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Search Results: 1 - 10 of 12 matches for " kinetoplastida "
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Phylogeny of the kinetoplastida: taxonomic problems and insights into the evolution of parasitism
Maslov, Dmitri A;Podlipaev, Sergei A;Lukes, Julius;
Memórias do Instituto Oswaldo Cruz , 2001, DOI: 10.1590/S0074-02762001000300021
Abstract: to further investigate phylogeny of kinetoplastid protozoa, the sequences of small subunit (18s) ribosomal rna of nine bodonid isolates and ten isolates of insect trypanosomatids have been determined. the root of the kinetoplastid tree was attached to the branch of bodo designis and/or cruzella marina. the suborder trypanosomatina appeared as a monophyletic group, while the suborder bodonina was paraphyletic. among bodonid lineages, parasitic organisms were intermingled with free-living ones, implying multiple transitions to parasitism and supporting the `vertebrate-first hypothesis'. the tree indicated that the genera cryptobia and bodo are artificial taxa. separation of fish cryptobias and trypanoplasma borreli as different genera was not supported. in trypanosomatids, the genera leptomonas and blastocrithidia were polyphyletic, similar to the genera herpetomonas and crithidia and in contrast to the monophyletic genera trypanosoma and phytomonas. this analysis has shown that the morphological classification of kinetoplastids does not in general reflect their genetic affinities and needs a revision.
Phylogeny of the kinetoplastida: taxonomic problems and insights into the evolution of parasitism
Maslov Dmitri A,Podlipaev Sergei A,Lukes Julius
Memórias do Instituto Oswaldo Cruz , 2001,
Abstract: To further investigate phylogeny of kinetoplastid protozoa, the sequences of small subunit (18S) ribosomal RNA of nine bodonid isolates and ten isolates of insect trypanosomatids have been determined. The root of the kinetoplastid tree was attached to the branch of Bodo designis and/or Cruzella marina. The suborder Trypanosomatina appeared as a monophyletic group, while the suborder Bodonina was paraphyletic. Among bodonid lineages, parasitic organisms were intermingled with free-living ones, implying multiple transitions to parasitism and supporting the `vertebrate-first hypothesis'. The tree indicated that the genera Cryptobia and Bodo are artificial taxa. Separation of fish cryptobias and Trypanoplasma borreli as different genera was not supported. In trypanosomatids, the genera Leptomonas and Blastocrithidia were polyphyletic, similar to the genera Herpetomonas and Crithidia and in contrast to the monophyletic genera Trypanosoma and Phytomonas. This analysis has shown that the morphological classification of kinetoplastids does not in general reflect their genetic affinities and needs a revision.
Trypanosomiasis in hybrid catfish (Clarias macrocephalus x Clarias gariepinus) and other freshwater fishes
Supamattaya, K.,Ruangsri, J.,Ruggamol, R.,Songpradit, A.
Songklanakarin Journal of Science and Technology , 2005,
Abstract: The infestation of Trypanosoma sp. (Kinetoplastida) in the hybrid catfish and some fresh water fish was studied showing such parasitic infestation was specific only in catfish. The virulence as determined by LD50 for 5 days was 2.28x1010 cell in a fish sample. The parasitic infestation caused hematological changes by the reduction of red as well as white blood cells. The reductions were highly significant as compared to the healthy sample (p<0.05) as noted by the red and white blood cell count which dropped from 2.14±0.48x106 to 1.62±0.27x106 cells/ml and from 1.45±3.76x105 to 2.42±0.78x104 cells/ml blood in the infested samples, respectively. Similar trend was noted for hemoglobin and hematocrit which dropped significantly (p<0.05). The hemoglobin in healthy fish is 7.075±0.929g/100g, which dropped to 6.268±0.697g/100g in the samples with infestation. The percentage of hematocrit in healthy sample is 25.275±3.318%, which dropped to 21.722±3.068% in the samples with infestation. The reverse trend was recognized for serum protein andleukocrit which increased in the samples with Trypanosoma sp. infestation. The density gradient centrifugation technique was employed in the isolation of parasites in which 50% Percoll solution in 0.85% final preparation of saline solution was capable of removing Trypanosoma sp. from the blood. The study of antibody levels in serum showed that the infested hybrid catfish could develop the antibody which reached a peak 14 days after the infestation. Trypanosoma sp. was unable to cause histological changes in the tissues of gill, liver, kidney, spleen, stomach and intestine. Minor inflammations were observed, even the cases that large number of parasites were found in the tissues, blood streams and sinuses. Marked reductions were recorded for mature red blood cells while there were the formation of immature red blood and phagocytotic cells at higher rates as compared to the healthy individual.
Molecular and biochemical characterisation of Trypanosoma cruzi phosphofructokinase
Rodríguez, Evelyn;Lander, Noelia;Ramirez, Jose Luis;
Memórias do Instituto Oswaldo Cruz , 2009, DOI: 10.1590/S0074-02762009000500014
Abstract: the characterisation of the gene encoding trypanosoma cruzi cl brener phosphofructokinase (pfk) and the biochemical properties of the expressed enzyme are reported here. in contradiction with previous reports, the pfk genes of cl brener and ybm strain t. cruzi were found to be similar to their leishmania mexicana and trypanosoma brucei homologs in terms of both kinetic properties and size, with open reading frames encoding polypeptides with a deduced molecular mass of 53,483. the predicted amino acid sequence contains the c-terminal glycosome-targeting tripeptide skl; this localisation was confirmed by immunofluorescence assays. in sequence comparisons with the genes of other eukaryotes, it was found that, despite being an adenosine triphosphate-dependent enzyme, t. cruzi pfk shows significant sequence similarity with inorganic pyrophosphate-dependent pfks.
Characterization of Endotrypanum Parasites Using Specific Monoclonal Antibodies
Memórias do Instituto Oswaldo Cruz , 1997, DOI: 10.1590/S0074-02761997000100013
Abstract: a large number of endotrypanum stocks (representing an heterogeneous population of strains) have been screened against a panel of monoclonal antibodies (mabs) derived for selected species of endotrypanum or leishmania, to see whether this approach could be used to group/differentiate further among these parasites. using different immunological assay systems, mabs considered specific for the genus endotrypanum (e-24, cxxx-3g5-f12) or strain m6159 of e. schaudinni (e-2, cxiv-3c7-f5) reacted variably according to the test used but in the elisa or immunofluorescence assay both reacted with all the strains tested. analyses using these mabs showed antigenic diversity occurring among the endotrypanum strains, but no qualitative or quantitative reactivity pattern could be consistently related to parasite origin (i.e., host species involved) or geographic area of isolation. western blot analyses of the parasites showed that these mabs recognized multiple components. differences existed either in the epitope density or molecular forms associated with the antigenic determinants and therefore allowed the assignment of the strains to specific antigenic groups. using immunofluorescence or elisa assay, clone e-24 produced reaction with l. equatorensis (which is a parasite of sloth and rodent), but not with other trypanosomatids examined. interestingly, the latter parasite and the endotrypanum strains cross-reacted with a number of mabs that were produced against members of the l. major-l. tropica complex
Leishmania development in sand flies: parasite-vector interactions overview
Dostálová Anna,Volf Petr
Parasites & Vectors , 2012, DOI: 10.1186/1756-3305-5-276
Abstract: Leishmaniases are vector-borne parasitic diseases with 0.9 – 1.4 million new human cases each year worldwide. In the vectorial part of the life-cycle, Leishmania development is confined to the digestive tract. During the first few days after blood feeding, natural barriers to Leishmania development include secreted proteolytic enzymes, the peritrophic matrix surrounding the ingested blood meal and sand fly immune reactions. As the blood digestion proceeds, parasites need to bind to the midgut epithelium to avoid being excreted with the blood remnant. This binding is strictly stage-dependent as it is a property of nectomonad and leptomonad forms only. While the attachment in specific vectors (P. papatasi, P. duboscqi and P. sergenti) involves lipophosphoglycan (LPG), this Leishmania molecule is not required for parasite attachment in other sand fly species experimentally permissive for various Leishmania. During late-stage infections, large numbers of parasites accumulate in the anterior midgut and produce filamentous proteophosphoglycan creating a gel-like plug physically obstructing the gut. The parasites attached to the stomodeal valve cause damage to the chitin lining and epithelial cells of the valve, interfering with its function and facilitating reflux of parasites from the midgut. Transformation to metacyclic stages highly infective for the vertebrate host is the other prerequisite for effective transmission. Here, we review the current state of knowledge of molecular interactions occurring in all these distinct phases of parasite colonization of the sand fly gut, highlighting recent discoveries in the field.
Characterization of Endotrypanum Parasites Using Specific Monoclonal Antibodies
Ramos Franco Antonia Maria,Machado Gerzia MC,Naiff Roberto D,Moreira Celia FS
Memórias do Instituto Oswaldo Cruz , 1997,
Abstract: A large number of Endotrypanum stocks (representing an heterogeneous population of strains) have been screened against a panel of monoclonal antibodies (MAbs) derived for selected species of Endotrypanum or Leishmania, to see whether this approach could be used to group/differentiate further among these parasites. Using different immunological assay systems, MAbs considered specific for the genus Endotrypanum (E-24, CXXX-3G5-F12) or strain M6159 of E. schaudinni (E-2, CXIV-3C7-F5) reacted variably according to the test used but in the ELISA or immunofluorescence assay both reacted with all the strains tested. Analyses using these MAbs showed antigenic diversity occurring among the Endotrypanum strains, but no qualitative or quantitative reactivity pattern could be consistently related to parasite origin (i.e., host species involved) or geographic area of isolation. Western blot analyses of the parasites showed that these MAbs recognized multiple components. Differences existed either in the epitope density or molecular forms associated with the antigenic determinants and therefore allowed the assignment of the strains to specific antigenic groups. Using immunofluorescence or ELISA assay, clone E-24 produced reaction with L. equatorensis (which is a parasite of sloth and rodent), but not with other trypanosomatids examined. Interestingly, the latter parasite and the Endotrypanum strains cross-reacted with a number of MAbs that were produced against members of the L. major-L. tropica complex
Description of Leishmania equatorensis sp. n. (Kinetoplastida: Trypanosomatidae), a new parasite infecting arboreal mammals in Ecuador
Grimaldi Júnior, Gabriel;Kreutzer, Richard D.;Hashiguchi, Yoshihisa;Gomez, Eduardo A.;Mimory, Tatsuyuki;Tesh, Robert B.;
Memórias do Instituto Oswaldo Cruz , 1992, DOI: 10.1590/S0074-02761992000200009
Abstract: characterization is given of a new parasite, leishmania equatoriensis sp.n. wich was isolated from the viscera of a sloth (choloepus hoffmanni) and a squirrel (sciurus granatensis), captured in humid tropical forest onthe pacific coast of ecuador. data based on biological and molecular criteria, as well as numerical zymotaxonomical analysis, indicate that this parasite is a new species of the l. brasiliensis complex. l. equatoriensis is cleary distinguishable form all other known species within this complex, using the following molecular criteria: reactivity patterns with specific monoclonal antibodies, isoenzyme electrophoresis, and restriction-endonuclease fragment patterns of kinetoplast dna (k-dna).
Characterization of Endotrypanum (Kinetoplastida: Trypanosomatidae), a Unique Parasite Infecting the Neotropical Tree Sloths (Edentata)
Franco, Antonia M Ramos;Grimaldi Jr, Gabriel;
Memórias do Instituto Oswaldo Cruz , 1999, DOI: 10.1590/S0074-02761999000200026
Abstract: this article reviews current concepts of the biology of endotrypanum spp. data summarized here on parasite classification and taxonomic divergence found among these haemoflagellates come from our studies of molecular characterization of endotrypanum stocks (representing an heterogenous population of reference strains and isolates from the brazilian amazon region) and from scientific literature. using numerical zymotaxonomy we have demonstrated genetic diversity among these parasites. the molecular trees obtained revealed that there are, at least, three groups (distinct species?) of endotrypanum, which are distributed in central and south america. in concordance with this classification of the parasites there are further newer molecular data obtained using distinct markers. moreover, comparative studies (based on the molecular genetics of the organisms) have shown the phylogenetic relationships between some endotrypanum and related kinetoplastid lineages.
Characterization of Endotrypanum (Kinetoplastida: Trypanosomatidae), a Unique Parasite Infecting the Neotropical Tree Sloths (Edentata)
Franco Antonia M Ramos,Grimaldi Jr Gabriel
Memórias do Instituto Oswaldo Cruz , 1999,
Abstract: This article reviews current concepts of the biology of Endotrypanum spp. Data summarized here on parasite classification and taxonomic divergence found among these haemoflagellates come from our studies of molecular characterization of Endotrypanum stocks (representing an heterogenous population of reference strains and isolates from the Brazilian Amazon region) and from scientific literature. Using numerical zymotaxonomy we have demonstrated genetic diversity among these parasites. The molecular trees obtained revealed that there are, at least, three groups (distinct species?) of Endotrypanum, which are distributed in Central and South America. In concordance with this classification of the parasites there are further newer molecular data obtained using distinct markers. Moreover, comparative studies (based on the molecular genetics of the organisms) have shown the phylogenetic relationships between some Endotrypanum and related kinetoplastid lineages.
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