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Michel Dollet - One of the best experts on this subject based on the ideXlab platform.
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The internal transcribed spacer of ribosomal RNA genes in plant trypanosomes (Phytomonas spp.) resolves 10 groups.
Infection genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases, 2011Co-Authors: Michel Dollet, Nancy R. Sturm, David A. CampbellAbstract:The distinction between plant trypanosomatids and opportunistic monoxenous insect trypanosomatids has not been demarcated clearly due to the mass placement of all trypanosomatids isolated from plants into the arbitrary genus Phytomonas spp. The advent of molecular markers has been useful in distinguishing plant trypanosomatids from the rest of the Trypanosomatidae family. Here we have examined the internal transcribed spacer (ITS) region of the ribosomal RNA (rRNA) locus for classification purposes. This region contains two distinct ITSs flanked by the small subunit and large subunit of ribosomal RNA genes and separated by the 5.8S ribosomal RNA gene. Sequences within the 5.8S ribosomal RNA gene and in the ITS sequences can serve as specific markers for several of the Phytomonas groups. Microsatellite sequences were identified in Phytomonas spp. in both ITS regions. Several classes of microsatellites were seen, with inter-isolate variation that has potential for future use. Maximum Likelihood analysis of the ITS sequences of 20 Phytomonas isolates representing the eight defined groups and a few unclassified isolates revealed a total of 10 distinct subgroups within our collection, of which two are new. The ITS region, which includes the 5.8S sequence, is a robust marker for the subdivisions within the genus Phytomonas spp.
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Large differences in the genome organization of different plant Trypanosomatid parasites (Phytomonas spp.) reveal wide evolutionary divergences between taxa
Infection genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases, 2008Co-Authors: Clotilde Marín, Michel Dollet, Michel Pagès, Patrick BastienAbstract:All currently known plant trypanosomes have been grouped in the genus Phytomonas spp., although they can differ greatly in terms of both their biological properties and effects upon the host. Those parasitizing the phloem sap are specifically associated with lethal syndromes in Latin America, such as, phloem necrosis of coffee, "Hartrot" of coconut and "Marchitez sorpresiva" of oil palm, that inflict considerable economic losses in endemic countries. The genomic organization of one group of Phytomonas (D) considered as representative of the genus has been published previously. The present work presents the genomic structure of two representative isolates from the pathogenic phloem-restricted group (H) of Phytomonas, analyzed by pulsed field gel electrophoresis followed by hybridization with chromosome-specific DNA markers. It came as a surprise to observe an extremely different genomic organization in this group as compared with that of group D. Most notably, the chromosome number is 7 in this group (with a genome size of 10 Mb) versus 21 in the group D (totalling 25 Mb). These data unravel an unsuspected genomic diversity within plant trypanosomatids, that may justify a further debate about their division into different genera. (Resume d'auteur)
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First complete chromosomal organization of a protozoan plant parasite (Phytomonas spp.).
Genomics, 2007Co-Authors: Clotilde Marín, Michel Dollet, Blandine Alberge, Michel Pagès, Patrick BastienAbstract:Abstract Phytomonas spp. are members of the family Trypanosomatidae that parasitize plants and may cause lethal diseases in crops such as Coffee Phloem necrosis, Hartrot in coconut, and Marchitez sorpresiva in oil palm. In this study, the molecular karyotype of 6 isolates from latex plants has been entirely elucidated by pulsed-field gel electrophoresis and DNA hybridization. Twenty-one chromosomal linkage groups constituting heterologous chromosomes and sizing between 0.3 and 3 Mb could be physically defined by the use of 75 DNA markers (sequence-tagged sites and genes). From these data, the genome size can be estimated at 25.5 (± 2) Mb. The physical linkage groups were consistently conserved in all strains examined. Moreover, the finding of several pairs of different-sized homologous chromosomes strongly suggest diploidy for this organism. The definition of the complete molecular karyotype of Phytomonas represents an essential primary step toward sequencing the genome of this parasite of economical importance.
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The first complete molecular karyotype of trypanosomatids (#Phytomonas# sp.) isolated from latex plants (group D)
2006Co-Authors: Clotilde Marín, Michel Dollet, Blandine Alberge, Michel Pagès, Patrick BastienAbstract:The presence of Phytomonas spp. in crops such as coconut and on palm, can have devastating consequences. These infections inflict economic losses, and carry important ecological implications through intensive insecticide treatments. The term "Phytomonas" as a genus has been used since 1909 [1] to classify trypanosomatids isolated from a wide variety of plants. This genus includes three main groups according to the location of the organism in the plant: phloem-restricted, latex and fruit isolates. However, the taxonomy of trypanosomatids isolated from plants is obscure, more especially since several monoxenous genera of "insect trypanosomatids" can multiply in fruit, and are often misidentified as Phytomonas. Even more obscure are the genomics of these parasites, for which neither the ploidy, nor the genome size, nor the chromosome number, are known. (Resume d'auteur)
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Purification and characterization of two iron superoxide dismutases of Phytomonas sp. isolated from Euphorbia characias (plant trypanosomatids).
Parasitology, 2004Co-Authors: C Marín, Michel Dollet, I Rodríguez-gonzález, A B Hitos, M J Rosales, M Sánchez-morenoAbstract:Two superoxide dismutases (SODI and SODII) have been purified by differential centrifugation, fractionation with ammonium sulphate followed by chromatographic separation (ionic exchange and affinity), from a plant trypanosomatid isolated from Euphorbia characias, and then characterized for several biochemical properties. Both enzymes were insensitive to cyanide but sensitive to hydrogen peroxide, properties characteristic of iron-containing superoxide dismutase. SODI had a molecular mass of approximately 66 kDa, whereas the molecular mass of SODII was approximately 22 kDa, both enzymes showing single bands. The isoelectric points of SODI and SODII were 6.8 and 3.6, respectively. The enzymatic stability persisted at least for 6 months when the sample was lyophilized and preserved at -80 degrees C. Digitonin titration and subcellular fractionation showed that both enzymes were in the cytoplasmic fraction, although part of SODII isoenzyme was also associated with glycosomes. We assayed these activities (SOD) in 18 trypanosomatid isolates on isoelectric focusing gels, and have demonstrated that the SOD is a biochemical marker sufficient to identify a trypanosomatid isolated from a plant as belonging to the genus Phytomonas and to distinguish between a true Phytomonas and other trypanosomatids that are capable of causing transient infections in plants.
Manuel Sánchez-moreno - One of the best experts on this subject based on the ideXlab platform.
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Cytotoxicity of Three New Triazolo-pyrimidine Derivatives against the Plant Trypanosomatid: Phytomonas sp. Isolated from
2014Co-Authors: Euphorbia Characias, Clotilde Marín, Rosa Magán, Juan M Salas, Mario Barrera-pérez, Maria J Rosales, Manuel Sánchez-morenoAbstract:There is no effective chemotherapy against diseases caused by Phytomonas sp., a plant trypanosomatid respon-sible for economic losses in major crops. We tested three triazolo-pyrimidine complexes [two with Pt(II), and another with Ru(III)] against promastigotes of Phytomonas sp. isolated from Euphorbia characias. The incorporation of radiolabelled precursors, ultrastructural alterations and changes in the pattern of metabolite excretion were exam-ined. Different degrees of toxicity were found for each complex: the platinun compound showed an inhibition effect on nucleic acid synthesis, provoking alterations on the levels of mitochondria, nucleus and glycosomes. These results, together with others reported previously in our laboratory about the activity of pyrimidine derivatives, reflect the potential of these compounds as agents in the treatment of Phytomonas sp. Key words: Phytomonas sp.- triazolo-pyrimidine complexes- chemotherapeutic agents The name Phytomonas was proposed by Donovan (1909) to designate a trypanosome discovered by Lafont in the same year and initially named Leptomonas davidi. Phytomonas affects more than 100 plant species in about 12 families, causing diseases in plants of substantial eco-nomic interest, such as “sudden wilt ” in the oil palm an
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Cytotoxicity of three new triazolo-pyrimidine derivatives against the plant trypanosomatid: Phytomonas sp. isolated from Euphorbia characias.
Memorias do Instituto Oswaldo Cruz, 2004Co-Authors: Rosa Magán, Clotilde Marín, Juan M Salas, Mario Barrera-pérez, Maria J Rosales, Manuel Sánchez-morenoAbstract:There is no effective chemotherapy against diseases caused by Phytomonas sp., a plant trypanosomatid responsible for economic losses in major crops. We tested three triazolo-pyrimidine complexes [two with Pt(II), and another with Ru(III)] against promastigotes of Phytomonas sp. isolated from Euphorbia characias. The incorporation of radiolabelled precursors, ultrastructural alterations and changes in the pattern of metabolite excretion were examined. Different degrees of toxicity were found for each complex: the platinun compound showed an inhibition effect on nucleic acid synthesis, provoking alterations on the levels of mitochondria, nucleus and glycosomes. These results, together with others reported previously in our laboratory about the activity of pyrimidine derivatives, reflect the potential of these compounds as agents in the treatment of Phytomonas sp.
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Phytomonas spp: superoxide dismutase in plant trypanosomes.
Molecular and biochemical parasitology, 2001Co-Authors: Jose M. Quesada, Emilio Entrala, C. Fernández-ramos, Clotilde Marín, Manuel Sánchez-morenoAbstract:In 1909, Donovan [1] proposed the creation of a new genus, Phytomonas, to differentiate plant from animal trypanosomatids. Phytomonas spp. live in the latex, sap, sieve tubes, and fruit of many plant species [2]. At first, considerable controversy surrounded the pathogenicity of phytomonads in plants, as initially these parasitic protozoans were not thought to be particularly harmful. However, evidence from a number of plants of great economic significance, such as coffee, coconut, and palm, has shown that Phytomonas infections can have devastating economic consequences [3]. The defence mechanisms of trypanosomatids against the toxic products of O2 reduction – e.g. superoxide anion, hydrogen peroxide or hydroxyl radicals – are not completely understood. Trypanosomatids are protected from the damaging effects of reactive oxygen intermediates by scavengers such as trypanothione and specific enzymes such as superoxide dismutase (SOD, EC 1.15.1.1) and trypanothione peroxidase. Catalase, involved in the elimination of hydrogen peroxide, is absent from most trypanosomatids, although it has been detected in Crithidia luciliae [4] and in Phytomonas spp. [5]. Cyanide-insensitive SOD activity has been reported in Trypanosoma cruzi [6], as well as in other trypanosomatids such as Crithidia fasciculata [7] and Trypanosoma brucei [4]. The SOD activities of Leishmania tropica and T. cruzi are also cyanide-insensitive but peroxide-sensitive [7]. SOD of C. fasciculata is located in the cytosol and exists in three forms, which may represent three distinct isozymes. Comparisons of the amino-acid sequence of this SOD with those of SODs from other sources suggest that the crithidial enzyme is closely related to bacterial FeSOD of the alga Euglena gracilis. SOD activity has also been detected in L. dono ani and Phytomonas spp., although its nature has not been determined [8,9]. Most of the information on the biochemistry of plant flagellates has come from experiments in which the flagellates were used as instruments in biochemical research rather than from studies investigating the biochemistry of the plant flagellates themselves. Probably for this reason, these studies are scattered through a variety of subjects, and, despite the amount of information gathered in recent years, our knowledge of the biochemistry of Phytomonas remains fragmentary [3]. In this sense, the detoxifying mechanisms of oxygen radicals in plant trypanosomatids are unknown. From previous studies [10], we know that plant flagellates have SOD activity, but we have yet to identify the role of this enzyme in the destruction of the superoxide radicals, and there is no information available on the enzyme itself. In the present work, we confirm and quantify the SOD activity in three trypanosomes isolated from different plants: from phloem of the Coco nucifera (Hartrot disease) [11], from latex vessels of Euphorbia characias [12], from the fruits of Lycopersicon esculenAbbre iations: Cu/ZnSOD, copper/zinc-containing superoxide dismutase; FeSOD, iron-containing superoxide dismutase; ME, malic enzyme; MnSOD, manganese-containing superoxide dismutase; NBT, nitro-blue tetrazolium salt; PK, pyruvate kinase; PFK, 6-phospho fructose kinase; SOD, superoxide dismutase. * Corresponding author. Tel.: +34-958-242369; fax: +34-958243174. E-mail address: msanchem@goliat.ugr.es (M. Sanchez-Moreno).
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Genus-specific biochemical markers for Phytomonas spp.
Molecular and biochemical parasitology, 1997Co-Authors: Antonio D. Uttaro, Manuel Sánchez-moreno, Fred R. OpperdoesAbstract:Phytomonas spp. are digenetic (two host) flagellated protozoa isolated from plants, with a wide geographical distribution [1,2]. They have been found in 17 different families of plant and are believed to be transmitted by phytophagous hemipteran insects of the families Coreidae, Lygaeidae, Pyrrhocoridae and Pentatomidae [1–5]. Phytomonas spp. have been isolated from latex tubes of laticiferous plants, from the phloem of trees, from mature fruits of many plant families and from seeds such as maize [1–3,6,7]. The intraphloemic isolates, all from South America, are specifically associated with pathological syndromes in plants, while a latex-associated P. francai causes ‘chochamento das raizes’ (empty roots) in manioc [1,2,8]. Classically, Phytomonas spp. have been described as plant trypanosomatids with a typical promastigote appearance [9], but this definition is at least ambiguous, because promastigote stages also occur in Leptomonas and Herpetomonas, flagellates that can be found together with Crithidia and Blastocrithidia, in Phytomonas vectors [1,4], and which have sometimes been detected in plant tissues, probably as transient infections [10]. Therefore, there exist no well defined criteria for attributing different plant-isolated trypanosomes to the genus Phytomonas. A simple and unambiguous marker is thus urgently needed. Agglutination [6,11], isoenzyme profiles [12–14] and immunological methods [15,16], genomic or kinetoplastic DNA fingerprinting [14,17,18], seAbbre6iations: aHADH, a-hydroxyacid dehydrogenase; iPDH, iso-propanol dehydrogenase; MDH, malate dehydrogenase. * Corresponding author. Tel.: +32 2 7647439; fax: +32 2 7626853; e-mail: opperdoes@trop.ucl.ac.be
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Induction of stress proteins in the plant trypanosome Phytomonas characias
Parasitology research, 1997Co-Authors: Manuel Sánchez-moreno, Carmen Fernandez-becerra, Nieves Rodriguez-cabezas, Concepción Mesa-valle, Antonio OsunaAbstract:The present study of the synthesis of new proteins in plant trypanosomatids in the genus Phytomonas as a response to different types of stress demonstrates the production of a number of proteins that can be grouped into four families similar to those that appear in other organisms (heat-shock proteins). In the study of stress, Phytomonas cultures were subjected to changes in temperature from 22° to 37 °C, deprived of glucose, grown in the presence of sodium arsenite, and treated with calcium ionophore. In addition, the culture medium was changed from Grace's medium (330 mosmol/l) to a plant-culture medium with an osmolarity of 286 mosmol/l, implying the exertion of stress during the parasite's normal biological cycle of passage from the insect vector to the plant host. The treatment with actinomycin D demonstrated that some of the mRNAs that codify these proteins are found in normal presynthesized conditions. To measure the effect of temperature on the macromolecule biosynthesis we compared the incorporation of labeled analogues ([3H]-thymidine, [3H]-uridine, and [3H]-leucine) by flagellates cultured at 22 °C with that by parasites cultivated at 37 °C.
David A. Campbell - One of the best experts on this subject based on the ideXlab platform.
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The internal transcribed spacer of ribosomal RNA genes in plant trypanosomes (Phytomonas spp.) resolves 10 groups.
Infection genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases, 2011Co-Authors: Michel Dollet, Nancy R. Sturm, David A. CampbellAbstract:The distinction between plant trypanosomatids and opportunistic monoxenous insect trypanosomatids has not been demarcated clearly due to the mass placement of all trypanosomatids isolated from plants into the arbitrary genus Phytomonas spp. The advent of molecular markers has been useful in distinguishing plant trypanosomatids from the rest of the Trypanosomatidae family. Here we have examined the internal transcribed spacer (ITS) region of the ribosomal RNA (rRNA) locus for classification purposes. This region contains two distinct ITSs flanked by the small subunit and large subunit of ribosomal RNA genes and separated by the 5.8S ribosomal RNA gene. Sequences within the 5.8S ribosomal RNA gene and in the ITS sequences can serve as specific markers for several of the Phytomonas groups. Microsatellite sequences were identified in Phytomonas spp. in both ITS regions. Several classes of microsatellites were seen, with inter-isolate variation that has potential for future use. Maximum Likelihood analysis of the ITS sequences of 20 Phytomonas isolates representing the eight defined groups and a few unclassified isolates revealed a total of 10 distinct subgroups within our collection, of which two are new. The ITS region, which includes the 5.8S sequence, is a robust marker for the subdivisions within the genus Phytomonas spp.
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Internal transcribed spacer of ribosomal RNA genes and microsatellites for characterization of phloem restricted Phytomonas associated with coconut and oil palm wilts
2003Co-Authors: Michel Dollet, Nancy R. Sturm, David A. CampbellAbstract:Phloem-restricted trypanosomatids - Phytomonas - are associated with wilts of oil palm, coconut, coffee, red ginger in Latin America and the Caribbean. The coconut wilt -Hartrot- and Lethal Yellowing phytoplasma disease- have the same symptomatology and can be confused. As similar non-pathogenic trypanosomatids can also be found in plants and insects it is important to have specific tools to diagnose the strains associated with wilts. Here we examine the internal transcribed spacer (ITS) region of the rRNA locus. It contains two distinct ITSs separated by the 5.8S rRNA gene. The ITS - 5.8 S region is a robust marker for characterization of the different types of trypanosomatids and distinguishes the phloem-restricted ones. Microsatellite sequences were identified for the first time in Phytomonas in ITS regions. Several classes were seen, with interisolate variation that has potential for future use in population genetics studies. (Texte integral)
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Kinetoplast DNA minicircles of phloem-restricted Phytomonas associated with wilt diseases of coconut and oil palms have a two-domain structure.
FEMS microbiology letters, 2001Co-Authors: Michel Dollet, J. C. Ahomadegbe, Nancy R. Sturm, David A. CampbellAbstract:We report the cloning and sequencing of the first minicircle from a phloem-restricted, pathogenic Phytomonas sp. (Hart 1) isolated from a coconut palm with hartrot disease. The minicircle possessed a two-domain structure of two conserved regions, each containing three conserved sequence blocks (CSB). Based on the sequence around CSB 3 from Hart 1, PCR primers were designed to allow specific amplification of Phytomonas minicircles. This primer pair demonstrated specificity for at least six groups of plant trypanosomatids and did not amplify from insect trypanosomatids. The PCR results were consistent with a two-domain structure for other plant trypanosomatids.
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The spliced leader RNA gene array in phloem-restricted plant trypanosomatids (Phytomonas) partitions into two major groupings: epidemiological implications.
Parasitology, 2001Co-Authors: Michel Dollet, Nancy R. Sturm, David A. CampbellAbstract:The arbitrary genus Phytomonas includes a biologically diverse group of kinetoplastids that live in a wide variety of plant environments. To understand better the subdivisions within the phytomonads and the variability within groups, the exon, intron and non-transcribed spacer sequences of the spliced leader RNA gene were compared among isolates of the phloemrestricted members. A total of 29 isolates associated with disease in coconut, oil palm and red ginger (Alpinia Purpurata, Zingibreaceae) were examined, all originating from plantations in South America and the Caribbean over a 12-year period. Analysis of non-transcribed spacer sequences revealed 2 main groups, I and II; group II could be further subdivided into 2 subgroups, Ila and Ilb. Three classes of spliced leader (SL) RNA gene were seen, with SLI corresponding to group I, SLIla to group Ila, and SLIlb to group Ilb. Two isolates showed some characteristics of both major groups. Groupspecific oligonucleotide probes for hybridization studies were tested, and a multiplex amplification scheme was devised to allow direct differentiation between the 2 major groups of phloem- restricted Phytomonas. These results provide tools for diagnostic and molecular epidemiology of plant trypanosomes that are pathogenic for commercially important flowers and palms. (Resume d'auteur)
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Research letterThe mini-exon genes of three Phytomonas isolates that differ in plant tissue tropism
Fems Microbiology Letters, 1995Co-Authors: Nancy R. Sturm, Octavio Fernandes, David A. CampbellAbstract:The tandem mini-exon gene repeat is an ideal diagnostic target for trypanosomatids because it includes sequences that are conserved absolutely coupled with regions of extreme variability. We have exploited these features and the polymerase chain reaction to differentiate Phytomonas strains isolated from phloem, fruit or latex of various host plants. While the transcribed regions are nearly identical, the intergenic sequences are variable in size and content (130–332 base pairs). The mini-exon genes of these phytomonads can therefore be distinguished from each other and from the corresponding genes in insect trypanosomes, with which they are oft confused.
Erney P Camargo - One of the best experts on this subject based on the ideXlab platform.
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Phytomonas (Euglenozoa: Trypanosomatidae): Phylogenetic analyses support infrageneric lineages and a new species transmitted to Solanaceae fruits by a pentatomid hemipteran
European journal of protistology, 2016Co-Authors: Andernice Zanetti, Márcia Attias, Wanderley De Souza, Myrna G Serrano, Marta Campaner, Marta Maria Geraldes Teixeira, Robson C. Ferreira, Carmen S. A. Takata, Erney P CamargoAbstract:Abstract The genus Phytomonas includes trypanosomatids transmitted to the fruits, latex, and phloem of vascular plants by hemipterans. We inferred the phylogenetic relationships of plant and insect isolates assigned to the previously defined genetic groups A–F and H of Phytomonas, particularly those from groups A, C and E comprising flagellates of Solanaceae fruits. Phylogenetic analyses using glycosomal Glyceraldehyde Phosphate Dehydrogenase (gGAPDH) and Small Subunit rRNA (SSU rRNA) genes strongly supported the monophyly of the genus Phytomonas and its division into seven main infrageneric phylogenetic lineages (Phy clades). Isolates from fruit or latex do not constitute monophyletic assemblages but disperse through more than one lineages. In this study, fruit flagellates were distributed in three clades: PhyA, formed by isolates from Solanaceae and phytophagous hemipterans; PhyC comprising flagellates from four plant families; and PhyE, which contains 15 fruit isolates from seven species of Solanaceae. The flagellates of PhyE are described as Phytomonas dolleti n. sp. according to their positioning in phylogenetic trees, complemented by data about their life cycle, and developmental and morphological characteristics in cultures, fruits of Solanum spp., and salivary glands of the vector, the phytophagous hemipteran Arvelius albopunctatus (Pentatomidae).
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A PCR-Based Survey on Phytomonas (Euglenozoa: Trypanosomatidae) in Phytophagous Hemipterans of the Amazon Region
The Journal of eukaryotic microbiology, 2002Co-Authors: Mara Maria Izar De Maio Godoi, Myrna G Serrano, Marta Maria Geraldes Teixeira, Erney P CamargoAbstract:Abstract We have surveyed 244 hemipterans from Western Brazilian Amazonia for the presence of trypanosomatids and identification of members of the genus Phytomonas. Examination by phase microscopy of squashes of insect salivary glands (SG) and digestive tubes (DT) revealed that 44% (108/244) of insects from seven families harbored trypanosomatids. Infections were 5 times more frequent in Coreidae than in all other families together. Smears of SG and DT of the dissected insects were fixed on glass slides with methanol and stained with Giemsa for morphological analysis. DNA was recovered from these preparations and submitted to a PCR assay that permitted amplification of all trypanosomatid genera using primers of conserved sequences flanking a segment of the spliced leader (SL) gene. Upon PCR amplification of the recovered DNA, amplicons were hybridized with an oligonucletide probe (SL3′) complementary to a SL intron sequence specific for flagellates of the genus Phytomonas. Among the trypanosomatid-positiv...
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Phytomonas analysis of polymorphism and genetic relatedness between isolates from plants and phytophagous insects from different geographic regions by rapd fingerprints and synapomorphic markers
Journal of Eukaryotic Microbiology, 1999Co-Authors: Myrna G Serrano, Erney P Camargo, Marta Maria Geraldes TeixeiraAbstract:The random amplification of polymorphic DNA was used for easy, quick and sensitive assessment of genetic polymorphism within Phytomonas to discriminate isolates and determine genetic relationships within the genus. We examined 48 Phytomonas spp., 31 isolates from plants and 17 from insects, from different geographic regions. Topology of the dendrogram based on randomly amplified polymorphic DNA fingerprints segregated the Phytomonas spp. into 5 main clusters, despite the high genetic variability within this genus. Similar clustering could also be obtained by both visual and cross-hybridization analysis of randomly amplified synapomorphic DNA fragments. There was some concordance between the genetic relationship of isolates and their plant tissue tropism. Moreover, Phytomonas spp. from plants and insects were grouped according to geographic origin, thus revealing a complex structure of this taxon comprising several clusters of very closely related organisms.
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trypanosomatidae Phytomonas detection in plants and phytophagous insects by pcr amplification of a genus specific sequence of the spliced leader gene
Experimental Parasitology, 1999Co-Authors: Myrna G Serrano, Luiz R Nunes, Marta Campaner, Gregory A Buck, Erney P Camargo, Marta Maria Geraldes TeixeiraAbstract:Abstract Serrano, M. G., Nunes, L. R., Campaner, M., Buck, G. A., Camargo, E. P., and Teixeira, M. M. G. 1999. Trypanosomatidae: Phytomonas detection in plants and phytophagous insects by PCR amplification of a genus-specific sequence of the spliced leader gene. Experimental Parasitology 91 , 268–279. In this paper we describe a method for the detection of Phytomonas spp. from plants and phytophagous insects using the PCR technique by targeting a genus-specific sequence of the spliced leader (SL) gene. PCR amplification of DNA from 48 plant and insect isolates previously classified as Phytomonas by morphological, biochemical, and molecular criteria resulted in all cases in a 100-bp fragment that hybridized with the Phytomonas -specific spliced leader-derived probe SL3′. Moreover, this Phytomonas -specific PCR could also detect Phytomonas spp. in crude preparations of naturally infected plants and insects. This method shows no reaction with any other trypanosomatid genera or with plant and insect host DNA, revealing it to be able to detect Phytomonas spp. from fruit, latex, or phloem of various host plants as well as from salivary glands and digestive tubes of several species of insect hosts. Results demonstrated that SLPCR is a simple, fast, specific, and sensitive method that can be applied to the diagnosis of Phytomonas among cultured trypanosomatids and directly in plants and putative vector insects. Therefore, the method was shown to be a very specific and sensitive tool for diagnosis of Phytomonas without the need for isolation, culture, and DNA extraction of flagellates, a feature that is very convenient for practical and epidemiological purposes.
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Phytomonas and other trypanosomatid parasites of plants and fruit.
Advances in parasitology, 1999Co-Authors: Erney P CamargoAbstract:Abstract Trypanosomatid parasites are fairly common in the latex, phloem, fruit sap, seed albumen, and even in the nectar, of many plant families. They are transmitted to the plants in the saliva of phytophagous hemipterous bugs (Insecta). Morphologically, plant trypanosomatids have no special characteristic, except perhaps a very twisted cell body. Most occur in plants as promastigotes and a few as choanomastigotes. It is still controversial whether or not they are pathogenic in lactiferous plants or fruit, but it is certain that the phloem parasites are pathogenic in coconut palms and coffee bushes. In these plants, they cause lethal diseases responsible for the destruction of many plantations in Central and South America, but fortunately nowhere else in the world. Probably more than one genus of Trypanosomatidae is represented among the plant parasites. The most important is certainly Phytomonas, but Leptomonas, Crithidia and Herpetomonas may also be present. The distinction between them is difficult and only recently have molecular markers become available to help in their identification. At present, Phytomonas can be identified by DNA hybridization with a specific probe (SL3') complementary to a sequence of the mini-exam or spliced leader gene. The development of a polymerase chain reaction coupled to SL3' hybridization has facilitated the detection of Phytomonas in plants. The phylogeny of Phytomonas is still being worked out. For the moment it can only be said that the genus is very close to Herpetomonas.
Steven L. Kelly - One of the best experts on this subject based on the ideXlab platform.
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Genome Sequence of Phytomonas françai, a Cassava (Manihot esculenta) Latex Parasite
Genome announcements, 2017Co-Authors: Claire Butler, Eleanor Jaskowska, Steven L. KellyAbstract:ABSTRACT Here, we report the genome sequence of the cassava (Manihot esculenta) latex parasite Phytomonas francai. P. francai infection is linked with the yield-loss disease “chochamento de raizes” (empty roots) in the Unha variety of cassava, a disease characterized by poor root development and chlorosis of the leaves.
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Description of Phytomonas oxycareni n. sp. from the Salivary Glands of Oxycarenus lavaterae.
Protist, 2016Co-Authors: Emily A. Seward, Julius Lukeš, Jan Votýpka, Petr Kment, Steven L. KellyAbstract:Phytomonas spp. (phytomonads) are a diverse and globally distributed group of unicellular eukaryotes that parasitize a wide range of plants and are transmitted by insect hosts. Here we report the discovery and characterisation of a new species of Phytomonas, named Phytomonas oxycareni n. sp., which was obtained from the salivary glands of the invasive species of true bug Oxycarenus lavaterae (Heteroptera). The new Phytomonas species exhibits a long slender promastigote morphology and can be found both within the lumen of the insect host’s salivary glands as well as within the cells of the salivary gland itself. Sampling multiple individuals from the same population post-winter hibernation on two consecutive years revealed that infection was persistent over time. Finally, phylogenetic analyses of small subunit ribosomal RNA genes revealed that this species is sister to other species within the genus Phytomonas, providing new insight into the evolutionary history of the clade.
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Correction: Phytomonas: trypanosomatids adapted to plant environments.
PLoS pathogens, 2015Co-Authors: Eleanor Jaskowska, Claire Butler, Gail M. Preston, Steven L. KellyAbstract:Fig 1 does not include axis labels and has an outdated plant family name (Palmae). The authors have provided a corrected version here. Fig 1 Summary of all known Phytomonas isolates.
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Phytomonas : Trypanosomatids Adapted to Plant Environments
PLoS pathogens, 2015Co-Authors: Eleanor Jaskowska, Claire Butler, Gail M. Preston, Steven L. KellyAbstract:Over 100 years after trypanosomatids were first discovered in plant tissues, Phytomonas parasites have now been isolated across the globe from members of 24 different plant families. Most identified species have not been associated with any plant pathology and to date only two species are definitively known to cause plant disease. These diseases (wilt of palm and coffee phloem necrosis) are problematic in areas of South America where they threaten the economies of developing countries. In contrast to their mammalian infective relatives, our knowledge of the biology of Phytomonas parasites and how they interact with their plant hosts is limited. This review draws together a century of research into plant trypanosomatids, from the first isolations and experimental infections to the recent publication of the first Phytomonas genomes. The availability of genomic data for these plant parasites opens a new avenue for comparative investigations into trypanosomatid biology and provides fresh insight into how this important group of parasites have adapted to survive in a spectrum of hosts from crocodiles to coconuts.
