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effects of methylglyoxal bis(ganylhydrazone) on trypanosomatid flagellates: inhibition of growth and nucleoside incorporation in trypanosoma brucei.methyglyoxal bis (guanylhydrazone) (mgbg) at 0.5 mm had little effect in vitro on blastocrithidia culicis, crithidia oncopelti, and leishmania spp., but completely inhibited growth of trypanosoma brucei. inhibition became irreversible after a 3-h exposure of t. brucei culture procyclics. treated organisms remained motile, but failed to divide. polyamines, spermidine, and spermine, did not reverse the anti-trypanosome action of mgbg (preloading of cells or concurrent administration). two intraper ...1978660567
symbiote-free hemoflagellates, blastocrithidia culicis and crithidia oncopelti: their liver factor requirement and serologic identity.several aposymbiotic strains of blastocrithidia culicis and crithidia oncopelti were cultivated in trager's chemically defined medium as well as in a blood broth, both supplemented with 0.25% (v/v) liver extract concentrate. for all such strains, the liver extract was found to serve as an essential growth factor in the defined medium and as growth promoting additive in the blood broth. the active molecules were found to be water-soluble, heat stable, dialyzable, and probably nonlipid fractions. ...1976933081
the chondriome of selected trypanosomatids. a three-dimensional study based on serial thick sections and high voltage electron microscopy.the unitary nature of the chondriome of two species of trypanosomatids, blastocrithidia culicis and trypanosoma cruzi, has been demonstrated by utilizing serial thick-sectioning techniques combined with high voltage electron microscopy. profiles of mitochondrial elements seen in thin sections and suspected to be parts of a continuum were confirmed by serial thick sectioning (0.25-0.50 mum thick) and stereopair analysis to be parts of the same mitochondrion. three-dimensional models obtained from ...19751095599
characterization of dolichol diphosphate oligosaccharide: protein oligosaccharyltransferase and glycoprotein-processing glucosidases occurring in trypanosomatid protozoa.we have previously reported that the oligosaccharides transferred in vivo from dolichol-p-p derivatives in protein n-glycosylation in trypanosomatids are devoid of glucose residues and contain 2 n-acetylglucosamine and 6, 7, or 9 mannose units depending on the species. in this respect trypanosomatids differ from wild type mammalian, plant, insect, and fungal cells in which glc3man9glcnac2 is transferred. we are now reporting that incubation of glc1-3man9glcnac2-p-p-dolichol and man7-9glcnac2-p-p ...19883053710
characterization of dolichol monophosphate- and dolichol diphosphate-linked saccharides in trypanosomatid flagellates.dolichol-p- and dolichol-p-p-linked saccharides were isolated from several trypanosomatid flagellates incubated with [u-14c]glucose. formation of glc-p-dolichol and man-p-dolichol was observed in herpetomonas muscarum and leishmania adleri, whereas only the latter derivative was synthesized in trypanosoma dionisii and leptomonas samueli. the main and largest dolichol-p-p-linked oligosaccharide formed in trypanosoma conorhini, t. dionisii, l. samueli, herpetomonas samuelpessoai and h. muscarum ap ...19863083254
characterization of protein-linked oligosaccharides in trypanosomatid flagellates.protein-linked, endo-beta-n-acetylglucosaminidase h-sensitive oligosaccharides were isolated from several trypanosomatids incubated with [u-14c]glucose. structural analysis of the compounds revealed that man9glcnac2 was the oligosaccharide transferred from dolichol-p-p derivatives to proteins in trypanosoma dionisii, trypanosoma conorhini, leptomonas samueli and herpetomonas samuelpessoai and man6glcnac2 in blastocrithidia culicis and leishmania adleri. in all cases, transiently glucosylated com ...19863083255
ultrastructural visualization of lipids in trypanosomatids.an imidazole-buffered osmium tetroxide solution was used to visualize lipids at the ultrastructural level in the following members of the family trypanosomatidae: trypanosoma cruzi, t. dionisii, t. vespertilionis. t. rangeli, crithidia deanei, c. fasciculata, c. oncopelti, and blastocrithidia culicis. electron-dense material was seen in various lipid droplets found in all parasites and in the multivesicular structure of members of the sub-genus schizotrypanum. high contrast of some membranes, ma ...19873108493
synthesis of dolichol derivatives in trypanosomatids. characterization of enzymatic patterns.we have previously described that in certain parasitic protozoa, namely the trypanosomatids, the dolichol-p-p-linked oligosaccharides synthesized in vivo and transferred to protein are devoid of glucose residues and contain 6, 7, or 9 mannose units depending on the species. we have now conducted a cell-free characterization of the enzymatic patterns responsible for these phenotypes. microsomes from trypanosoma cruzi, crithidia fasciculata, leishmania enriettii, and blastocrithidia culicis were f ...19873112153
comparative lipid biochemistry. vi. lipids of green and etiolated euglena gracilis and of blastocrithidia culicis. 19676080513
electrophoretic analysis of endonuclease-generated fragments of k-dna, of esterase isoenzymes, and of surface proteins as aids for species identification of insect trypanosomatids.in order to verify the applicability of biochemical methods for species identification of trypanosomatidae, 13 species of monoxenic trypanosomatids plus the heteroxenous trypanosoma cruzi were comparatively analyzed by three different biochemical methods. insect trypanosomatids examined were: crithidia acanthocephali, c. fasciculata (three varieties), c. luciliae luciliae, c. luciliae thermophila, c. deanei, c. oncopelti, herpetomonas muscarum muscarum, h. megaseliae, h. samuelpessoai, h. mariad ...19826284925
cross-reactivity between trypanosoma cruzi and insect trypanosomatids as a basis for the diagnosos of chagas' disease.immunological cross-reactivity between trypanosoma cruzi and insect trypanosomatids was demonstrated by immunofluorescence and confirmed by complement fixation, direct agglutination and cross-absorption experiments. as antigens, the following organisms were surveyed: crithidia deanei, crithidia fasciculata, crithidia luciliae, herpetomonas samuelpessoai, herpetomonas megaseliae, herpetomonas muscarum muscarum, leptomonas seymouri and blastocrithidia culicis. sera from patients with chagas' disea ...19816798889
ultrastructural differences between species of trypanosomatids with and without endosymbionts.species of trypanosomatids without endosymbionts (leptomonas seymouri, l. collosoma, l. samueli, crithidia fasciculata, c. luciliae, c. acanthocephali, herpetomonas megaseliae, h. mariadeanei, h. samuelpessoai, h. muscarum muscarum, trypanosoma cruzi) and species of trypanosomatids with endosymbionts (crithidia deanei, c. oncopelti, blastocrithidia culicis) were comparatively studied by means of electron microscopy. artificially aposymbiotic strains derived from species with symbiont were also i ...19817024533
monophyletic origin of beta-division proteobacterial endosymbionts and their coevolution with insect trypanosomatid protozoa blastocrithidia culicis and crithidia spp.some trypanosomatid protozoa (order kinetoplastida) are well known to harbor bacterial endosymbionts. their phylogenetic positions and evolutionary relationships with the hosts were deduced by comparing the rrna gene sequences. earlier, we observed that these symbionts from three crithidia spp. are identical and are closely related to bordetella bronchiseptica. we have now sequenced the genes of another endosymbiont and the host protozoan blastocrithidia culicis. the 16s rrna genes of the blasto ...19947521530
the presence of galactofuranose and ribose units in asparagine-linked oligosaccharides of the digenetic trypanosomatid endotrypanum schaudinni.it was found that the digenetic trypanosomatid endotrypanum schaudinni transferred man7glcnac2 in protein n-glycosylation. endo-beta-n-acetylglucosaminidase h-sensitive oligosaccharides were identified as man7glcnac2, man6glcnac2, rib1man6glcnac2 and/or gal1man6glcnac2, man5glcnac containing two galactose or ribose units or one of each residues, rib1man5glcnac2 and gal1man5glcnac2. the galactoses were in the furanose configuration. endo-beta-n-acetylglucosaminidase h-resistant glycopeptides that ...19957723790
purification and partial characterization of trypanosoma cruzi triosephosphate isomerase.the enzyme triosephosphate isomerase (tpi, ec 5.3.1.1) was purified from extracts of epimastigote forms of trypanosoma cruzi. the purification steps included: hydrophobic interaction chromatography on phenyl-sepharose, cm-sepharose, and high performance liquid gel filtration chromatography. the cm-sepharose material contained two bands (27 and 25 kda) with similar isoelectric points (pi 9.3-9.5) which could be separated by gel filtration in high performance liquid chromatography. polyclonal anti ...19989698898
the microtubule analog protein, ftsz, in the endosymbiont of trypanosomatid protozoa.blastocrithidia culicis and crithidia deanei are trypanosomatids that harbor an endosymbiotic bacterium in their cytoplasm. in prokaryotes, numerous proteins are essential for cell division, such as ftsz, which is encoded by filament-forming temperature-sensitive (fts) genes. ftsz is the prokaryotic homolog of eukaryotic tubulin and is present in bacteria and archaea, and has also been identified in mitochondria and chloroplasts. ftsz plays a key role in the initiation of cytokinesis. it self-as ...200415352321
use of proteolytic enzymes as an additional tool for trypanosomatid identification.the expression of proteolytic activities in the trypanosomatidae family was explored as a potential marker to discriminate between the morphologically indistinguishable flagellates isolated from insects and plants. we have comparatively analysed the proteolytic profiles of 19 monoxenous trypanosomatids (herpetomonas anglusteri, h. samuelpessoai, h. mariadeanei, h. roitmani, h. muscarum ingenoplastis, h. muscarum muscarum, h. megaseliae, h. dendoderi, herpetomoas sp., crithidia oncopelti, c. dean ...200515700759
proteolytic expression in blastocrithidia culicis: influence of the endosymbiont and similarities with virulence factors of pathogenic trypanosomatids.blastocrithidia culicis is an insect trypanosomatid that presents bacterial endosymbionts. the cell-associated and secreted proteinases of the endosymbiont-bearing and aposymbiotic strains were compared through the incorporation of proteinaceous substrates into sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page). few qualitative changes could be detected in the proteolytic zymograms in the 2 strains studied when gelatin, casein, haemoglobin or bovine serum albumin (bsa) were tes ...200515830815
molecular characterization of type ii topoisomerase in the endosymbiont-bearing trypanosomatid blastocrithidia culicis.dna topoisomerases are involved in dna metabolism. these enzymes are inhibited by antimicrobial and antitumoral agents and might be important targets in the chemotherapy of diseases caused by parasites. we have cloned and characterized the gene encoding topoisomerase ii from the monoxenic trypanosomatid blastocrithidia culicis (bctop2). the bctop2 gene has a 3693 nucleotide-long open reading frame that encodes a 138 kda polypeptide. the b. culicis topoisomerase ii (bctopoii) amino-acid sequence ...200616553848
colonization of aedes aegypti midgut by the endosymbiont-bearing trypanosomatid blastocrithidia culicis.monoxenous trypanosomatids inhabit invertebrate hosts throughout their life cycle. however, there have been cases of hiv-positive patients who have presented opportunistic infections caused by these protozoa, offering new perspectives to the study of interactions between monoxenics and hematophagous insect vectors. some monoxenous trypanosomatids present a symbiotic bacterium in the cytoplasm, which seems to promote biochemical and morphological changes in the host trypanosomatids, such as alter ...200616572337
hiv-1 infection and hiv-1 tat protein permit the survival and replication of a non-pathogenic trypanosomatid in macrophages through tgf-beta1 production.monoxenic trypanosomatids, which usually are non-pathogenic in humans, have been detected in aids patients, but the mechanisms underlying the establishment of these protozoa in hiv-1-infected individuals are poorly understood. here we addressed the role of hiv-1 and the hiv-1 tat protein in the replication of the monoxenic trypanosomatid blastocrithidia culicis in hiv-1-infected primary human macrophages. we found that hiv-1 and b. culicis replication augmented almost three times in co-infected ...200818457978
effect of topoisomerase inhibitors and dna-binding drugs on the cell proliferation and ultrastructure of trypanosoma cruzi.trypanosomatids present unusual organelles, such as the kinetoplast that contains the mitochondrial dna arranged in catenated circles. the nucleus of these protozoa presents distinct domains during interphase as well as a closed mitosis. dna topoisomerases modulate the topological state of dna by regulating supercoiling of the double-stranded dna during replication, transcription, recombination and repair. because topoisomerases play essential roles in cellular processes, they constitute a poten ...201121292448
endosymbiosis in trypanosomatid protozoa: the bacterium division is controlled during the host cell cycle.mutualism is defined as a beneficial relationship for the associated partners and usually assumes that the symbiont number is controlled. some trypanosomatid protozoa co-evolve with a bacterial symbiont that divides in coordination with the host in a way that results in its equal distribution between daughter cells. the mechanism that controls this synchrony is largely unknown, and its comprehension might provide clues to understand how eukaryotic cells evolved when acquiring symbionts that late ...201526082757
predicting the proteins of angomonas deanei, strigomonas culicis and their respective endosymbionts reveals new aspects of the trypanosomatidae family.endosymbiont-bearing trypanosomatids have been considered excellent models for the study of cell evolution because the host protozoan co-evolves with an intracellular bacterium in a mutualistic relationship. such protozoa inhabit a single invertebrate host during their entire life cycle and exhibit special characteristics that group them in a particular phylogenetic cluster of the trypanosomatidae family, thus classified as monoxenics. in an effort to better understand such symbiotic association ...201323560078
structures of trypanosome vacuolar soluble pyrophosphatases: antiparasitic drug targets.trypanosomatid parasites are the causative agents of many neglected tropical diseases, including the leishmaniases, chagas disease, and human african trypanosomiasis. they exploit unusual vacuolar soluble pyrophosphatases (vsps), absent in humans, for cell growth and virulence and, as such, are drug targets. here, we report the crystal structures of vsp1s from trypanosoma cruzi and t. brucei, together with that of the t. cruzi protein bound to a bisphosphonate inhibitor. both vsp1s form a hybrid ...201626907161
new insights about cross-reactive epitopes of six trypanosomatid genera revealed that crithidia and leptomonas have antigenic similarity to l. (l.) chagasi.we investigated whether elisa using crude antigens from insect and plant trypanosomatids, which are non-pathogenic and easily cultivated in large scale, has the same positivity data as leishmania (leishmania) chagasi, the etiological agent of human visceral leishmaniasis (vl) or canine leishmaniasis (canl), or as trypanosoma cruzi, the etiological agent of chagas disease (cd). the antigens from crithidia fasciculata, crithidia luciliae, and leptomonas seymouri showed 100% cross-reactivity with v ...201424275757
actin expression in trypanosomatids (euglenozoa: kinetoplastea).heteroxenic and monoxenic trypanosomatids were screened for the presence of actin using a mouse polyclonal antibody produced against the entire sequence of the trypanosoma cruzi actin gene, encoding a 41.9 kda protein. western blot analysis showed that this antibody reacted with a polypeptide of approximately 42 kda in the whole-cell lysates of parasites targeting mammals (t. cruzi, trypanosoma brucei and leishmania major), insects (angomonas deanei, crithidia fasciculata, herpetomonas samuelpes ...201323903980
the presence of a symbiotic bacterium in strigomonas culicis is related to differential ecto-phosphatase activity and influences the mosquito-protozoa interaction.strigomonas culicis is a monoxenous trypanosomatid that co-evolves with a symbiotic bacterium in a mutualistic relationship that is characterized by intense metabolic exchanges between both partners. s. culicis infects and colonizes the aedes aegypti mosquito midgut, reaches its hemocoel and then invades the salivary glands. an artificial aposymbiotic strain is unable to colonize insects, reinforcing the idea that the bacterium influences the protozoan surface composition and cell interaction. h ...201323562935
interaction of the monoxenic trypanosomatid blastocrithidia culicis with the aedes aegypti salivary gland.blastocrithidia culicis is a monoxenous trypanosomatid that inhabits mosquitoes. although its life cycle in these insects has not been described, we recently demonstrated that b. culicis colonizes the aedes aegypti digestive tract and is also able to reach the mosquito's haemocoel. in this work, we describe the interaction of b. culicis with the a. aegypti salivary gland in vitro and in vivo. ultrastructural analysis reveals different steps of the invasion process, beginning with the insertion o ...201019962365
nutritional significance of symbiotic bacteria in two species of hemoflagellates.symbiote-free strains of blastocrithidia culicis and crithidia oncopelti, obtained by chloramphenicol treatment, were compared nutritionally with normal, symbiote-containing strains. the symbiotic bacteria spare the flagellates requirements for exogenous hemin and for other nutritional factors present in liver extract.19744203488
ultrastructure of symbiotic bacteria in normal and antibiotic-treated blastocrithidia culicis and crithidia oncopelti. 19744217371
reduced growth of blastocrithidia culicis and crithidia oncopelti freed of intracellular symbiotes by chloramphenicol.the intracellular symbiotes of blastocrithidia culicis and crithidia oncopelti can be eliminated from cultures of the flagellates by a single chloramphenicol (cap) treatment. effective dosages were determined to be 0.01-0.08 per cent (w/v) cap after a treatment for 2 weeks or more for b. culicis and 0.08 per cent (w/v) after 1 month for c. oncopelti in most cases. ineffective dosages only lowered the numbers of symbiote-bearing flagellates. growth of both species of flagellates in the presence o ...1975807721
fine structure of blastocrithidia culicis as seen in thin sections and freeze-fracture replicas.the fine structure of epimastigotes of blastocrithidia culicis was studied by transmission electron microscopy of thin sections and freeze-fracture replicas. this parasite presents a well developed endoplasmic reticulum and golgi complex systems. differences in the density and organization of the intramembranous particles were observed between the membranes which enclose the cell body and the flagellum. ridge-like elevations, visualized in freeze-fracture replicas, were observed in sites where t ...19872965931
trypomastigotes in cultures of blastocrithidia culicis (novy, macneal & torrey, 1907) (kinetoplastida: trypanosomatidae). 20037823806
novel (rhamnosyl and ribosyl) and uncommon (xylosyl) monosaccharide residues are present in asparagine-linked oligosaccharides of the trypanosomatid blastocrithidia culicis.blastocrithidia culicis is a trypanosomatid protozoon that transfers man6glcnac2 in protein n-glycosylation. compounds containing mannosyl, xylosyl, and rhamnosyl residues were found among the endo-beta-n-acetylglucosaminidase h-sensitive oligosaccharides of whole cell glycoproteins of this parasite. the compositions of some of them were as follows: man5glcnac2, man6glcnac2, rha1man5glcnac2, rha2man6glcnac2, xyl1rha2man6-glcnac2, xyl1rha3man6glcnac2, and xyl2rha3man6-glcnac2. on the other hand, ...19948051123
cell-associated and extracellular proteinases in blastocrithidia culicis: influence of growth conditions.the proteinase profile of blastocrithidia culicis was analyzed, as well as how different growth conditions influenced its expression by gelatin-sds-page and the use of specific proteinase inhibitors. multiple cell-associated proteinases with molecular masses corresponding to 33, 55, 60 kda (cysteine proteinases) and 77, 80, 90, and 108 kda (metalloproteinases) were detected using these methods. all the metalloproteinases identified were partitioned into the detergent phase after triton x-114 ext ...200111391472
structural characterization of the cell division cycle in strigomonas culicis, an endosymbiont-bearing trypanosomatid.strigomonas culicis (previously referred to as blastocrithidia culicis) is a monoxenic trypanosomatid harboring a symbiotic bacterium, which maintains an obligatory relationship with the host protozoan. investigations of the cell cycle in symbiont harboring trypanosomatids suggest that the bacterium divides in coordination with other host cell structures, particularly the nucleus. in this study we used light and electron microscopy followed by three-dimensional reconstruction to characterize the ...201424397934
the symbiotic bacterium fuels the energy metabolism of the host trypanosomatid strigomonas culicis.the mutualistic relationship between trypanosomatids and their respective endosymbiotic bacteria represents an excellent model for studying metabolic co-evolution since the symbiont completes essential biosynthetic routes of the host cell. in this work, we investigated the influence of the endosymbiont on the energy metabolism of strigomonas culicis by comparing the wild strain with aposymbiotic protists. the bacterium maintains a frequent and close association with glycosomes, which are distrib ...201728371652
endosymbiosis in protozoa of the trypanosomatidae family.a small number of trypanosomatids present bacterium endosymbionts in the cytoplasm, which divide synchronously with the host cell. crithidia oncopleti, crithidia deanei. crithidia desouzai, blastocrithidia culicis and herpetomonas roitmani are the best characterized species. the endosymbiont is surrounded by two membranes separated from each other by an electron-lucent space. the presence of the endosymbiont led to the appearance of morphological changes which include the lack of the paraflagell ...199910220875
phylogenetic validation of the genera angomonas and strigomonas of trypanosomatids harboring bacterial endosymbionts with the description of new species of trypanosomatids and of proteobacterial symbionts.we comparatively examined the nutritional, molecular and optical and electron microscopical characteristics of reference species and new isolates of trypanosomatids harboring bacterial endosymbionts. sequencing of the v7v8 region of the small subunit of the ribosomal rna (ssu rrna) gene distinguished six major genotypes among the 13 isolates examined. the entire sequences of the ssu rrna and glycosomal glyceraldehyde phosphate dehydrogenase (ggapdh) genes were obtained for phylogenetic analyses. ...201121420905
biological effects of lithium chloride on herpetomonas muscarum muscarum and blastocrithidia culicis (kinetoplastida: trypanosomatidae).lithium is widely used in medicine as an antidepressive drug and for myelosuppression attenuation during chemotherapy. in spite of abundant literature, questions on the biological action of lithium ions are far from being answered. we have here examined the effects of lithium (10-200 mm) on culture forms of the trypanosomatid protozoa herpetornonas muscarum muscarum and blastocrithidia culicis. incubation of these parasites with licl inhibited cell growth in a concentration-dependent manner, but ...199910461957
isolation of intracellular symbiotes by immune lysis of flagellate protozoa and characterization of their dna.a new method dependent on immune lysis is described for the isolation of intracellular symbiotes from two species of flagellate protozoa blastocrithidia culicis and crithidia oncopelti. the symbiote-containing flagellates are exposed to complement and antisera prepared in rabbits against symbiote-free organisms. the immune lysis seems to weaken the plasma membranes of the flagellates so that subsequent application of gentle shearing force liberates the intracellular entities in an undamaged cond ...1975805151
five trypanosomatid species of insects distinguished by isoenzymes.blastocrithidia culicis, crithidia deanei, crithidia fasciculata, herpetomonas samuelpessoai, leptomonas seymouri and leishmania tarentolae grown in cultures were compared by electrophoretic mobility for isoenzymes in 6 enzymes. all species were found distinct in these characteristics. endosymbiotic c. deanei, which was identical to the aposymbiotic c. deanei in 5 enzymes, had an extra band in aspartate aminotransferase. no differences in isoenzymes were found between members of one species main ...1979161788
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