene family across the eukaryotic domain. PMID:23285113
The evolutionary history of sarco(endo)plasmic calcium ATPase (SERCA).

PubMed

Altshuler, Ianina; Vaillant, James J; Xu, Sen; Cristescu, Melania E

2012-01-01

Investigating the phylogenetic relationships within physiologically essential gene families across a broad range of taxa can reveal the key gene duplication events underlying their family expansion and is thus important to functional genomics studies. P-Type II ATPases represent a large family of ATP powered transporters that move ions across cellular membranes and includes Na(+)/K(+) transporters, H(+)/K(+) transporters, and plasma membrane Ca(2+) pumps. Here, we examine the evolutionary history of one such transporter, the Sarco(endo)plasmic reticulum calcium ATPase (SERCA), which maintains calcium homeostasis in the cell by actively pumping Ca(2+) into the sarco(endo)plasmic reticulum. Our protein-based phylogenetic analyses across Eukaryotes revealed two monophyletic clades of SERCA proteins, one containing animals, fungi, and plants, and the other consisting of plants and protists. Our analyses suggest that the three known SERCA proteins in vertebrates arose through two major gene duplication events after the divergence from tunicates, but before the separation of fishes and tetrapods. In plants, we recovered two SERCA clades, one being the sister group to Metazoa and the other to Apicomplexa clade, suggesting an ancient duplication in an early eukaryotic ancestor, followed by subsequent loss of one copy in Opisthokonta, the other in protists, and retention of both in plants. We also report relatively recent and independent gene duplication events within invertebrate taxa including tunicates and the leech Helobdella robusta. Thus, it appears that both ancient and recent gene duplication events have played an important role in the evolution of this ubiquitous gene family across the eukaryotic domain.
Comparative genome analysis reveals a conserved family of actin-like proteins in apicomplexan parasites

PubMed Central

Gordon, Jennifer L; Sibley, L David

2005-01-01

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. PMID:16343347
Gene gain and loss during evolution of obligate parasitism in the white rust pathogen of Arabidopsis thaliana.

PubMed

Kemen, Eric; Gardiner, Anastasia; Schultz-Larsen, Torsten; Kemen, Ariane C; Balmuth, Alexi L; Robert-Seilaniantz, Alexandre; Bailey, Kate; Holub, Eric; Studholme, David J; Maclean, Dan; Jones, Jonathan D G

2011-07-01

Biotrophic eukaryotic plant pathogens require a living host for their growth and form an intimate haustorial interface with parasitized cells. Evolution to biotrophy occurred independently in fungal rusts and powdery mildews, and in oomycete white rusts and downy mildews. Biotroph evolution and molecular mechanisms of biotrophy are poorly understood. It has been proposed, but not shown, that obligate biotrophy results from (i) reduced selection for maintenance of biosynthetic pathways and (ii) gain of mechanisms to evade host recognition or suppress host defence. Here we use Illumina sequencing to define the genome, transcriptome, and gene models for the obligate biotroph oomycete and Arabidopsis parasite, Albugo laibachii. A. laibachii is a member of the Chromalveolata, which incorporates Heterokonts (containing the oomycetes), Apicomplexa (which includes human parasites like Plasmodium falciparum and Toxoplasma gondii), and four other taxa. From comparisons with other oomycete plant pathogens and other chromalveolates, we reveal independent loss of molybdenum-cofactor-requiring enzymes in downy mildews, white rusts, and the malaria parasite P. falciparum. Biotrophy also requires "effectors" to suppress host defence; we reveal RXLR and Crinkler effectors shared with other oomycetes, and also discover and verify a novel class of effectors, the "CHXCs", by showing effector delivery and effector functionality. Our findings suggest that evolution to progressively more intimate association between host and parasite results in reduced selection for retention of certain biosynthetic pathways, and particularly reduced selection for retention of molybdopterin-requiring biosynthetic pathways. These mechanisms are not only relevant to plant pathogenic oomycetes but also to human pathogens within the Chromalveolata.
Gene Gain and Loss during Evolution of Obligate Parasitism in the White Rust Pathogen of Arabidopsis thaliana

PubMed Central

Kemen, Eric; Gardiner, Anastasia; Schultz-Larsen, Torsten; Kemen, Ariane C.; Balmuth, Alexi L.; Robert-Seilaniantz, Alexandre; Bailey, Kate; Holub, Eric; Studholme, David J.; MacLean, Dan; Jones, Jonathan D. G.

2011-01-01

Biotrophic eukaryotic plant pathogens require a living host for their growth and form an intimate haustorial interface with parasitized cells. Evolution to biotrophy occurred independently in fungal rusts and powdery mildews, and in oomycete white rusts and downy mildews. Biotroph evolution and molecular mechanisms of biotrophy are poorly understood. It has been proposed, but not shown, that obligate biotrophy results from (i) reduced selection for maintenance of biosynthetic pathways and (ii) gain of mechanisms to evade host recognition or suppress host defence. Here we use Illumina sequencing to define the genome, transcriptome, and gene models for the obligate biotroph oomycete and Arabidopsis parasite, Albugo laibachii. A. laibachii is a member of the Chromalveolata, which incorporates Heterokonts (containing the oomycetes), Apicomplexa (which includes human parasites like Plasmodium falciparum and Toxoplasma gondii), and four other taxa. From comparisons with other oomycete plant pathogens and other chromalveolates, we reveal independent loss of molybdenum-cofactor-requiring enzymes in downy mildews, white rusts, and the malaria parasite P. falciparum. Biotrophy also requires “effectors” to suppress host defence; we reveal RXLR and Crinkler effectors shared with other oomycetes, and also discover and verify a novel class of effectors, the “CHXCs”, by showing effector delivery and effector functionality. Our findings suggest that evolution to progressively more intimate association between host and parasite results in reduced selection for retention of certain biosynthetic pathways, and particularly reduced selection for retention of molybdopterin-requiring biosynthetic pathways. These mechanisms are not only relevant to plant pathogenic oomycetes but also to human pathogens within the Chromalveolata. PMID:21750662
Wet-surface–enhanced ellipsometric contrast microscopy identifies slime as a major adhesion factor during bacterial surface motility

PubMed Central

Ducret, Adrien; Valignat, Marie-Pierre; Mouhamar, Fabrice; Mignot, Tâm; Theodoly, Olivier

2012-01-01

In biology, the extracellular matrix (ECM) promotes both cell adhesion and specific recognition, which is essential for central developmental processes in both eukaryotes and prokaryotes. However, live studies of the dynamic interactions between cells and the ECM, for example during motility, have been greatly impaired by imaging limitations: mostly the ability to observe the ECM at high resolution in absence of specific staining by live microscopy. To solve this problem, we developed a unique technique, wet-surface enhanced ellipsometry contrast (Wet-SEEC), which magnifies the contrast of transparent organic materials deposited on a substrate (called Wet-surf) with exquisite sensitivity. We show that Wet-SEEC allows both the observation of unprocessed nanofilms as low as 0.2 nm thick and their accurate 3D topographic reconstructions, directly by standard light microscopy. We next used Wet-SEEC to image slime secretion, a poorly defined property of many prokaryotic and eukaryotic organisms that move across solid surfaces in absence of obvious extracellular appendages (gliding). Using combined Wet-SEEC and fluorescent-staining experiments, we observed slime deposition by gliding Myxococcus xanthus cells at unprecedented resolution. Altogether, the results revealed that in this bacterium, slime associates preferentially with the outermost components of the motility machinery and promotes its adhesion to the substrate on the ventral side of the cell. Strikingly, analogous roles have been proposed for the extracellular proteoglycans of gliding diatoms and apicomplexa, suggesting that slime deposition is a general means for gliding organisms to adhere and move over surfaces. PMID:22665761
[Rat cardiomyocyte remodeling after neonatal cryptosporidiosis. II. Elongation, excessive polyploidization and HIF-1alpha overexpression].

PubMed

Anatskaia, O V; Sidorenko, N V; Matveev, I V; Kropotov, A V; Vinogradov, A E

2012-01-01

Retrospective epidemyological studies evidence that infant diseases leave survivors with an increased susceptibility to cardiovascular diseases in later life. At the same time, the mechanisms of this link remain poorly understood. Based on medical statistics reporting that infectious gastroenteritis is the most common cause of maladies in babies, infants and children, we analysed the effects of moderate cryptosporidial gastroenteritis on the heart and ventricular cardiomyocyte remodelling in rats of the first month of life. The disease was challenged by a worldwide human protozoic pathogen Cryptosporidium parvum (Apicomplexa, Sporozoa). The main symptoms manifested in the growth retardation moderate diarrhea. Using real-time PCR, cytophotometry, confocal microscopy and image analysis, we indicated that cryptosporidiosis was associated, with the atrophy heart and the elongation, narrowing, protein content decrease and hyperpolyploidization of cardiomyocytes and the moderate overexpression of hypoxia inducible factor 1alpha (HIF-1alpha) mRNA. Cardiomyocyte shape remodeling and heart atrophy presented in all age groups. The severity of these changes, hovewer, declined gradually from younger to older groups. In contrast, hyperpolyploidization and HIF-1alpha mRNA overexpression were registered mainly among animals aged between 6 and 13 days, and were barely detected and non-significant in older age groups. In the rat the time period covering 6-13 days after birth is known to coincide with the intensive cardiomyocyte polyploidization and the switch from proliferation to hypertrophy. Thus, our data indicate that neonatal cryptosporidiosis may be potential cardiovascular diseases risk factor and that one of the critical time windows for the growing heart covers the time period when cardiomyocyte undergo polyploidization.
A robust mass spectrometry method for rapid profiling of erythrocyte ghost membrane proteomes.

PubMed

Fye, Haddy K S; Mrosso, Paul; Bruce, Lesley; Thézénas, Marie-Laëtitia; Davis, Simon; Fischer, Roman; Rwegasira, Gration L; Makani, Julie; Kessler, Benedikt M

2018-01-01

Red blood cell (RBC) physiology is directly linked to many human disorders associated with low tissue oxygen levels or anemia including chronic obstructive pulmonary disease, congenital heart disease, sleep apnea and sickle cell anemia. Parasites such as Plasmodium spp. and phylum Apicomplexa directly target RBCs, and surface molecules within the RBC membrane are critical for pathogen interactions. Proteomics of RBC membrane 'ghost' fractions has therefore been of considerable interest, but protocols described to date are either suboptimal or too extensive to be applicable to a larger set of clinical cohorts. Here, we describe an optimised erythrocyte isolation protocol from blood, tested for various storage conditions and explored using different fractionation conditions for isolating ghost RBC membranes. Liquid chromatography mass spectrometry (LC-MS) analysis on a Q-Exactive Orbitrap instrument was used to profile proteins isolated from the comparative conditions. Data analysis was run on the MASCOT and MaxQuant platforms to assess their scope and diversity. The results obtained demonstrate a robust method for membrane enrichment enabling consistent MS based characterisation of > 900 RBC membrane proteins in single LC-MS/MS analyses. Non-detergent based membrane solubilisation methods using the tissue and supernatant fractions of isolated ghost membranes are shown to offer effective haemoglobin removal as well as diverse recovery including erythrocyte membrane proteins of high and low abundance. The methods described in this manuscript propose a medium to high throughput framework for membrane proteome profiling by LC-MS of potential applicability to larger clinical cohorts in a variety of disease contexts.
Detecting local transmission of avian malaria and related haemosporidian parasites (Apicomlexa, Haemosporida) at a Special Protection Area of Natura 2000 network.

PubMed

Dimitrov, Dimitar; Ilieva, Mihaela; Ivanova, Karina; Brlík, Vojtěch; Zehtindjiev, Pavel

2018-05-05

Avian haemosporidian parasites (Apicomplexa, Haemosporida) are widespread pathogens that cause malaria (Plasmodium spp.) and other haemosporidioses (Haemoproteus spp. and Leucocytozoon spp.) in birds. The Special Protection Area Durankulak Lake (SPA DL) is a coastal lake in northeast Bulgaria, part of the Natura 2000 network that was declared as important area for wintering, breeding and migratory birds. Despite a number of conservation efforts outlined for the SPAs of Natura 2000 network, the potential threats and influences of haemosporidians and other parasites on occurring birds were not considered. In the present study, we aim to investigate the richness of haemosporidian parasites in birds captured in the protected area and to report the parasite species/DNA lineages that undergo local transmission in the region. We used both microscopic examination and PCR-based methods to diagnose haemosporidian infections in juvenile (captured in the year of hatching) and adult birds. The overall prevalence of haemosporidian parasites was significantly higher in the adult birds compared to juveniles. We identified five out of 21 recorded cytochrome b (cyt b) parasite lineages that are locally transmitted in the SPA DL (one of the genus Haemoproteus Kruse, 1890 and four of genus Plasmodium Marchiafava and Celli, 1885): cyt b lineages hRW2 of Haemoproteus belopolskyi, pSGS1 of Plasmodium relictum, pCOLL1, pYWT4 and pPADOM01 of Plasmodium (Haemamoeba) spp. It is likely that the majority of the parasites with local transmission are widespread host generalists and that host exchange is rather frequent among the birds inhabiting SPA DL.

A new species of Hepatozoon Miller, 1908 (Apicomplexa: Adelerina) from the snake Philodryas nattereri Steindachner (Squamata: Dipsadidae) in northeastern Brazil.

PubMed

Borges-Nojosa, Diva M; Borges-Leite, M Juliana; Maia, João P; Zanchi-Silva, Djan; da Rocha Braga, Roberta; Harris, D James

2017-01-01

Based on both unique morphological characteristics of the gamont, distinct changes caused to the host erythrocyte and analysis of partial 18S rRNA gene sequences, a new parasite of the genus Hepatozoon Miller, 1908 is described from the snake Philodryas nattereri Steindachner (Squamata: Dipsadidae) in northeastern Brazil. The new species, Hepatozoon musa n. sp., is characterized by large and curved mature gamonts (18.9 ± 0.9 μm in length and 3.8 ± 0.3 μm in width) that considerably engorge infected host erythrocytes and displace the nucleus laterally, which become longer and thinner. Phylogenetic estimates indicate the new species is more closely related to the recently described Hepatozoon cuestensis O'Dwyer, Moço, Paduan, Spenassatto, Silva & Ribolla, 2013, from Brazilian rattlesnakes. These recent findings highlight the need for further studies of Hepatozoon to better determine the biodiversity of this common but poorly-studied parasite group.
A new species of Eimeria (Apicomplexa: Eimeriidae) from tri-colored bats, Perimyotis subflavus (Chiroptera: Vespertilionidae), from the Ouachitas of Arkansas.

PubMed

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.
Gregarines (Apicomplexa, Gregarinasina) in psocids (Insecta, Psocoptera) including a new species description and their potential use as pest control agents.

PubMed

Rueckert, Sonja; Devetak, Dušan

2017-08-01

Gregarine apicomplexans are unicellular organisms that infect invertebrate hosts in marine, freshwater and terrestrial habitats. The largest group of invertebrates infested on land is the insects. The insect order Psocoptera (booklice) has recently gained wider interest due to specimens occurring in stored food products and therefore being considered pest organisms. Biological control agents are often used to eliminate pest organisms. In this study we examined the psocid Dorypteryx domestica, an invasive psocid species that is spreading all over the world. We were able to isolate and describe a new gregarine species (Enterocystis dorypterygis sp. n.) infecting D. domestica. The trophozoites are panduri- or pyriform and their association/syzygy is caudo-frontal. The surface is inscribed by longitudinal epicytic folds covering the complete cell. Phylogenetic analyses of the SSU rDNA gene revealed an only weakly supported relationship with two Gregarina species G. ormieri and G. basiconstrictonea, both from tenebrionid beetles. Gregarines have been proposed to have some potential as biological control agents for several insects. Identifying the gregarine species infecting pest organisms like psocids is a first step and prerequisite for the probable utilization of these parasites as biological control agents in the future. Copyright © 2017 Elsevier GmbH. All rights reserved.
A new species of Monocystis stein, 1848 (Protista: Apicomplexa: Eugregarinida) from the Indian earthworm, Amynthas Hawayanus Rosa, 1891 (Annelida: Oligochaeta).

PubMed

Bandyopadhyay, Probir K; Göçmen, Bayram; Bhowmik, Biplab; Mitra, Amlan Kumar

2006-01-01

As a part of an ongoing biodiversity survey of aseptate gregarine fauna of oligochaete hosts of West Bengal, an expedition was carried out in the Darjeeling district of West Bengal and most of the earthworms collected were found to be infested with a species of Monocystis Stein, 1848. The monocystid species was collected from the seminal vesicles of the earthworm and was identified as a new species, Monocystis amynthae sp. nov. The gamont of the new species is characterized by having an elongated body with broad anterior end, separated from the narrow posterior end by a prominent constriction measuring 49.0-77.0 (66.0+/-1.3) microm x 32.0-41.0 (37.0+/-2.8) microm. The gametocysts are oval-shaped, measuring 40.0-65.0 (58.0+/-2.1) microm. The oocysts are navicular, measuring 8.0-12.0 (10.5+/-1.1) microm x 4.0-6.0 (5.5+/-1.1) microm.
Evaluation of the vector competence of six ixodid tick species for Rangelia vitalii (Apicomplexa, Piroplasmorida), the agent of canine rangeliosis.

PubMed

Soares, João F; Costa, Francisco B; Girotto-Soares, Aline; Da Silva, Aleksandro S; França, Raqueli T; Taniwaki, Sueli A; Dall'Agnol, Bruno; Reck, José; Hagiwara, Mitika K; Labruna, Marcelo B

2018-05-04

Rangelia vitalii is the etiologic agent of canine rangeliosis, a severe piroplasmosis that affects domestic dogs in Brazil, Uruguay and Argentina. While R. vitalii is one of the most pathogenic tick-borne pathogens for dogs in the world, its tick vector has remained unknown. The present study evaluated the vector competence of Rhipicephalus sanguineus sensu lato (both tropical and temperate species), Amblyomma aureolatum, Amblyomma ovale, Amblyomma tigrinum, and Amblyomma sculptum for R. vitalii. These six tick species were selected for the study because they comprise the main tick species infesting dogs within the distribution area of canine rangeliosis in South America. Acquisition feeding of the above six tick species was performed on domestic dogs showing clinical signs of canine rangeliosis, after being experimentally infected through intravenous inoculation or infestation with R. vitalii-infected ticks. Thereafter, engorged ticks were evaluated for transstadial and transovarial passages of R. vitalii through molecular analysis after molting or oviposition and egg hatching. The resultant ticks were evaluated for their competence to transmit R. vitalii to susceptible dogs. Among the six tick species, only A. aureolatum was able to acquire and perpetuate R. vitalii by transstadial and transovarial passages, as demonstrated by >5% infection rates of ticks after hatching or molting. When exposed to transmission feeding, only A. aureolatum ticks were competent to transmit R. vitalii to dogs, which became severely ill, and the results confirmed by molecular methods and blood smear examination to have acquired rangeliosis. Results of the present study, coupled with epidemiological data, indicate that A. aureolatum is a natural vector of R. vitalii. Our results also indicate that R. vitalii is the first Piroplasmorida agent to be transovarially transmitted in Amblyomma ticks. Copyright © 2018 Elsevier GmbH. All rights reserved.
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.

PubMed

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

PubMed

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. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.
Description of three new species of Hepatozoon (Apicomplexa, Hepatozoidae) from Rattlesnakes (Crotalus durissus terrificus) based on molecular, morphometric and morphologic characters.

PubMed

O'Dwyer, Lucia Helena; Moço, Tatiana Cristina; Paduan, Karina dos Santos; Spenassatto, Carine; da Silva, Reinaldo José; Ribolla, Paulo Eduardo Martins

2013-10-01

Hepatozoon spp. are commonly found infecting snakes. Since the latter are parasitized by diverse forms and data in the literature show divergence, we studied Hepatozoon spp. diversity on Crotalus durissus terrificus snakes using both molecular and morphological approaches. Naturally infected animals were employed. Blood was collected, blood smears were prepared and an aliquot was stored at -20°C for DNA extraction. Five specimens of C. durissus terrificus were selected, each of them infected with one gamont type. Morphological and morphometric analyses of the found gamonts led to their grouping into three populations. For molecular characterization, seven oligonucleotide pairs that amplify distinct regions of rDNA gene were tested by adopting the PCR technique. Only the oligonucleotide pairs HepF300/Hep900 and HEMO1/HEMO2 were efficient in amplifying and distinguishing different isolates of Hepatozoon spp. from snakes. The better results were obtained when both oligonucleotide pairs were used in association. Based on the molecular and morphologic differences, three new species were proposed: Hepatozoon cuestensis sp. nov.; Hepatozoon cevapii sp. nov. and Hepatozoon massardii sp. nov. This is the first description of new Hepatozoon species from snakes, based on molecular characterization and morphological data, in South America. Copyright © 2013 Elsevier Inc. All rights reserved.
Four new species of Eimeria (Apicomplexa: Eimeriidae) from Emoia spp. Skinks (Sauria: Scincidae), from Papua New Guinea and the Insular Pacific

USGS Publications Warehouse

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

2017-01-01

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. imparfrom the Cook Islands, Em. loveridgei from PNG, Em. pallidicepsfrom PNG, Em. popei from PNG, and Em. submetallica from PNG. Oocysts of Eimeria stevejayuptoni n. sp. from Em. longicaudawere 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.
Morphological and molecular characterization of Eimeria paludosa coccidian parasite (Apicomplexa:Eimeriidae) in a dusky moorhen (Gallinula tenebrosa, Gould, 1846) in Australia.

PubMed

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. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.
Endogenous Life Cycle of Eimeria melanomytis (Apicomplexa: Eimeriidae) from the Dusky Rice Rat, Melanomys caliginosus (Rodentia: Cricetidae: Sigmodontinae) in Costa Rica.

PubMed

Chinchilla, Misael; Valerio, Idalia; Sánchez, Ronald; Duszynski, Donald W

2017-02-01

Endogenous stages of the life cycle of Eimeria melanomytis, infecting the peripheral epithelial cells of villi of the small intestine of experimentally infected young dusky rice rats, Melanomys caliginosus , were studied. Giemsa-stained mucosal scrapings and histological sections were examined for all the stages. Eimeria melanomytis has 3 generations of meronts (M), different in size, shape, and number of merozoites (m); and in size, shape, and location of the nuclei within the cytoplasm of the meronts. The 3 meront types, M 1 -M 3 , respectively, had 11-14 (m 1 ), 7-10 (m 2 ), and 20-30 (m 3 ) merozoites. Macrogametocytes and microgametocytes, as well as macrogametes and microgametes, complete the sexual cycle forming the unsporulated oocysts. This parasite's endogenous development produced severe intestinal lesions in experimentally infected dusky rice rats.
Four New Species of Eimeria (Apicomplexa: Eimeriidae) from Emoia spp. Skinks (Sauria: Scincidae), from Papua New Guinea and the Insular Pacific.

PubMed

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

PubMed

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

2017-01-01

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.
INTESTINAL LIFE CYCLE OF EIMERIA CALIGINOSA (APICOMPLEXA: EIMERIIDAE) FROM THE DUSKY RICE RAT, MELANOMYS CALIGINOSUS (RODENTIA: CRICETIDAE: SIGMODONTINAE) IN COSTA RICA.

PubMed

Chinchilla, Misael; Valerio, Idalia; Sanchez, Ronald; Duszynski, Donald

2018-05-08

The endogenous life cycle of Eimeria caliginosa was studied in experimentally-infected dusky rice rats, Melanomys caliginosus. All endogenous stages were located in the epithelial cells of villi in the small intestine. Both Giemsa-stained mucosal scrapings and histological sections were studied for the diagnosis of all the life cycle stages. Eimeria caliginosa 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, M1-M3, respectively, had 20-33 (m1), 5-9 (m2), and 13-16 (m3) merozoites. Macrogametocytes and microgametocytes, as well as macrogametes and microgametes, completed the sexual cycle, which conclude with the formation of unsporulated oocysts. This parasite's endogenous development produced severe intestinal lesions in the experimentally-infected dusky rice rats. In our ongoing work to understand the biodiversity present in plants and animals of our protected Reserva Biológica Alberto Manuel Brenes (ReBAMB) field station in Costa Rica, we now have discovered 3 new Eimeria species, and this is the second complete life cycle in which we document both the asexual and sexual stages The presence of Eimeria caliginosa was discovered in Costa Rica, in the dusky rice rat, Melanomys caliginosus (Tomes, 1860), captured in the protected Reserva Biológica Alberto Manuel Brenes (ReBAMB) in San Ramón, Alajuela, Costa Rica (Chinchilla et al. 2014). The original description was based on sporulated oocyst characteristics, but there was no information known about this parasite or its life history at the time of our discovery. Now, using careful experimental protocols, we are able to offer a description of the endogenous stages of the intestinal life cycle of E. caliginosa in M. caliginosus were able to determine the prepatent and patent periods, and we were able to make some observations about the intestinal pathology caused by E. caliginosa in its natural host, the dusky rice rat.
Sarcocystis caninum and Sarcocystis svanai n. spp. (Apicomplexa: Sarcocystidae) associated with severe myositis and hepatitis in the domestic dog (Canis familiaris)

USDA-ARS?s Scientific Manuscript database

Sarcocystis species have a 2-host life cycle with carnivores as definitive hosts and herbivores as intermediate hosts. Occasionally dogs are definitive as well as intermediate hosts for Sarcocystis species. There are several reports of Sarcocystis sarcocysts in muscles of dogs but these species have...
Sarcocystis caninum and Sarcocystis svanai n. spp. (Apicomplexa: Sarcocystidae) Associated with Severe Myositis and Hepatitis in the Domestic Dog (Canis familiaris)

PubMed Central

Dubey, J. P.; Sykes, J. E.; Shelton, G. D.; Sharp, N.; Verma, S. K.; Calero-Bernal, R.; Viviano, J.; Sundar, N.; Khan, A.; Grigg, M. E.

2014-01-01

There are several reports of Sarcocystis sarcocysts in muscles of dogs but these species have not been named. Additionally, there are 2 reports of Sarcocystis neurona in dogs. Here, we propose 2 new names, Sarcocystis caninum, and Sarcocystis svanai for sarcocysts associated with clinical muscular sarcocystosis in 4 domestic dogs (Canis familiaris), 1 each from Montana and Colorado in the USA, and 2 from British Columbia, Canada. Only the sarcocyst stage was identified. Most of the sarcocysts identified were S. caninum. Sarcocysts were studied using light microscopy, transmission electron microscopy, and PCR. Based on collective results 2 new species, Sarcocystis caninum and Sarcocystis svanai were designated. Sarcocystis caninum and Sarcocystis svanai were structurally distinct. Sarcocystis caninum sarcocysts were up to 1.2 mm long and up to 75 μm wide. By light microscopy, the sarcocyst wall was relatively thin and smooth. By transmission electron microscopy (TEM), the sarcocyst wall “type 9”, 1–2 μm thick, and contained villar protrusions that lacked microtubules. Bradyzoites in sections were 7–9 μm long. Sarcocysts of S. svanai were few and were identified by TEM. Sarcocystis svanai sarcocysts were “type 1”, thin walled (< 0.5 μm), and the wall lacked villar protrusions but had tiny blebs that did not invaginate. DNA was extracted either from infected frozen muscle biopsies or formalin-fixed paraffin-embedded sections. Dogs were either singly infected with S. caninum or multiply co-infected with S. caninum and S. svanai (the result of a mixed infection) based on multi-locus DNA sequencing and morphology. BLASTn analysis established that the sarcocysts identified in these dogs were similar to, but not identical to S. canis or S. arctosi, parasites found to infect polar bears (Ursus maritimus) or brown bears (Ursus arctosi), respectively. However, the S. caninum sequence showed 100% identify over the 18S rRNA region sequenced to that of S. arctica, a parasite known to infect Arctic foxes (Vulpes lagopus). PMID:25256157
First description of Cryptosporidium parvum in carrier pigeons (Columba livia).

PubMed

Oliveira, Bruno César Miranda; Ferrari, Elis Domingos; da Cruz Panegossi, Mariele Fernanda; Nakamura, Alex Akira; Corbucci, Flávio Sader; Nagata, Walter Bertequini; Dos Santos, Bianca Martins; Gomes, Jancarlo Ferreira; Meireles, Marcelo Vasconcelos; Widmer, Giovanni; Bresciani, Katia Denise Saraiva

2017-08-30

The carrier pigeon and the domestic pigeon are different breeds of the species Columba livia. Carrier pigeons are used for recreational activities such as bird contests and exhibitions. Due to the close contact with humans, these birds may potentially represent a public health risk, since they can host and disseminate zoonotic parasites, such as those belonging to the genus Cryptosporidium (phylum Apicomplexa). The purpose of this work was the detection by microscopic and molecular techniques of Cryptosporidium spp. oocysts in fecal samples of carrier pigeons, and subsequently to sequence the 18S ribosomal RNA marker of positive samples to identify the species. A total of 100 fecal samples were collected individually in two pigeon breeding facilities from Formiga and Araçatuba, cities located in Minas Gerais state and São Paulo state, Brazil, respectively. The age of the birds ranged from one to 12 years; 56 were females and 44 males. Fecal smears were stained with negative malachite green, whereas the molecular characterization was based on the sequence of a ∼800bp fragment of the 18S rRNA gene. Microscopic examination of fecal smears revealed 4% (4/100) oocyst positivity. On the other hand, 7% (7/100) of positivity were found using nested PCR. Three samples were 99% to 100% similar to Cryptosporidium parvum 18S rDNA type A (Genbank AH006572) and the other three samples had 99% to 100% similarity to C. parvum 18S rDNA type B (Genbank AF308600). To our knowledge, this is the first report of C. parvum oocysts in carrier pigeons. Copyright © 2017 Elsevier B.V. All rights reserved.
Spliced Leader RNAs, Mitochondrial Gene Frameshifts and Multi-Protein Phylogeny Expand Support for the Genus Perkinsus as a Unique Group of Alveolates

PubMed Central

Zhang, Huan; Campbell, David A.; Sturm, Nancy R.; Dungan, Christopher F.; Lin, Senjie

2011-01-01

The genus Perkinsus occupies a precarious phylogenetic position. To gain a better understanding of the relationship between perkinsids, dinoflagellates and other alveolates, we analyzed the nuclear-encoded spliced-leader (SL) RNA and mitochondrial genes, intron prevalence, and multi-protein phylogenies. In contrast to the canonical 22-nt SL found in dinoflagellates (DinoSL), P. marinus has a shorter (21-nt) and a longer (22-nt) SL with slightly different sequences than DinoSL. The major SL RNA transcripts range in size between 80–83 nt in P. marinus, and ∼83 nt in P. chesapeaki, significantly larger than the typical ≤56-nt dinoflagellate SL RNA. In most of the phylogenetic trees based on 41 predicted protein sequences, P. marinus branched at the base of the dinoflagellate clade that included the ancient taxa Oxyrrhis and Amoebophrya, sister to the clade of apicomplexans, and in some cases clustered with apicomplexans as a sister to the dinoflagellate clade. Of 104 Perkinsus spp. genes examined 69.2% had introns, a higher intron prevalence than in dinoflagellates. Examination of Perkinsus spp. mitochondrial cytochrome B and cytochrome C oxidase subunit I genes and their cDNAs revealed no mRNA editing, but these transcripts can only be translated when frameshifts are introduced at every AGG and CCC codon as if AGGY codes for glycine and CCCCU for proline. These results, along with the presence of the numerous uncharacterized ‘marine alveolate group I' and Perkinsus-like lineages separating perkinsids from core dinoflagellates, expand support for the affiliation of the genus Perkinsus with an independent lineage (Perkinsozoa) positioned between the phyla of Apicomplexa and Dinoflagellata. PMID:21629701
Morphological and molecular characterization of Karyolysus--a neglected but common parasite infecting some European lizards.

PubMed

Haklová-Kočíková, Božena; Hižňanová, Adriana; Majláth, Igor; Račka, Karol; Harris, David James; Földvári, Gábor; Tryjanowski, Piotr; Kokošová, Natália; Malčeková, Beáta; Majláthová, Viktória

2014-12-10

Blood parasites of the genus Karyolysus Labbé, 1894 (Apicomplexa: Adeleida: Karyolysidae) represent the protozoan haemogregarines found in various genera of lizards, including Lacerta, Podarcis, Darevskia (Lacertidae) and Mabouia (Scincidae). The vectors of parasites are gamasid mites from the genus Ophionyssus. A total of 557 individuals of lacertid lizards were captured in four different localities in Europe (Hungary, Poland, Romania and Slovakia) and blood was collected. Samples were examined using both microscopic and molecular methods, and phylogenetic relationships of all isolates of Karyolysus sp. were assessed for the first time. Karyolysus sp. 18S rRNA isolates were evaluated using Bayesian and Maximum Likelihood analyses. A total of 520 blood smears were examined microscopically and unicellular protozoan parasites were found in 116 samples (22.3% prevalence). The presence of two Karyolysus species, K. latus and K. lacazei was identified. In total, of 210 samples tested by polymerase chain reaction (PCR), the presence of parasites was observed in 64 individuals (prevalence 30.5%). Results of phylogenetic analyses revealed the existence of four haplotypes, all part of the same lineage, with other parasites identified as belonging to the genus Hepatozoon. Classification of these parasites using current taxonomy is complex - they were identified in both mites and ticks that typically are considered to host Karyolysus and Hepatozoon respectively. Furthermore although distortions to the intermediate host erythrocyte nuclei were observed, the defining characteristic of Karyolysus, the haplotypes were nearly identical to those reported from lizards in the Iberian Peninsula, where such distortions were not reported and which were thus identified as Hepatozoon. Based on the phylogenetic analyses, neither vertebrate host, nor geographical patterns of the studied blood parasites could be established.
Identification of candidate transmission-blocking antigen genes in Theileria annulata and related vector-borne apicomplexan parasites.

PubMed

Lempereur, Laetitia; Larcombe, Stephen D; Durrani, Zeeshan; Karagenc, Tulin; Bilgic, Huseyin Bilgin; Bakirci, Serkan; Hacilarlioglu, Selin; Kinnaird, Jane; Thompson, Joanne; Weir, William; Shiels, Brian

2017-06-05

Vector-borne apicomplexan parasites are a major cause of mortality and morbidity to humans and livestock globally. The most important disease syndromes caused by these parasites are malaria, babesiosis and theileriosis. Strategies for control often target parasite stages in the mammalian host that cause disease, but this can result in reservoir infections that promote pathogen transmission and generate economic loss. Optimal control strategies should protect against clinical disease, block transmission and be applicable across related genera of parasites. We have used bioinformatics and transcriptomics to screen for transmission-blocking candidate antigens in the tick-borne apicomplexan parasite, Theileria annulata. A number of candidate antigen genes were identified which encoded amino acid domains that are conserved across vector-borne Apicomplexa (Babesia, Plasmodium and Theileria), including the Pfs48/45 6-cys domain and a novel cysteine-rich domain. Expression profiling confirmed that selected candidate genes are expressed by life cycle stages within infected ticks. Additionally, putative B cell epitopes were identified in the T. annulata gene sequences encoding the 6-cys and cysteine rich domains, in a gene encoding a putative papain-family cysteine peptidase, with similarity to the Plasmodium SERA family, and the gene encoding the T. annulata major merozoite/piroplasm surface antigen, Tams1. Candidate genes were identified that encode proteins with similarity to known transmission blocking candidates in related parasites, while one is a novel candidate conserved across vector-borne apicomplexans and has a potential role in the sexual phase of the life cycle. The results indicate that a 'One Health' approach could be utilised to develop a transmission-blocking strategy effective against vector-borne apicomplexan parasites of animals and humans.

Sarcocystis neurona Merozoites Express a Family of Immunogenic Surface Antigens That Are Orthologues of the Toxoplasma gondii Surface Antigens (SAGs) and SAG-Related Sequences†

PubMed Central

Howe, Daniel K.; Gaji, Rajshekhar Y.; Mroz-Barrett, Meaghan; Gubbels, Marc-Jan; Striepen, Boris; Stamper, Shelby

2005-01-01

Sarcocystis neurona is a member of the Apicomplexa that causes myelitis and encephalitis in horses but normally cycles between the opossum and small mammals. Analysis of an S. neurona expressed sequence tag (EST) database revealed four paralogous proteins that exhibit clear homology to the family of surface antigens (SAGs) and SAG-related sequences of Toxoplasma gondii. The primary peptide sequences of the S. neurona proteins are consistent with the two-domain structure that has been described for the T. gondii SAGs, and each was predicted to have an amino-terminal signal peptide and a carboxyl-terminal glycolipid anchor addition site, suggesting surface localization. All four proteins were confirmed to be membrane associated and displayed on the surface of S. neurona merozoites. Due to their surface localization and homology to T. gondii surface antigens, these S. neurona proteins were designated SnSAG1, SnSAG2, SnSAG3, and SnSAG4. Consistent with their homology, the SnSAGs elicited a robust immune response in infected and immunized animals, and their conserved structure further suggests that the SnSAGs similarly serve as adhesins for attachment to host cells. Whether the S. neurona SAG family is as extensive as the T. gondii SAG family remains unresolved, but it is probable that additional SnSAGs will be revealed as more S. neurona ESTs are generated. The existence of an SnSAG family in S. neurona indicates that expression of multiple related surface antigens is not unique to the ubiquitous organism T. gondii. Instead, the SAG gene family is a common trait that presumably has an essential, conserved function(s). PMID:15664946
Sarcocystis neurona merozoites express a family of immunogenic surface antigens that are orthologues of the Toxoplasma gondii surface antigens (SAGs) and SAG-related sequences.

PubMed

Howe, Daniel K; Gaji, Rajshekhar Y; Mroz-Barrett, Meaghan; Gubbels, Marc-Jan; Striepen, Boris; Stamper, Shelby

2005-02-01

Sarcocystis neurona is a member of the Apicomplexa that causes myelitis and encephalitis in horses but normally cycles between the opossum and small mammals. Analysis of an S. neurona expressed sequence tag (EST) database revealed four paralogous proteins that exhibit clear homology to the family of surface antigens (SAGs) and SAG-related sequences of Toxoplasma gondii. The primary peptide sequences of the S. neurona proteins are consistent with the two-domain structure that has been described for the T. gondii SAGs, and each was predicted to have an amino-terminal signal peptide and a carboxyl-terminal glycolipid anchor addition site, suggesting surface localization. All four proteins were confirmed to be membrane associated and displayed on the surface of S. neurona merozoites. Due to their surface localization and homology to T. gondii surface antigens, these S. neurona proteins were designated SnSAG1, SnSAG2, SnSAG3, and SnSAG4. Consistent with their homology, the SnSAGs elicited a robust immune response in infected and immunized animals, and their conserved structure further suggests that the SnSAGs similarly serve as adhesins for attachment to host cells. Whether the S. neurona SAG family is as extensive as the T. gondii SAG family remains unresolved, but it is probable that additional SnSAGs will be revealed as more S. neurona ESTs are generated. The existence of an SnSAG family in S. neurona indicates that expression of multiple related surface antigens is not unique to the ubiquitous organism T. gondii. Instead, the SAG gene family is a common trait that presumably has an essential, conserved function(s).
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

PubMed Central

Kumar, Rajinder; Adams, Brian; Oldenburg, Anja; Musiyenko, Alla; Barik, Sailen

2002-01-01

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. PMID:12057017
Dissecting the interface between apicomplexan parasite and host cell: Insights from a divergent AMA–RON2 pair

PubMed Central

Parker, Michelle L.; Penarete-Vargas, Diana M.; Hamilton, Phineas T.; Guérin, Amandine; Dubey, Jitender P.; Perlman, Steve J.; Spano, Furio; Lebrun, Maryse; Boulanger, Martin J.

2016-01-01

Plasmodium falciparum and Toxoplasma gondii are widely studied parasites in phylum Apicomplexa and the etiological agents of severe human malaria and toxoplasmosis, respectively. These intracellular pathogens have evolved a sophisticated invasion strategy that relies on delivery of proteins into the host cell, where parasite-derived rhoptry neck protein 2 (RON2) family members localize to the host outer membrane and serve as ligands for apical membrane antigen (AMA) family surface proteins displayed on the parasite. Recently, we showed that T. gondii harbors a novel AMA designated as TgAMA4 that shows extreme sequence divergence from all characterized AMA family members. Here we show that sporozoite-expressed TgAMA4 clusters in a distinct phylogenetic clade with Plasmodium merozoite apical erythrocyte-binding ligand (MAEBL) proteins and forms a high-affinity, functional complex with its coevolved partner, TgRON2L1. High-resolution crystal structures of TgAMA4 in the apo and TgRON2L1-bound forms complemented with alanine scanning mutagenesis data reveal an unexpected architecture and assembly mechanism relative to previously characterized AMA–RON2 complexes. Principally, TgAMA4 lacks both a deep surface groove and a key surface loop that have been established to govern RON2 ligand binding selectivity in other AMAs. Our study reveals a previously underappreciated level of molecular diversity at the parasite–host-cell interface and offers intriguing insight into the adaptation strategies underlying sporozoite invasion. Moreover, our data offer the potential for improved design of neutralizing therapeutics targeting a broad range of AMA–RON2 pairs and apicomplexan invasive stages. PMID:26712012
Multiple essential functions of Plasmodium falciparum actin-1 during malaria blood-stage development.

PubMed

Das, Sujaan; Lemgruber, Leandro; Tay, Chwen L; Baum, Jake; Meissner, Markus

2017-08-15

The phylum Apicomplexa includes intracellular parasites causing immense global disease burden, the deadliest of them being the human malaria parasite Plasmodium falciparum, which invades and replicates within erythrocytes. The cytoskeletal protein actin is well conserved within apicomplexans but divergent from mammalian actins, and was primarily reported to function during host cell invasion. However, novel invasion mechanisms have been described for several apicomplexans, and specific functions of the acto-myosin system are being reinvestigated. Of the two actin genes in P. falciparum, actin-1 (pfact1) is ubiquitously expressed in all life-cycle stages and is thought to be required for erythrocyte invasion, although its functions during parasite development are unknown, and definitive in vivo characterisation during invasion is lacking. Here we have used a conditional Cre-lox system to investigate the functions of PfACT1 during P. falciparum blood-stage development and host cell invasion. We demonstrate that PfACT1 is crucially required for segregation of the plastid-like organelle, the apicoplast, and for efficient daughter cell separation during the final stages of cytokinesis. Surprisingly, we observe that egress from the host cell is not an actin-dependent process. Finally, we show that parasites lacking PfACT1 are capable of microneme secretion, attachment and formation of a junction with the erythrocyte, but are incapable of host cell invasion. This study provides important mechanistic insights into the definitive essential functions of PfACT1 in P. falciparum, which are not only of biological interest, but owing to functional divergence from mammalian actins, could also form the basis for the development of novel therapeutics against apicomplexans.
Cryptic Eimeria genotypes are common across the southern but not northern hemisphere.

PubMed

Clark, Emily L; Macdonald, Sarah E; Thenmozhi, V; Kundu, Krishnendu; Garg, Rajat; Kumar, Saroj; Ayoade, Simeon; Fornace, Kimberly M; Jatau, Isa Danladi; Moftah, Abdalgader; Nolan, Matthew J; Sudhakar, N R; Adebambo, A O; Lawal, I A; Álvarez Zapata, Ramón; Awuni, Joseph A; Chapman, H David; Karimuribo, Esron; Mugasa, Claire M; Namangala, Boniface; Rushton, Jonathan; Suo, Xun; Thangaraj, Kumarasamy; Srinivasa Rao, Arni S R; Tewari, Anup K; Banerjee, Partha S; Dhinakar Raj, G; Raman, M; Tomley, Fiona M; Blake, Damer P

2016-08-01

The phylum Apicomplexa includes parasites of medical, zoonotic and veterinary significance. Understanding the global distribution and genetic diversity of these protozoa is of fundamental importance for efficient, robust and long-lasting methods of control. Eimeria spp. cause intestinal coccidiosis in all major livestock animals and are the most important parasites of domestic chickens in terms of both economic impact and animal welfare. Despite having significant negative impacts on the efficiency of food production, many fundamental questions relating to the global distribution and genetic variation of Eimeria spp. remain largely unanswered. Here, we provide the broadest map yet of Eimeria occurrence for domestic chickens, confirming that all the known species (Eimeria acervulina, Eimeria brunetti, Eimeria maxima, Eimeria mitis, Eimeria necatrix, Eimeria praecox, Eimeria tenella) are present in all six continents where chickens are found (including 21 countries). Analysis of 248 internal transcribed spacer sequences derived from 17 countries provided evidence of possible allopatric diversity for species such as E. tenella (FST values ⩽0.34) but not E. acervulina and E. mitis, and highlighted a trend towards widespread genetic variance. We found that three genetic variants described previously only in Australia and southern Africa (operational taxonomic units x, y and z) have a wide distribution across the southern, but not the northern hemisphere. While the drivers for such a polarised distribution of these operational taxonomic unit genotypes remains unclear, the occurrence of genetically variant Eimeria may pose a risk to food security and animal welfare in Europe and North America should these parasites spread to the northern hemisphere. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.
Immune response in the adipose tissue of lean mice infected with the protozoan parasite Neospora caninum

PubMed Central

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

2015-01-01

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. PMID:25581844
A linear mitochondrial genome of Cyclospora cayetanensis (Eimeriidae, Eucoccidiorida, Coccidiasina, Apicomplexa) suggests the ancestral start position within mitochondrial genomes of eimeriid coccidia.

PubMed

Ogedengbe, Mosun E; Qvarnstrom, Yvonne; da Silva, Alexandre J; Arrowood, Michael J; Barta, John R

2015-05-01

The near complete mitochondrial genome for Cyclospora cayetanensis is 6184 bp in length with three protein-coding genes (Cox1, Cox3, CytB) and numerous lsrDNA and ssrDNA fragments. Gene arrangements were conserved with other coccidia in the Eimeriidae, but the C. cayetanensis mitochondrial genome is not circular-mapping. Terminal transferase tailing and nested PCR completed the 5'-terminus of the genome starting with a 21 bp A/T-only region that forms a potential stem-loop. Regions homologous to the C. cayetanensis mitochondrial genome 5'-terminus are found in all eimeriid mitochondrial genomes available and suggest this may be the ancestral start of eimeriid mitochondrial genomes. Copyright © 2015 Australian Society for Parasitology Inc. All rights reserved.
A Comparison of Multiple Methods for Estimating Parasitemia of Hemogregarine Hemoparasites (Apicomplexa: Adeleorina) and Its Application for Studying Infection in Natural Populations

PubMed Central

Maia, João P.; Harris, D. James; Carranza, Salvador; Gómez-Díaz, Elena

2014-01-01

Identifying factors influencing infection patterns among hosts is critical for our understanding of the evolution and impact of parasitism in natural populations. However, the correct estimation of infection parameters depends on the performance of detection and quantification methods. In this study, we designed a quantitative PCR (qPCR) assay targeting the 18 S rRNA gene to estimate prevalence and intensity of Hepatozoon infection and compared its performance with microscopy and PCR. Using qPCR, we also compared various protocols that differ in the biological source and the extraction methods. Our results show that the qPCR approach on DNA extracted from blood samples, regardless of the extraction protocol, provided the most sensitive estimates of Hepatozoon infection parameters; while allowed us to differentiate between mixed infections of Adeleorinid (Hepatozoon) and Eimeriorinid (Schellackia and Lankesterella), based on the analysis of melting curves. We also show that tissue and saline methods can be used as low-cost alternatives in parasitological studies. The next step was to test our qPCR assay in a biological context, and for this purpose we investigated infection patterns between two sympatric lacertid species, which are naturally infected with apicomplexan hemoparasites, such as the genera Schellackia (Eimeriorina) and Hepatozoon (Adeleorina). From a biological standpoint, we found a positive correlation between Hepatozoon intensity of infection and host body size within each host species, being significantly higher in males, and higher in the smaller sized host species. These variations can be associated with a number of host intrinsic factors, like hormonal and immunological traits, that require further investigation. Our findings are relevant as they pinpoint the importance of accounting for methodological issues to better estimate infection in parasitological studies, and illustrate how between-host factors can influence parasite distributions in sympatric natural populations. PMID:24743340
First molecular characterization of a Hepatozoon species (Apicomplexa: Hepatozoidae) infecting birds and description of a new species infecting storm petrels (Aves: Hydrobatidae).

PubMed

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.
Intestinal coccidiosis of anadromous and landlocked alewives, Alosa pseudoharengus, caused by Goussia ameliae n. sp. and G. alosii n. sp. (Apicomplexa: Eimeriidae)

PubMed Central

Lovy, Jan; Friend, Sarah E.

2015-01-01

Anadromous alewives, Alosa pseudoharengus, have experienced significant population level declines caused by factors including habitat destruction. Alewives occur in two different life histories, anadromous and landlocked forms. The landlocked alewife evolved from ancestral anadromous populations, resulting in an exclusively freshwater and phenotypically unique form. The occurrence of parasites in a host is linked to the environment, making alewives an ideal model to compare parasitology within a single species with contrasting life histories. Currently, little information exists on the presence and impacts of parasites in these fish populations; the present study sets out to better understand coccidiosis in the threatened anadromous populations and to understand how coccidian parasites compare in both life history forms. The intestinal coccidian, Goussia ameliae n. sp., was described infecting the pyloric cecum of 76% and 86% of young-of-the-year and adult anadromous alewives, respectively, from the Maurice River, New Jersey, USA. The coccidian was found in landlocked alewife populations with a prevalence of 92% and 34% in YOY and adult fish, respectively. An analysis of the small subunit 18S ribosomal RNA gene of G. ameliae from both life history forms demonstrated that the coccidian had 100% sequence identity, confirming the same parasite species in both forms. Though genetic analysis demonstrated G. ameliae to be identical, some differences were observed in sporulation and morphology of the parasite within the two populations. The sporocysts in anadromous populations were shorter and wider, and sporulation timing differed from that of landlocked fish. These differences may either be attributed to differences in the host type or to the sporulation environment. Lastly, alewives from landlocked populations were frequently co-infected with a second coccidian species in the posterior intestine, which occurred at a lower prevalence. This species, G. alosii n. sp., was described based on morphological characters of the sporulated oocysts in fresh parasitological preparations. PMID:25853050
Sarcocystis masoni, n. sp. (Apicomplexa: Sarcocystidae), and redescription of Sarcocystis aucheniae from llama (Lama glama), guanaco (Lama guanicoe) and alpaca (Vicugna pacos)

USDA-ARS?s Scientific Manuscript database

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 name the...
A comparison of multiple methods for estimating parasitemia of hemogregarine hemoparasites (apicomplexa: adeleorina) and its application for studying infection in natural populations.

PubMed

Maia, João P; Harris, D James; Carranza, Salvador; Gómez-Díaz, Elena

2014-01-01

Identifying factors influencing infection patterns among hosts is critical for our understanding of the evolution and impact of parasitism in natural populations. However, the correct estimation of infection parameters depends on the performance of detection and quantification methods. In this study, we designed a quantitative PCR (qPCR) assay targeting the 18 S rRNA gene to estimate prevalence and intensity of Hepatozoon infection and compared its performance with microscopy and PCR. Using qPCR, we also compared various protocols that differ in the biological source and the extraction methods. Our results show that the qPCR approach on DNA extracted from blood samples, regardless of the extraction protocol, provided the most sensitive estimates of Hepatozoon infection parameters; while allowed us to differentiate between mixed infections of Adeleorinid (Hepatozoon) and Eimeriorinid (Schellackia and Lankesterella), based on the analysis of melting curves. We also show that tissue and saline methods can be used as low-cost alternatives in parasitological studies. The next step was to test our qPCR assay in a biological context, and for this purpose we investigated infection patterns between two sympatric lacertid species, which are naturally infected with apicomplexan hemoparasites, such as the genera Schellackia (Eimeriorina) and Hepatozoon (Adeleorina). From a biological standpoint, we found a positive correlation between Hepatozoon intensity of infection and host body size within each host species, being significantly higher in males, and higher in the smaller sized host species. These variations can be associated with a number of host intrinsic factors, like hormonal and immunological traits, that require further investigation. Our findings are relevant as they pinpoint the importance of accounting for methodological issues to better estimate infection in parasitological studies, and illustrate how between-host factors can influence parasite distributions in sympatric natural populations.
New data on Eimeria dicentrarchi (Apicomplexa: Eimeriidae), a common parasite of farmed European sea bass (Dicentrarchus labrax) from the mid-eastern Adriatic

USDA-ARS?s Scientific Manuscript database

This study extends the original description of Eimeria dicentrarchi Daoudi and Marquès, 1987, a common coccidian parasite of European sea bass from the mid-eastern Adriatic, by providing insights into the parasite’s site of infection, development and pathogenicity. E. dicentrarchi was found in vario...
Two COWP-like cysteine rich proteins from Eimeria nieschulzi (coccidia, apicomplexa) are expressed during sporulation and involved in the sporocyst wall formation.

PubMed

Jonscher, Ernst; Erdbeer, Alexander; Günther, Marie; Kurth, Michael

2015-07-25

The family of cysteine rich proteins of the oocyst wall (COWPs) originally described in Cryptosporidium can also be found in Toxoplasma gondii (TgOWPs) localised to the oocyst wall as well. Genome sequence analysis of Eimeria suggests that these proteins may also exist in this genus and led us to the assumption that these proteins may also play a role in oocyst wall formation. In this study, COWP-like encoding sequences had been identified in Eimeria nieschulzi. The predicted gene sequences were subsequently utilized in reporter gene assays to observe time of expression and localisation of the reporter protein in vivo. Both investigated proteins, EnOWP2 and EnOWP6, were expressed during sporulation. The EnOWP2-promoter driven mCherry was found in the cytoplasm and the EnOWP2, respectively EnOWP6, fused to mCherry was initially observed in the extracytoplasmatic space between sporoblast and oocyst wall. This, so far unnamed compartment was designated as circumplasm. Later, the mCherry reporter co-localised with the sporocyst wall of the sporulated oocysts. This observation had been confirmed by confocal microscopy, excystation experiments and IFA. Transcript analysis revealed the intron-exon structure of these genes and confirmed the expression of EnOWP2 and EnOWP6 during sporogony. Our results allow us to assume a role, of both investigated EnOWP proteins, in the sporocyst wall formation of E. nieschulzi. Data mining and sequence comparisons to T. gondii and other Eimeria species allow us to hypothesise a conserved process within the coccidia. A role in oocyst wall formation had not been observed in E. nieschulzi.
Two new species of Eimeria (Apicomplexa: Eimeriidae) from emerald tree skinks, Lamprolepis smaragdina (Sauria: Scincidae) from Papua New Guinea and the Philippines

PubMed Central

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

2014-01-01

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 sp. n. from the only L. smaragdina from PNG are ovoidal, with a smooth, colourless, bilayered 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 2 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 sp. n. from both L. smaragdina we collected in the Philippines are ovoidal, with a smooth, colorless, bilayered wall, measure 19.9 × 15.8 μm, L/W 1.3; both micropyle and oöcyst residuum are absent, but 1–4 polar granules are present. Sporocysts are ovoidal to ellipsoidal, 10.3 × 5.8 μm, L/W 1.8, and the wall is composed of 2 valves joined by a longitudinal suture; neither Stieda nor sub-Stieda bodies are present; a sporocyst residuum is composed of dispersed granules. PMID:24048748
Sarcocystis masoni, n. sp. (Apicomplexa: Sarcocystidae), and redescription of Sarcocystis aucheniae from llama (Lama glama), guanaco (Lama guanicoe) and alpaca (Vicugna pacos).

PubMed

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

PubMed

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.
Deciphering the ubiquitin-mediated pathway in apicomplexan parasites: a potential strategy to interfere with parasite virulence.

PubMed

Ponts, Nadia; Yang, Jianfeng; Chung, Duk-Won Doug; Prudhomme, Jacques; Girke, Thomas; Horrocks, Paul; Le Roch, Karine G

2008-06-11

Reversible modification of proteins through the attachment of ubiquitin or ubiquitin-like modifiers is an essential post-translational regulatory mechanism in eukaryotes. The conjugation of ubiquitin or ubiquitin-like proteins has been demonstrated to play roles in growth, adaptation and homeostasis in all eukaryotes, with perturbation of ubiquitin-mediated systems associated with the pathogenesis of many human diseases, including cancer and neurodegenerative disorders. Here we describe the use of an HMM search of functional Pfam domains found in the key components of the ubiquitin-mediated pathway necessary to activate and reversibly modify target proteins in eight apicomplexan parasitic protozoa for which complete or late-stage genome projects exist. In parallel, the same search was conducted on five model organisms, single-celled and metazoans, to generate data to validate both the search parameters employed and aid paralog classification in Apicomplexa. For each of the 13 species investigated, a set of proteins predicted to be involved in the ubiquitylation pathway has been identified and demonstrates increasing component members of the ubiquitylation pathway correlating with organism and genome complexity. Sequence homology and domain architecture analyses facilitated prediction of apicomplexan-specific protein function, particularly those involved in regulating cell division during these parasite's complex life cycles. This study provides a comprehensive analysis of proteins predicted to be involved in the apicomplexan ubiquitin-mediated pathway. Given the importance of such pathway in a wide variety of cellular processes, our data is a key step in elucidating the biological networks that, in part, direct the pathogenicity of these parasites resulting in a massive impact on global health. Moreover, apicomplexan-specific adaptations of the ubiquitylation pathway may represent new therapeutic targets for much needed drugs against apicomplexan parasites.
Basal body structure and composition in the apicomplexans Toxoplasma and Plasmodium.

PubMed

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

Time-Lapse Video Microscopy of Gliding Motility in Toxoplasma gondii Reveals a Novel, Biphasic Mechanism of Cell LocomotionV⃞

PubMed Central

Håkansson, Sebastian; Morisaki, Hiroshi; Heuser, John; Sibley, L. David

1999-01-01

Toxoplasma gondii is a member of the phylum Apicomplexa, a diverse group of intracellular parasites that share a unique form of gliding motility. Gliding is substrate dependent and occurs without apparent changes in cell shape and in the absence of traditional locomotory organelles. Here, we demonstrate that gliding is characterized by three distinct forms of motility: circular gliding, upright twirling, and helical rotation. Circular gliding commences while the crescent-shaped parasite lies on its right side, from where it moves in a counterclockwise manner at a rate of ∼1.5 μm/s. Twirling occurs when the parasite rights itself vertically, remaining attached to the substrate by its posterior end and spinning clockwise. Helical gliding is similar to twirling except that it occurs while the parasite is positioned horizontally, resulting in forward movement that follows the path of a corkscrew. The parasite begins lying on its left side (where the convex side is defined as dorsal) and initiates a clockwise revolution along the long axis of the crescent-shaped body. Time-lapse video analyses indicated that helical gliding is a biphasic process. During the first 180o of the turn, the parasite moves forward one body length at a rate of ∼1–3 μm/s. In the second phase, the parasite flips onto its left side, in the process undergoing little net forward motion. All three forms of motility were disrupted by inhibitors of actin filaments (cytochalasin D) and myosin ATPase (butanedione monoxime), indicating that they rely on an actinomyosin motor in the parasite. Gliding motility likely provides the force for active penetration of the host cell and may participate in dissemination within the host and thus is of both fundamental and practical interest. PMID:10564254
Structural and Functional Divergence of the Aldolase Fold in Toxoplasma gondii

DOE PAGES

Tonkin, Michelle L.; Halavaty, Andrei S.; Ramaswamy, Raghavendran; ...

2014-10-02

Parasites of the phylum Apicomplexa are highly successful pathogens of humans and animals worldwide. As obligate intracellular parasites, they have significant energy requirements for invasion and gliding motility that are supplied by various metabolic pathways. Aldolases have emerged as key enzymes involved in these pathways, and all apicomplexans express one or both of fructose 1,6-bisphosphate (F16BP) aldolase and 2-deoxyribose 5-phosphate (dR5P) aldolase (DERA). Intriguingly, Toxoplasma gondii, a highly successful apicomplexan parasite, expresses F16BP aldolase (TgALD1), d5RP aldolase (TgDERA), and a divergent dR5P aldolase-like protein (TgDPA) exclusively in the latent bradyzoite stage. While the importance of TgALD1 in glycolysis is wellmore » established and TgDERA is also likely to be involved in parasite metabolism, the detailed function of TgDPA remains elusive. Here, to gain mechanistic insight into the function of different T. gondii aldolases, we first determined the crystal structures of TgALD1 and TgDPA. Structural analysis revealed that both aldolases adopt a TIM barrel fold accessorized with divergent secondary structure elements. Structural comparison of TgALD1 and TgDPA with members of their respective enzyme families revealed that, while the active-site residues are conserved in TgALD1, key catalytic residues are absent in TgDPA. Consistent with this observation, biochemical assays showed that, while TgALD1 was active on F16BP, TgDPA was inactive on dR5P. In conclusion, intriguingly, both aldolases are competent to bind polymerized actin in vitro. Altogether, structural and biochemical analyses of T. gondii aldolase and aldolase-like proteins reveal diverse functionalization of the classic TIM barrel aldolase fold.« less
Discovery of a Splicing Regulator Required for Cell Cycle Progression

DOE Office of Scientific and Technical Information (OSTI.GOV)

Suvorova, Elena S.; Croken, Matthew; Kratzer, Stella

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 amore » 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.« less
A review of the infection, genetics, and evolution of Neospora caninum: from the past to the present.

PubMed

Goodswen, Stephen J; Kennedy, Paul J; Ellis, John T

2013-01-01

This paper is a review of current knowledge on Neospora caninum in the context of other apicomplexan parasites and with an emphasis on: life cycle, disease, epidemiology, immunity, control and treatment, evolution, genomes, and biological databases and web resources. N. caninum is an obligate, intracellular, coccidian, protozoan parasite of the phylum Apicomplexa. Infection can cause the clinical disease neosporosis, which most notably is associated with abortion in cattle. These abortions are a major root cause of economic loss to both the dairy and beef industries worldwide. N. caninum has been detected in every country in which a study has been specifically conducted to detect this parasite in cattle. The major mode of transmission in cattle is transplacental (or vertical) transmission and several elements of the N. caninum life cycle are yet to be studied in detail. The outcome of an infection is inextricably linked to the precise timing of the infection coupled with the status of the immune system of the dam and foetus. There is no community consensus as to whether it is the dam's pro-inflammatory cytotoxic response to tachyzoites that kills the foetus or the tachyzoites themselves. From economic analysis the most cost-effective approach to control neosporosis is a vaccine. The perfect vaccine would protect against both infection and the clinical disease, and this implies a vaccine is needed that can induce a non-foetopathic cell mediated immunity response. Researchers are beginning to capitalise on the vast potential of -omics data (e.g. genomes, transcriptomes, and proteomes) to further our understanding of pathogens but especially to identify vaccine and drug targets. The recent publication of a genome for N. caninum offers vast opportunities in these areas. Copyright © 2012 Elsevier B.V. All rights reserved.
Pilot survey of expressed sequence tags (ESTs) from the asexual blood stages of Plasmodium vivax in human patients.

PubMed

Merino, Emilio F; Fernandez-Becerra, Carmen; Madeira, Alda M B N; Machado, Ariane L; Durham, Alan; Gruber, Arthur; Hall, Neil; del Portillo, Hernando A

2003-07-21

Plasmodium vivax is the most widely distributed human malaria, responsible for 70-80 million clinical cases each year and large socio-economical burdens for countries such as Brazil where it is the most prevalent species. Unfortunately, due to the impossibility of growing this parasite in continuous in vitro culture, research on P. vivax remains largely neglected. A pilot survey of expressed sequence tags (ESTs) from the asexual blood stages of P. vivax was performed. To do so, 1,184 clones from a cDNA library constructed with parasites obtained from 10 different human patients in the Brazilian Amazon were sequenced. Sequences were automatedly processed to remove contaminants and low quality reads. A total of 806 sequences with an average length of 586 bp met such criteria and their clustering revealed 666 distinct events. The consensus sequence of each cluster and the unique sequences of the singlets were used in similarity searches against different databases that included P. vivax, Plasmodium falciparum, Plasmodium yoelii, Plasmodium knowlesi, Apicomplexa and the GenBank non-redundant database. An E-value of <10(-30) was used to define a significant database match. ESTs were manually assigned a gene ontology (GO) terminology A total of 769 ESTs could be assigned a putative identity based upon sequence similarity to known proteins in GenBank. Moreover, 292 ESTs were annotated and a GO terminology was assigned to 164 of them. These are the first ESTs reported for P. vivax and, as such, they represent a valuable resource to assist in the annotation of the P. vivax genome currently being sequenced. Moreover, since the GC-content of the P. vivax genome is strikingly different from that of P. falciparum, these ESTs will help in the validation of gene predictions for P. vivax and to create a gene index of this malaria parasite.
Comparative Bioinformatics Analysis of Transcription Factor Genes Indicates Conservation of Key Regulatory Domains among Babesia bovis, Babesia microti, and Theileria equi.

PubMed

Alzan, Heba F; Knowles, Donald P; Suarez, Carlos E

2016-11-01

Apicomplexa tick-borne hemoparasites, including Babesia bovis, Babesia microti, and Theileria equi are responsible for bovine and human babesiosis and equine theileriosis, respectively. These parasites of vast medical, epidemiological, and economic impact have complex life cycles in their vertebrate and tick hosts. Large gaps in knowledge concerning the mechanisms used by these parasites for gene regulation remain. Regulatory genes coding for DNA binding proteins such as members of the Api-AP2, HMG, and Myb families are known to play crucial roles as transcription factors. Although the repertoire of Api-AP2 has been defined and a HMG gene was previously identified in the B. bovis genome, these regulatory genes have not been described in detail in B. microti and T. equi. In this study, comparative bioinformatics was used to: (i) identify and map genes encoding for these transcription factors among three parasites' genomes; (ii) identify a previously unreported HMG gene in B. microti; (iii) define a repertoire of eight conserved Myb genes; and (iv) identify AP2 correlates among B. bovis and the better-studied Plasmodium parasites. Searching the available transcriptome of B. bovis defined patterns of transcription of these three gene families in B. bovis erythrocyte stage parasites. Sequence comparisons show conservation of functional domains and general architecture in the AP2, Myb, and HMG proteins, which may be significant for the regulation of common critical parasite life cycle transitions in B. bovis, B. microti, and T. equi. A detailed understanding of the role of gene families encoding DNA binding proteins will provide new tools for unraveling regulatory mechanisms involved in B. bovis, B. microti, and T. equi life cycles and environmental adaptive responses and potentially contributes to the development of novel convergent strategies for improved control of babesiosis and equine piroplasmosis.
Structural and functional divergence of the aldolase fold in Toxoplasma gondii.

PubMed

Tonkin, Michelle L; Halavaty, Andrei S; Ramaswamy, Raghavendran; Ruan, Jiapeng; Igarashi, Makoto; Ngô, Huân M; Boulanger, Martin J

2015-02-27

Parasites of the phylum Apicomplexa are highly successful pathogens of humans and animals worldwide. As obligate intracellular parasites, they have significant energy requirements for invasion and gliding motility that are supplied by various metabolic pathways. Aldolases have emerged as key enzymes involved in these pathways, and all apicomplexans express one or both of fructose 1,6-bisphosphate (F16BP) aldolase and 2-deoxyribose 5-phosphate (dR5P) aldolase (DERA). Intriguingly, Toxoplasma gondii, a highly successful apicomplexan parasite, expresses F16BP aldolase (TgALD1), d5RP aldolase (TgDERA), and a divergent dR5P aldolase-like protein (TgDPA) exclusively in the latent bradyzoite stage. While the importance of TgALD1 in glycolysis is well established and TgDERA is also likely to be involved in parasite metabolism, the detailed function of TgDPA remains elusive. To gain mechanistic insight into the function of different T. gondii aldolases, we first determined the crystal structures of TgALD1 and TgDPA. Structural analysis revealed that both aldolases adopt a TIM barrel fold accessorized with divergent secondary structure elements. Structural comparison of TgALD1 and TgDPA with members of their respective enzyme families revealed that, while the active-site residues are conserved in TgALD1, key catalytic residues are absent in TgDPA. Consistent with this observation, biochemical assays showed that, while TgALD1 was active on F16BP, TgDPA was inactive on dR5P. Intriguingly, both aldolases are competent to bind polymerized actin in vitro. Altogether, structural and biochemical analyses of T. gondii aldolase and aldolase-like proteins reveal diverse functionalization of the classic TIM barrel aldolase fold. Copyright © 2014 Elsevier Ltd. All rights reserved.
Export of a Toxoplasma gondii Rhoptry Neck Protein Complex at the Host Cell Membrane to Form the Moving Junction during Invasion

PubMed Central

Poncet, Joël; Dubremetz, Jean-François; Lebrun, Maryse

2009-01-01

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. PMID:19247437
Phylogenetic Analysis of Nucleus-Encoded Acetyl-CoA Carboxylases Targeted at the Cytosol and Plastid of Algae

PubMed Central

Huerlimann, Roger; Zenger, Kyall R.; Jerry, Dean R.; Heimann, Kirsten

2015-01-01

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
Two new species of Isospora Schneider, 1881 (Apicomplexa: Eimeriidae) from the flap-necked chameleon Chamaeleo dilepis (Sauria: Chamaeleonidae) in the Republic of Namibia.

PubMed

McAllister, Chris T

2012-09-01

Two new species of Isospora Schneider, 1881 from flap-necked chameleons Chamaeleo dilepis Leach are described from the faeces of specimens collected in the Republic of Namibia. Oöcysts of Isospora freedi n. sp. from one of four (25%) C. dilepis collected in the East Caprivi District are spherical to subspherical, with a smooth, colourless, bilayered wall, measure 23.7 × 21.2 μm and have a length/width (L/W) ratio of 1.1. The micropyle and the oöcyst residuum are absent but a polar granule is sometimes present. Sporocysts are ovoidal to ellipsoidal and 13.9 × 10.3 μm in size with prominent Stieda and sub-Stieda bodies; and the sporocyst residuum is composed of a compact mass of large globules. The sporozoites contain anterior and posterior refractile bodies with a nucleus between them. Oöcysts of Isopora mandelai n. sp. from three of seven (43%) C. dilepis collected in the Outjo District are ellipsoidal to cylindroidal, with a smooth, colourless, bilayered wall, measure 36.9 × 31.0 μm and have an L/W ratio of 1.2. The micropyle, oöcyst residuum and polar granule are absent. Sporocysts are ovoidal to ellipsoidal, 15.3 × 11.1 μm in size and contain Stieda and sub-Stieda bodies; and the non-membranous sporocyst residuum is composed of granules of various sizes. The sporozoites contain anterior and posterior refractile bodies with a nucleus between them. These two new taxa represent the third and fourth coccidian species reported from C. dilepis.
New host and distributional records for Cryptosporidium sp. (Apicomplexa: Cryptosporidiidae) from lizards (Sauria: Gekkonidae, Scincidae) from the Cook Islands and Vanuatu, South Pacific

USGS Publications Warehouse

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

USGS Publications Warehouse

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.
Description of a new species of Eimeria Schneider, 1875 (Apicomplexa: Eimeriidae) from the western Derby eland Taurotragus derbianus derbianus Gray (Artiodactyla: Bovidae) in Senegal.

PubMed

Máca, Ondřej

2012-06-01

Examination of faecal samples from semi-captive western Derby elands Taurotragus derbianus derbianus Gray, in the Bandia and Fathala Reserves of Senegal, revealed the presence of oöcysts of the genus Eimeria Schneider, 1875 that we considered to represent a new species, Eimeria derbiani n. sp. The new species possesses nearly ellipsoidal oöcysts (length/width ratio 1.3) with a bi-layered wall and an average size of 27.6 × 21.5 μm. E. derbiani possesses a micropyle covered by a micropylar cap and ovoidal, single-layered sporocysts with an average size of 14.9 × 7.7 μm, each with a Stieda body. Sporozoites of E. derbiani possess a large refractile body and a nucleus. Sporulation lasted for 2 days at 23°C. The new species is differentiated from the two species parasitising Taurotragus oryx Pallas, E. canna Triffitt, 1924 and E. triffittae Yakimoff, 1934.
Molecular investigations of the bat tick Argas vespertilionis (Ixodida: Argasidae) and Babesia vesperuginis (Apicomplexa: Piroplasmida) reflect "bat connection" between Central Europe and Central Asia.

PubMed

Hornok, Sándor; Szőke, Krisztina; Görföl, Tamás; Földvári, Gábor; Tu, Vuong Tan; Takács, Nóra; Kontschán, Jenő; Sándor, Attila D; Estók, Péter; Epis, Sara; Boldogh, Sándor; Kováts, Dávid; Wang, Yuanzhi

2017-05-01

Argas vespertilionis is a geographically widespread haematophagous ectoparasite species of bats in the Old World, with a suspected role in the transmission of Babesia vesperuginis. The aims of the present study were (1) to molecularly screen A. vespertilionis larvae (collected in Europe, Africa and Asia) for the presence of piroplasms, and (2) to analyze mitochondrial markers of A. vespertilionis larvae from Central Asia (Xinjiang Province, Northwestern China) in a phylogeographical context. Out of the 193 DNA extracts from 321 A. vespertilionis larvae, 12 contained piroplasm DNA (10 from Hungary, two from China). Sequencing showed the exclusive presence of B. vesperuginis, with 100% sequence identity between samples from Hungary and China. In addition, A. vespertilionis cytochrome oxidase c subunit 1 (cox1) and 16S rRNA gene sequences had 99.1-99.2 and 99.5-100% similarities, respectively, between Hungary and China. Accordingly, in the phylogenetic analyses A. vespertilionis from China clustered with haplotypes from Europe, and (with high support) outside the group formed by haplotypes from Southeast Asia. This is the first molecular evidence on the occurrence of B. vesperuginis in Asia. Bat ticks from hosts in Vespertilionidae contained only the DNA of B. vesperuginis (in contrast with what was reported on bat ticks from Rhinolophidae and Miniopteridae). Molecular taxonomic analyses of A. vespertilionis and B. vesperuginis suggest a genetic link of bat parasites between Central Europe and Central Asia, which is epidemiologically relevant in the context of any pathogens associated with bats.
Detection and Identification of Sarcocystis cruzi (Protozoa: Apicomplexa) by Molecular and Ultrastructural Studies in Naturally Infected Korean Cattle (Bos taurus coreanae) from Daejeon, Korea.

PubMed

Choi, Tong-Il; Hong, Eui-Ju; Ryu, Si-Yun; Sim, Cheolho; Chae, Joon-Seok; Kim, Hyeon-Cheol; Park, Jinho; Choi, Kyoung-Seong; Yu, Do-Hyeon; Yoo, Jae-Gyu; Park, Bae-Keun

2018-04-01

To survey the prevalence of Sarcocystis infections, 210 heart samples were collected from Korean native cattle ( Bos taurus coreanae ) at an abattoir in Daejeon Metropolitan City, Republic of Korea. Sarcocysts were detected form 31 specimens (14.8%) and identified as Sarcocystis cruzi via transmission electron microscopy. The wall of S. cruzi has flattened protrusions that did not contain fibrils or microfilaments. The protrusions arose irregularly from the base, contained a fine granular substance, lacked internal microfilaments, and measured approximately 0.21-1.25 μm in length and 0.05-0.07 μm in width. Sequence analysis revealed 99.5% homology to S. cruzi . This is the first report on the prevalence of S. cruzi in native cattle from the Republic of Korea.
Reproductive effort and seasonality associated with male-biased parasitism in Gracilinanus agilis (Didelphimorphia: Didelphidae) infected by Eimeria spp. (Apicomplexa: Eimeriidae) in the Brazilian cerrado.

PubMed

Strona, A L S; Levenhagem, M; Leiner, N O

2015-07-01

The aggregation of parasites among hosts is associated with differential host exposure and susceptibility to parasites, which varies according to host gender, body size, reproductive status and environmental factors. We evaluated the role of these factors on infestation by Eimeria spp. (Eimeriidae) in the agile gracile mouse opossum (Gracilinanus agilis), a semelparous didelphid inhabiting neotropical savannahs. Eimeria spp. abundance and prevalence among G. agilis were associated with the breeding status of individuals and to a lesser extent to climatic season, with both sexes presenting higher Eimeria spp. burdens during late breeding/wet season. On the other hand, male-biased parasitism was restricted to dry/mating season. We suggest that male spatial organization and diet may account for increased parasite burdens within this sex, although future studies should evaluate the role of physiological differences associated with androgen hormones. Finally, a rapid increase in Eimeria spp. loads among females during the late breeding/wet season seems associated with seasonal changes in susceptibility, due to breeding costs related to semelparity, and exposure to infective propagules, while male-die off seems to explain maintenance of higher Eimeria spp. burdens within this sex in the same period.
The first record of Gregarina typographi Fuchs (Protista: Apicomplexa: Gregarinidae) from the European spruce bark beetle, Ips typographus (Linnaeus) (Coleoptera: Curculionidae, Scolytinae) in Turkey.

PubMed

Yaman, Mustafa; Bakı, Hilal

2010-01-01

Aim of this study is determining pathogens of Ips typographus from Eastern Black Sea Region in Turkey. Samples collected from the field were taken to laboratuar as soon as possible. Microscopic examination was completed by dissection with Ringer's solution. 780 Ips typographus beetles from Giresun, Rize and Artvin were examined. Gregarines were observed in the populations of I. typographus in the three regions. 27 of 780 beetles were found to be infected by the Gregarina typographi. Total rate of infection was 3.4% in three localities. During the study several life stages of the gregarine pathogen (trophozoite, gamont, Cysts and associative form) were observed. Gametocysts were spherical and from 77 to 85 μm in diameter. Total lengths of solitary gamonts were measured. from 90 to 155 μm. Measurements of gamonts and gametocysts of G. typographi were given and compared with other gregarines isolated from bark beetles. This pathogen is described as Gregarina typographi. The gregarine pathogen of Ips typographus is reported from Turkey for the first time.
Coccidian oöcysts as type-specimens: long-term storage in aqueous potassium dichromate solution preserves DNA.

PubMed

Williams, R B; Thebo, P; Marshall, R N; Marshall, J A

2010-05-01

Preservation of the exogenous oöcyst stage of coccidian parasites (phylum Apicomplexa N.D. Levine, 1970) as type-specimens of newly described species has long been problematical. Conventional fixatives have proved unsatisfactory, and compromises such as embedding oöcysts in resin or photographing them are not entirely appropriate for various reasons. As an alternative, chilled potassium dichromate solution (normally used in the laboratory to prevent putrefaction of temporary preparations of live oöcysts) has been tested as a long-term preservative of sporulated oöcysts of Eimeria brunetti P.P. Levine, 1942, E. maxima Tyzzer, 1929, E. mitis Tyzzer, 1929, E. necatrix Johnson, 1930, E. praecox Johnson, 1930 and E. tenella (Railliet & Lucet, 1891) (suborder Eimeriorina Léger, 1911; family Eimeriidae Minchin, 1903). Oöcysts from faeces of chickens Gallus gallus (Linnaeus) were placed in 2.5% w/v aqueous potassium dichromate solution (PDS) and stored in the dark at 4 +/- 2 degrees C. After 23 years in storage, oöcysts of each species were administered orally to chickens and failed to initiate infections, indicating that the oöcysts were dead. Nevertheless, after about 24 years, DNA was still recoverable from the oöcysts, and the original species identifications made by classic parasitological methods were confirmed by polymerase chain reaction assays. Furthermore, after almost 25 years, microscopical examination revealed that the walls and internal structures remained well preserved in 83-98% of the oöcysts of the six species investigated. Hence, PDS is potentially suitable for the long-term preservation of sporulated coccidian oöcysts as type-specimens for taxonomic purposes. The samples used in this study are now in the care of the Natural History Museum, London, UK. It is recommended that they be monitored in like manner, by suitably qualified scientists, at intervals of about 5 years to assess their state of preservation and the recoverability of DNA
Identification of T. gondii Myosin Light Chain-1 as a Direct Target of TachypleginA-2, a Small-Molecule Inhibitor of Parasite Motility and Invasion

PubMed Central

Leung, Jacqueline M.; Tran, Fanny; Pathak, Ravindra B.; Poupart, Séverine; Heaslip, Aoife T.; Ballif, Bryan A.; Westwood, Nicholas J.; Ward, Gary E.

2014-01-01

Motility of the protozoan parasite Toxoplasma gondii plays an important role in the parasite’s life cycle and virulence within animal and human hosts. Motility is driven by a myosin motor complex that is highly conserved across the Phylum Apicomplexa. Two key components of this complex are the class XIV unconventional myosin, TgMyoA, and its associated light chain, TgMLC1. We previously showed that treatment of parasites with a small-molecule inhibitor of T. gondii invasion and motility, tachypleginA, induces an electrophoretic mobility shift of TgMLC1 that is associated with decreased myosin motor activity. However, the direct target(s) of tachypleginA and the molecular basis of the compound-induced TgMLC1 modification were unknown. We show here by “click” chemistry labelling that TgMLC1 is a direct and covalent target of an alkyne-derivatized analogue of tachypleginA. We also show that this analogue can covalently bind to model thiol substrates. The electrophoretic mobility shift induced by another structural analogue, tachypleginA-2, was associated with the formation of a 225.118 Da adduct on S57 and/or C58, and treatment with deuterated tachypleginA-2 confirmed that the adduct was derived from the compound itself. Recombinant TgMLC1 containing a C58S mutation (but not S57A) was refractory to click labelling and no longer exhibited a mobility shift in response to compound treatment, identifying C58 as the site of compound binding on TgMLC1. Finally, a knock-in parasite line expressing the C58S mutation showed decreased sensitivity to compound treatment in a quantitative 3D motility assay. These data strongly support a model in which tachypleginA and its analogues inhibit the motility of T. gondii by binding directly and covalently to C58 of TgMLC1, thereby causing a decrease in the activity of the parasite’s myosin motor. PMID:24892871
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).

PubMed

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. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

Morphological and morphometrical characterization of gametocytes of Hepatozoon procyonis Richards, 1961 (Protista, Apicomplexa) from a Brazilian wild procionid Nasua nasua and Procyon cancrivorus (Carnivora, Procyonidae).

PubMed

Soares Ferreira Rodrigues, André Flávio; Daemon, Erik; Massard, Carlos Luiz

2007-01-01

The species Hepatozoon procyonis Richards, 1961 was described in Procyon lotor in the USA and then in other reports in the USA, while in Panama H. procyonis has been described in Procyon cancrivorus. The objective of this paper is to report the occurrence of this species in the Brazilian procionids P. cancrivorus and Nasua nausa and to describe the morphology and morphometrics of the gametocytes. The analysis was based on blood smears, stained with Giemsa, which were examined under a photonic microscope. The morphometry was done with an ocular micrometer. It was based on the morphological characteristics and morphometric data on the gametocyte. It can be concluded that the species of the genus Hepatozoon that occurs in Brazilian procionids is the same as that occurring in procionids in Central and North America.
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).

PubMed

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.
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.

PubMed

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.
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

USGS Publications Warehouse

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.
Coccidial dispersion across New World marsupials: Klossiella tejerai Scorza, Torrealba & Dagert, 1957 (Apicomplexa: Adeleorina) from the Brazilian common opossum Didelphis aurita (Wied-Neuwied) (Mammalia: Didelphimorphia).

PubMed

Dos Santos, Caroline Spitz; Berto, Bruno Pereira; do Bomfim Lopes, Bruno; Cordeiro, Matheus Dias; da Fonseca, Adivaldo Henrique; Filho, Walter Leira Teixeira; Lopes, Carlos Wilson Gomes

2014-09-01

Klossiella tejerai Scorza, Torrealba & Dagert, 1957 is a primitive coccidian parasite reported from the New World marsupials Didelphis marsupialis (Linnaeus) and Marmosa demerarae (Thomas). The current work describes K. tejerai from the Brazilian common opossum Didelphis aurita (Wied-Neuwied) in Southeastern Brazil, evidencing the coccidial dispersion across opossums of the same family. The sporocysts recovered from urine samples were ellipsoidal, 20.4 × 12.7 µm, with sporocyst residuum composed of scattered spherules and c.13 sporozoites per sporocyst, with refractile bodies and nucleus. Macrogametes, microgametes, sporonts, sporoblasts/sporocysts were identified within parasitophorous vacuoles of epithelial cells located near the renal corticomedullary junction. Didelphis marsupialis should not have transmitted K. tejerai to D. aurita because they are not sympatric; however M. demerarae is sympatric with D. marsupialis and D. aurita. Therefore, D. aurita becomes the third host species for K. tejerai in South America.
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.

PubMed

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.
Eimeria peltocephali n. sp., (Apicomplexa:Eimeriidae) from the freshwater turtle Peltocephalus dumerilianus (Chelonia:Pelomusidae) and Eimeria molossi n. sp., from the bat, Molossus ater (Mammalia:Chiroptera).

PubMed

Lainson, R; Naiff, R D

1998-01-01

The oocyst is described of Eimeria peltocephali n.sp. from faeces of the freshwater turtle Peltocephalus dumerilianus from Barcelos, State of Amazonas, Brazil. Sporulation is exogenous and fully developed oocysts are elongate, ellipsoidal or cylindrical, frequently curved to a banana-shape, 54.4 x 19.1 (37.5-68.7 x 18.7-20.0 microns), shape-index 2.8 (1.8-3.9). The oocyst wall is a single thin, colourless layer about 1 micron thick, with no micropyle. There is a bulky oocyst residuum, at first spherical to ellipsoidal, 19 x 16 (16.2-26.2 x 16-21.5 microns), but becoming dispersed on maturation. There are no polar bodies. The sporocysts, 19.1 x 6.8 (17.5-21.2 x 6.2-7.5 microns), shape-index 2.8 (2.3-3.2), are usually disposed in pairs at each end of the oocyst, and bear an inconspicuous Stieda body in the form of a flat cap. The sporozoites are elongate and slightly curved around the residuum. No refractile bodies were seen. Eimeria molossi n.sp., is described from the molossid bat Molossus ater. Sporulation is exogenous and the mature oocysts are predominantly broadly ellipsoidal, 23.4 x 17.5 (18-30 x 15-22.5 microns), shape-index 1.3 (1-1.6). The oocyst wall is about 2 microns thick, and of three layers: an inner thin, colourless one and two outer layers which are thicker, yellowish-brown, prominently striated and in close apposition. There is no micropyle or oocyst residuum, but one and occasionally two polar bodies are usually present. Sporocysts are ellipsoidal, 10.2 x 7.5 (10-12.5 x 7.5 microns), shape-index 1.4 (1.3-1.7) with an inconspicuous Stieda body. Endogenous stages are described in the epithelial cells of the small intestine.
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.

PubMed

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. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
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.

PubMed

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.
Monocystis julkae sp.nov., (Protista: Apicomplexa: Monocystidae) a new aseptate gregarine species of the genus Monocystis Stein, 1848 obtain from an Indian Earthworm, Eutyphoeus kherai, Julka, 1978.

PubMed

Bhowmik, Biplab; Bandyopadhyay, P K

2017-03-01

During the course of a biodiversity survey of the endoparasitic aseptate gregarines in the Malda district of West Bengal, India, seminal vesicles of the earthworm, Eutyphoeus kherai , Julka 1978 were found to be infested with a new species, Monocystis julkae sp.nov., of the genus, Monocystis Stein (Arch Anat Phys Med 181-223, 1848). The trophozoite is elongated but slightly constricted posteriorly. A tail like protrusion appears in the posterior end. Anterior end is rather wider than the posterior one. The whole body size of the trophozoite measures 102.2-184.0 (126.7 ± 19.9) µm × 40.9-81.8 (58.2 ± 10.0) µm. Size of the nucleus ranges from 10.2 to 16.3 (11.9 ± 1.9) µm × 8.1-12.2 (8.8 ± 1.2) µm. The gametocysts are ovoidal containing two unequal gametocytes. Diameter of it measures 61.3-98.1 (75.8 ± 8.6) µm. Oocysts are navicular and measures 6.9-10.0 (8.7 ± 0.9) µm × 3.0-4.6 (4.3 ± 0.4) µm.
Morphological and molecular characterization of Isospora manorinae n. sp. in a yellow-throated miner (Manorina flavigula wayensis) (Gould, 1840).

PubMed

Yang, Rongchang; Brice, Belinda; Jian, Fuchun; Ryan, Una

2016-04-01

A new Isospora (Apicomplexa:Eimeriidae) species is described from a single yellow-throated miner bird (Manorina flavigula) (subspecies M. f. wayensis) in Western Australia. Sporulated oocysts (n = 32) of this isolate are spherical to subspherical, 22.8 (20.3-23.8) × 18.3 (17.7-18.7) μm, with a shape index (length/width) of 1.25 (1.2-1.3); and a smooth and bilayered oocyst wall, 1.3 μm thick (outer layer 0.9 μm, inner 0.4 μm). A polar granule is present, but the micropyle and oocyst residuum are absent. The sporocysts are lemon-shaped, 15.5 (14.6-15.8) × 9.5 (9.5-10.2) μm, with a shape index of 1.6. Stieda and substieda bodies are present, the Stieda body being knob-like and the substieda body being subspherical-shaped. A sporocyst residuum is present and composed of numerous granules of different size scattered among the sporozoites, a spheroid or subspheroid refractile body is present in the sporozoite. Morphologically, the oocysts from this isolate are different from those of all known valid Isospora spp. Molecular analysis was conducted at 3 loci; the 18S and 28S ribosomal RNA and the mitochondrial cytochrome oxidase (COI) gene. At the 18S locus, this new isolate exhibited 99.2% similarity to Isospora gryphoni and three other Isospora spp. Further analysis of a subgroup of 300 bp long 18S sequences (8), including Isospora anthochaerae was conducted. This new isolate grouped in a clade with I. anthochaerae and exhibited 99.3% similarity. At the 28S locus, this new isolate grouped with I. anthochaerae with which it shared 99.1% similarity. At the COI locus, this new isolate exhibited 96.8% similarity to Isospora sp. JCI-2015 from a spectacled warbler (Sylvia conspicillata) in Spain. Further analysis from a subgroup of shorter COI sequences (n = 13) was performed and this new isolate exhibited 99.1% similarity to I. anthochaerae. Based on morphological and molecular data, this isolate is a new species of Isospora, which is named Isospora manorinae n. sp
Bovine besnoitiosis in Switzerland: imported cases and local transmission.

PubMed

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
Two new species of coccidia (Apicomplexa: Eimeriidae) from leaf-tailed geckos, Uroplatus spp. (Sauria: Gekkonidae) from Madagascar, including a new host of Eimeria brygooi Upton and Barnard, 1987

PubMed Central

McAllister, Chris T.; Seville, R. Scott; Hartdegen, Ruston

2016-01-01

During May and June 2015, four common leaf-tailed geckos, Uroplatus fimbriatus (Schneider), five satanic leaf-tailed geckos, Uroplatus phantasticus (Boulenger), and four mossy leaf-tailed geckos, Uroplatus sikorae Boettger originally collected from Madagascar and housed at the Dallas Zoo, USA, had their faeces examined for coccidian parasites. Eight (62%) geckos were found to be passing oöcysts, including a new eimerian, a new isosporan and a previously described eimerian. Three of four (75%) U. fimbratus (type host) and one of five (20%) U. phantasticus were infected with Eimeria schneideri n. sp.; oöcysts were subspheroidal to ellipsoidal with a bi-layered wall and measured (length × width, L × W) 15.1 × 13.5 µm, with a length/width (L/W) ratio of 1.1. A micropyle and oöcyst residuum were absent but 1–many polar granules were present. Sporocysts were ovoidal, 6.9 × 5.3 µm, L/W 1.3. Stieda, sub-Stieda and para-Stieda bodies were absent. A globular sporocyst residuum was present as dispersed granules. Four of five (80%) U. phantasticus harbored Isospora boulengeri n. sp.; oöcysts were subpheroidal to ellipsoidal with a bi-layered wall and measured 17.3 × 16.0 µm, L/W 1.1. A micropyle and oöcyst residuum were absent but a polar granule was present. Sporocysts were ellipsoidal, 9.5 × 6.9 µm, L/W 1.4. Stieda and sub-Stieda bodies were present but a para-Stieda body was absent. A globular sporocyst residuum was present with dispersed granules. In addition, one of four (25%) U. sikorae was infected with an eimerian indistinguishable from Eimeria brygooi Upton and Barnard, 1987, previously reported from Madagascar day gecko, Phelsuma grandis Gray and golddust day gecko, Phelsuma laticauda (Boettger) from Madagascar. These are the first coccidians described from Uroplatus spp. PMID:27638735
Phylogenetic analyses reveal that Schellackia parasites (Apicomplexa) detected in American lizards are closely related to the genus Lankesterella: is the range of Schellackia restricted to the Old World?

PubMed

Megía-Palma, Rodrigo; Martínez, Javier; Paranjpe, Dhanashree; D'Amico, Verónica; Aguilar, Rocío; Palacios, María Gabriela; Cooper, Robert; Ferri-Yáñez, Francisco; Sinervo, Barry; Merino, Santiago

2017-10-10

Species of Schellackia Reichenow, 1919 have been described from the blood of reptiles distributed worldwide. Recently, Schellackia spp. detected in European and Asian lizards have been molecularly characterised. However, parasites detected in American lizard hosts remain uncharacterised. Thus, phylogenetic affinities between the Old and New World parasite species are unknown. In the present study, we characterised morphologically and molecularly the hemococcidian parasites (sporozoites) that infect three lizard hosts from North America and two from South America. In total, we generated 12 new 18S rRNA gene sequences of hemococcidian parasites infecting New World lizard hosts. By the microscopic examination of the smears we identified Schellackia golvani Rogier & Landau, 1975 (ex Anolis carolinensis Voigt) and Schellackia occidentalis Bonorris & Ball, 1955 (ex Uta stansburiana Baird & Girard and Sceloporus occidentalis Baird & Girard) in some samples, but the phylogenetic analysis indicated that all 18S rDNA sequences are distant from Schellackia species found in Old World lizards. In fact, the hemococcidian parasites detected in the New World lizards (including S. occidentalis and S. golvani) were closely related to the genus Lankesterella Labbé, 1899. Consequently, we suggest these two species to be included within the genus Lankesterella. Life history traits of hemococcidian parasites such as the type of host blood cells infected, host species or number of refractile bodies are not valid diagnostic characteristics to differentiate the parasites between the genera Schellackia and Lankesterella. Indeed, lankesterellid parasites with a different number of refractile bodies had a close phylogenetic origin. Based on the phylogenetic results we provide a systematic revision of the North American hemococcidians. Our recommendation is to include the species formerly described in the genus Schellackia that infect American lizards into Lankesterella (Lankesterellidae) as Lankesterella golvani (Rogier & Landau, 1975) n. comb and L. occidentalis (Bonorris & Ball, 1955) n. comb.
Helminth (Cestoda, Nematoda) and coccidian (Apicomplexa: Eimeriidae) parasites of the eastern small-footed myotis, Myotis leibii (Chiroptera: Vespertilionidae) from Arkansas, with a description of a new species of Eimeria.

PubMed

McAllister, Chris T; Seville, R Scott; Bursey, Charles R

2017-06-01

During May and July 2016, 32 eastern small-footed myotis (Myotis leibii) were collected from five counties of northwestern Arkansas and their faeces examined for coccidian parasites. Four of 32 (13%) M. leibii harboured an eimerian that we describe here as new. Oocysts of Eimeria sassei sp. n. were ovoidal to ellipsoidal with a bi-layered wall and measured (length × width, L × W) 18.3 × 15.2 µm, with an L/W ratio of 1.2. A micropyle and oocyst residuum were absent but 1-2 polar granules were present. Sporocysts were ovoidal, 9.6 × 6.3 µm, with an L/W ratio of 1.5. A pronounced, button-like Stieda body was present but substieda and parastieda bodies were absent. A sporocyst residuum was present as distinct aligned or dispersed granules. One bat that we found dead was examined for helminth parasites. It harbored the tapeworm, Vampirolepis sp. and a nematode, Seuratum cancellatum. This is the first coccidian as well as the second helminths reported from M. leibii. In addition, this is the seventh species of coccidian parasite documented from Arkansas bats.
Sarcocystis arieticanis (Apicomplexa: Sarcocystidae) infecting the heart muscles of the domestic sheep, Ovis aries (Artiodactyla: Bovidae), from K. S. A. on the basis of light and electron microscopic data.

PubMed

Al Quraishy, Saleh; Morsy, Kareem; Bashtar, Abdel-Rahman; Ghaffar, Fathy Abdel; Mehlhorn, Heinz

2014-10-01

In the present study, the heteroxenous life cycle of Sarcocystis species from three strains of the slaughtered sheep at Al-Azizia and Al-Saada abattoirs in Riyadh city, K.S.A., was studied. Muscle samples of the oesophagus, diaphragm, tongue, skeletal and heart muscles were examined. Varied natural infection rates in the muscles of the examined sheep strains were recorded as 83% in Niemy, 81.5% in Najdy and 90% in Sawakny sheep. Muscles of the diaphragm showed the highest infection level above all organs except Najdy sheep in which oesophagus has the highest rate. Also, the heart was the lowest infected organ (40% Niemy, 44% Najdy and 53% Sawakny). Microscopic sarcocysts of Sarcocystis arieticanis are easily identified in sections through the heart muscles of the domestic sheep Ovis aries (Artiodactyla: Bovidae). Cysts measured 38.5-64.4 μm (averaged 42.66 μm) in width and 62.4-173.6 μm (averaged 82.14 μm) in length. The validity of this species was confirmed by means of ultrastructural characteristics of the primary cyst wall (0.1-0.27 μm thick) which revealed the presence of irregularly shaped crowded and hairy-like projections underlined by a thin layer of ground substance. This layer consisted mainly of fine, dense homogenous granules enclosing the developing metrocytes and merozoites that usually contain nearly all the structures of the apical complex and fill the interior cavity of the cyst. Several septa derived from the ground substance divided the cyst into compartments. The merozoites were banana-shaped and measured 12-16 μm in length with centrally or posteriorly located nuclei. Experimental infection of carnivores by feeding heavily infected sheep muscles revealed that the dog, Canis familiaris, is the only final host of the present Sarcocystis species. Gamogony, sporogonic stages and characteristics of sporulated oocysts were also investigated.
Fitting hidden Markov models of protein domains to a target species: application to Plasmodium falciparum

PubMed Central

2012-01-01

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/ PMID:22548871
Fitting hidden Markov models of protein domains to a target species: application to Plasmodium falciparum.

PubMed

Terrapon, Nicolas; Gascuel, Olivier; Maréchal, Eric; Bréhélin, Laurent

2012-05-01

Hidden Markov Models (HMMs) are a powerful tool for protein domain identification. The Pfam database notably provides a large collection of HMMs which are widely used for the annotation of proteins in new sequenced organisms. In Pfam, each domain family is represented by a curated multiple sequence alignment from which a profile HMM is built. In spite of their high specificity, HMMs may lack sensitivity when searching for domains in divergent organisms. This is particularly the case for species with a biased amino-acid composition, such as P. falciparum, the main causal agent of human malaria. In this context, fitting HMMs to the specificities of the target proteome can help identify additional domains. Using P. falciparum as an example, we compare approaches that have been proposed for this problem, and present two alternative methods. Because previous attempts strongly rely on known domain occurrences in the target species or its close relatives, they mainly improve the detection of domains which belong to already identified families. Our methods learn global correction rules that adjust amino-acid distributions associated with the match states of HMMs. These rules are applied to all match states of the whole HMM library, thus enabling the detection of domains from previously absent families. Additionally, we propose a procedure to estimate the proportion of false positives among the newly discovered domains. Starting with the Pfam standard library, we build several new libraries with the different HMM-fitting approaches. These libraries are first used to detect new domain occurrences with low E-values. Second, by applying the Co-Occurrence Domain Discovery (CODD) procedure we have recently proposed, the libraries are further used to identify likely occurrences among potential domains with higher E-values. We show that the new approaches allow identification of several domain families previously absent in the P. falciparum proteome and the Apicomplexa phylum, and
Morphological and molecular characterization of Isospora neochmiae n. sp. in a captive-bred red-browed finch (Neochmia temporalis) (Latham, 1802).

PubMed

Yang, Rongchang; Brice, Belinda; Ryan, Una

2016-07-01

A new Isospora (Apicomplexa: Eimeriidae) species is described from a single red-browed finch (Neochmia temporalis) (subspecies N. temporalis temporalis), that was part of a captive population in Western Australia. Sporulated oocysts of this isolate are spherical, 18.3 (18.2-18.9) × 18.2 (18.2-18.6) μm, with a shape index (length/width) of 1.0; and a smooth and bilayered oocyst wall, 1.2 μm thick (outer layer 0.9 μm, inner 0.3 μm). A polar granule is present, but the oocyst residuum and a micropyle are absent. The sporocysts are ovoid-shaped, 13.3 (9.5-16.4) × 8.6 (6.8-10.0) μm, with a shape index of 1.5. An indistinct Stieda body is present, but the substieda body is absent. A sporocyst residuum is present and composed of numerous granules of different size scattered among the sporozoites. Morphologically, the oocysts from this isolate are different from those of all known valid Isospora spp. Molecular analysis was conducted at 4 loci; the 18S and 28S ribosomal RNA (rRNA), the mitochondrial cytochrome oxidase (COI) gene and the heat shock protein 70 (hsp70) gene. At the 18S locus, this new isolate exhibited 99.9%, 99.8%, 99.7%, and 99.5% similarity to I. sp. MAH-2013a from a superb starling (Lamprotornis superbus), I. MS-2003 from a Southern cape sparrow (Passer melanurus), I. sp. Tokyo from a domestic pigeon (Columba livia domestica) and I. MS-2003 from a Surinam crested oropendula (Psarocolius decumanus). At the 28S locus, this new isolate exhibited 99.7% similarity to both an Isospora sp (MS-2003) from a Northern house sparrow (Passer domesticus) and an Isospora sp. (MS-2003) from a Southern cape sparrow. At the COI locus, this new isolate exhibited 98.9% similarity to an Isospora sp. ex Apodemus flavicollis. At the hsp70 locus, this new isolate exhibited 99% similarity to isolate MS-2003 (AY283879) from a wattled starling (Creatophora cinerea). Based on morphological and molecular data, this isolate is a new species of Isospora, which is named
A New Host for Caryospora lampropeltis (Apicomplexa: Eimeriidae) from the Eastern Hognose Snake, Heterodon platirhinos (Ophidia: Colubroidea: Dipsadinae), from Arkansas, U.S.A., with a Summary of Hosts of This Coccidian

PubMed Central

Seville, R. Scott; Connior, Matthew B.

2016-01-01

Between May 2012 and July 2013, four eastern hognose snakes (Heterodon platirhinos) were collected from Arkansas (n = 2) and Oklahoma (n = 2), U.S.A., and examined for coccidians. A single H. platirhinos from Arkansas was found to be passing oocysts of Caryospora lampropeltis Anderson, Duszynski, and Marquardt. Oocysts of C. lampropeltis were spheroidal to slightly subspheroidal with a rough, colourless, bi-layered wall, measure 23.5 × 22.8 µm, and have a length/width (L/W) ratio of 1.0; both micropyle and oocyst residuum were absent, but a prominent polar granule was present. Sporocysts are ovoidal, 16.8 × 12.8 µm, L/W 1.3; a prominent Stieda and subStieda body was present; a sporocyst residuum was present and composed of numerous spheroidal granules dispersed into small and large granules. Sporozoites lie lengthwise and parallel in a semi-spiral in sporocyst; a spheroidal anterior refractile and posterior refractile body is present; a single nucleus is located between the 2 refractile bodies. This represents the first report of a caryosporan reported from H. platirhinos as well as the only known coccidian from this host. A summary of hosts of C. lampropeltis is provided. PMID:27917072

Hepatozoon langii n. sp. and Hepatozoon vacuolatus n. sp. (Apicomplexa: Adele-orina: Hepatozoidae) from the crag lizard (Sauria: Cordylidae) Pseudocordylus langi from the North Eastern Drakensberg escarpment, Eastern Free State, South Africa.

PubMed

Van As, Johann; Davies, Angela J; Smit, Nico J

2013-01-22

Two new haemogregarine species, Hepatozoon langii n. sp. and Hepatozoon vacuolatus n. sp., are described from the pe-ripheral blood of the high altitude crag lizard, Pseudocordylus langi, collected between October 2006 and April 2009 from the North Eastern Drakensberg, Eastern Free State. Hepatozoon langii n. sp. has maturing and mature gamonts that appear encapsulated and have narrow, curved tails. Their cytoplasm stains pinkish-purple with Giemsa, while their nuclei are pur-ple stained with stranded chromatin. Mature gamonts measure 19.1 ± 1.0 (15.4-28.1) μm long by 6.2 ± 1.1 (3.5-7.9) μm wide. Hepatozoon vacuolatus n. sp. gamonts are mostly broader at one pole than the other, have bluish-pink cytoplasm characterised by distinctive rounded and oval vacuoles, and demonstrate pink granules with Giemsa staining. Nuclei stain purple and are mainly coarsely granular. Mature gamonts measure 16.5 ± 1.0 (14.7 - 17.6) μm long by 5.9 ± 1.2 (4.0 - 7.7) μm wide. Both species parasitize erythroblasts, as well as erythrocytes and can dehaemoglobinize the cytoplasm of their host cells. Hepatozoon langii n. sp occurred in the absence of H. vacuolatus n. sp., but the latter haemogregarine always formed mixed infections with the former; no stages intermediate between the two haemogregarine types were observed.
[Measuring resistant forms of two pathogenic protozoa (Giardia spp and Cryptosporidium spp) in two aquatic biotopes in Yaoundé (Cameroon)].

PubMed

Gideon, Aghaindum Ajeagah; Njiné, Thomas; Nola, Moïse; Menbohan, Samuel Foto; Ndayo, Marguerite Wouafo

2007-01-01

Organisms of the genera Cryptosporidium and Giardia are enteric parasites that are responsible for cryptosporidiosis and giardiasis respectively. They are characterised by profuse diarrhoea, abdominal pain and cramping. The symptoms can be fatal for immunodepressed subjects and children because these are opportunistic pathogens. These pathogenic infections are rampant in developing countries due to the unhygienic and improper disposal of wastewater and the use of surface water as the major sources of potable water. Little information is available about the resistant forms of these microorganisms in the hydrosystems of Cameroon in particular and other sub-Saharan ecosystems in general. The aim of this research was to isolate, identify, and measure these forms of these emerging protozoa in the waste and surface waters of Yaoundé, Cameroon. Giardia spp cysts were identified by Lugol iodine staining, and the Cryptosporidium spp oocysts by the Ziehl-Neelsen technique. The cysts were oval in structure and varied in length from 7 um to 12.0 um. Axostyles were visible along the median line and nuclei were present. The oocysts were round in structure and varied in diameter from 4 um to 6 um. A double cell wall was seen in the apicomplexa. The highest concentrations of Giardia spp cysts were 560 cysts/L in the surface water and 650 cysts/L in the residual effluent, while the corresponding figures for Cryptosporidium spp were 1,110 oocysts/L in the stream and 1,500 oocysts/L in the effluent. The cyst and oocyst counts were higher in the direct effluent because they are released directly into the wastewater by feces, while they are diluted in the surface water, reducing their abundance. Turbidity has a significant effect (p<0.05) on the population dynamics of these microorganisms, thereby indicating the importance of suspended or colloidal particles in the dissemination of these pathogens in aquatic media. The suspended particles in the wastewater adsorb the oocysts and cysts
Targeted Phenotypic Screening in Plasmodium falciparum and Toxoplasma gondii Reveals Novel Modes of Action of Medicines for Malaria Venture Malaria Box Molecules

PubMed Central

2018-01-01

ABSTRACT The Malaria Box collection includes 400 chemically diverse small molecules with documented potency against malaria parasite growth, but the underlying modes of action are largely unknown. Using complementary phenotypic screens against Plasmodium falciparum and Toxoplasma gondii, we report phenotype-specific hits based on inhibition of overall parasite growth, apicoplast segregation, and egress or host invasion, providing hitherto unavailable insights into the possible mechanisms affected. First, the Malaria Box library was screened against tachyzoite stage T. gondii and the half-maximal effective concentrations (EC50s) of molecules showing ≥80% growth inhibition at 10 µM were determined. Comparison of the EC50s for T. gondii and P. falciparum identified a subset of 24 molecules with nanomolar potency against both parasites. Thirty molecules that failed to induce acute growth inhibition in T. gondii tachyzoites in a 2-day assay caused delayed parasite death upon extended exposure, with at least three molecules interfering with apicoplast segregation during daughter cell formation. Using flow cytometry and microscopy-based examinations, we prioritized 26 molecules with the potential to inhibit host cell egress/invasion during asexual developmental stages of P. falciparum. None of the inhibitors affected digestive vacuole integrity, ruling out a mechanism mediated by broadly specific protease inhibitor activity. Interestingly, five of the plasmodial egress inhibitors inhibited ionophore-induced egress of T. gondii tachyzoites. These findings highlight the advantage of comparative and targeted phenotypic screens in related species as a means to identify lead molecules with a conserved mode of action. Further work on target identification and mechanism analysis will facilitate the development of antiparasitic compounds with cross-species efficacy. IMPORTANCE The phylum Apicomplexa includes many human and animal pathogens, such as Plasmodium falciparum
Antiprotozoan lead discovery by aligning dry and wet screening: prediction, synthesis, and biological assay of novel quinoxalinones.

PubMed

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. Copyright © 2014 Elsevier Ltd. All rights reserved.
[Ultrastructure and cytochemistry of the pellicle and apical complexes of the kinete of Babesia bigemina and Babesia ovis in the hemolymph and oavry of the tick].

PubMed

Weber, G

1980-02-01

alongside this edge. Unlike that of micropores, the plasmalemma of the IPF is not invaginated. The IPF appears as a single, dark ring in tangential sections. At times, rhoptry-like bodies are associated with the openings. The function of the IPF is not known. An intrapellicular opening similar to the IPF, although wider, is present at the apex of the parasite. Its margin coincides with the inners edge of the apical ring. Typical subpellicular microtubuli were not observed in the Babesia kinetes. The apical complex of the B. bigemina kinetes consists of an Apikalschirm (apical umbrella), a crown of microtubuli beneath it, and rhoptries: micronemes are also present in large numbers. The Apikalschirm is located beneath the pellicle of the apical pole of the parasite. It is a wheel-like structure composed of spokes radiating from a wide, hub=like central ring (apical ring). It should be stressed that the apical ring is not identical with the polar ring described as an integral part of the pellicular complex in other Apicomplexa...

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