The Experts below are selected from a list of 8259 Experts worldwide ranked by ideXlab platform
Robin B Gasser - One of the best experts on this subject based on the ideXlab platform.
-
the developmental phosphoproteome of Haemonchus contortus
Journal of Proteomics, 2020Co-Authors: Tao Wang, Andreas Hofmann, Chingseng Ang, Pasi K Korhonen, Nicholas A Williamson, Neil D Young, Andreas J Stroehlein, Bill C H Chang, Robin B GasserAbstract:Protein phosphorylation plays essential roles in many cellular processes. Despite recent progress in the genomics, transcriptomics and proteomics of socioeconomically important parasitic nematodes, there is scant phosphoproteomic data to underpin molecular biological discovery. Here, using the phosphopeptide enrichment-based LC-MS/MS and data-independent acquisition (DIA) quantitation, we characterised the first developmental phosphoproteome of the parasitic nematode Haemonchus contortus - one of the most pathogenic parasites of ruminant livestock. Totally, 1804 phosphorylated proteins with 4406 phosphorylation sites ('phosphosites') from different developmental stages/sexes were identified. Bioinformatic analyses of quantified 'phosphosites' exhibited distinctive stage- and sex-specific patterns during development, and identified a subset of phosphoproteins proposed to play crucial roles in processes such as spindle positioning, signal transduction and kinase activity. A sequence-based comparison of the phosphoproteome of H. contortus with those of two free-living nematode species (Caenorhabditis elegans and Pristionchus pacificus) suggested a limited number of common protein phosphorylation events among these species. Our findings infer active roles for protein phosphorylation in the adaptation of a parasitic nematode to a constantly changing external environment. The phosphoproteomic data set for H. contortus provides a basis to better understand phosphorylation and associated biological processes (e.g., regulation of signal transduction), and might enable the discovery of novel anthelmintic targets. SIGNIFICANCE: Here, we report the first phosphoproteome for a socioeconomically parasitic nematode (Haemonchus contortus). This phosphoproteome exhibits distinctive patterns during development, suggesting active roles of post-translational modification in the parasite's adaptation to changing environments within and outside of the host animal. This work sheds a light on the developmental phosphorylation in a parasitic nematode, and could enable the discovery of novel interventions against major pathogens.
-
somatic proteome of Haemonchus contortus
International Journal for Parasitology, 2019Co-Authors: Tao Wang, Chingseng Ang, Pasi K Korhonen, Shuai Nie, Anson V Koehler, Richard J Simpson, David W Greening, Gavin E Reid, Nicholas A Williamson, Robin B GasserAbstract:Currently, there is a dearth of proteomic data to underpin fundamental investigations of parasites and parasitism at the molecular level. Here, using a high throughput LC-MS/MS-based approach, we undertook the first reported comprehensive, large-scale proteomic investigation of the barber's pole worm (Haemonchus contortus) - one of the most important parasitic nematodes of livestock animals worldwide. In total, 2487 unique H. contortus proteins representing different developmental stages/sexes (i.e. eggs, L3s and L4s, female (Af) and male (Am) adults) were identified and quantified with high confidence. Bioinformatic analyses of this proteome revealed substantial alterations in protein profiles during the life cycle, particularly in the transition from the free-living to the parasitic phase, and key groups of proteins involved specifically in feeding, digestion, metabolism, development, parasite-host interactions (including immunomodulation), structural remodelling of the body wall and adaptive processes during parasitism. This proteomic data set will facilitate future molecular, biochemical and physiological investigations of H. contortus and related nematodes, and the discovery of novel intervention targets against haemonchosis.
-
the developmental lipidome of Haemonchus contortus
International Journal for Parasitology, 2018Co-Authors: Tao Wang, Chingseng Ang, Pasi K Korhonen, Shuai Nie, Anson V Koehler, Gavin E Reid, Nicholas A Williamson, Robin B GasserAbstract:Lipids play crucial roles in the biology of organisms, particularly relating to cellular membranes, energy storage, and intra- or inter-cellular signalling. Despite the recent expansion of the lipidomics field, very little is known about the biology of lipids in metzoan pathogens, and, to date, there has been no global lipidomic study of a parasitic nematode. Using Haemonchus contortus (barber's pole worm) as a model, we describe the first known global lipidome for a parasitic nematode via high throughput LC-MS/MS-based lipidomics. We identified a total of 554 lipid species across four lipid categories, and 18 lipid classes exhibited alterations among six developmental stages (eggs; L3 and exsheathed L3 (xL3) and L4 larval stages; female and male adults) of H. contortus. The lipid composition and abundance of H. contortus changed significantly during the transition from free-living (egg, L3 and xL3) to parasitic (L4 and adult) stages. The three main changes observed were: (i) decreased synthesis of triradylglycerols; (ii) increased glycerophospholipids (predominantly glycerophosphoethanolamines and glycerophosphocholines); and (iii) a 'cooperative' modulation of ether-linked lipids and saturated fatty acids. These changes suggest specific adaptations, in terms of nutrient acquisition, metabolism and development, as the nematode makes its transition to the parasitic stage inside the host animal. This lipidomic data set serves as a stimulus for studies to understand lipid biology in parasitic worms, and their roles in parasite-host interactions and disease processes.
-
understanding Haemonchus contortus better through genomics and transcriptomics
Advances in Parasitology, 2016Co-Authors: Robin B Gasser, Pasi K Korhonen, Erich M Schwarz, Neil D YoungAbstract:Parasitic roundworms (nematodes) cause substantial mortality and morbidity in animals globally. The barber's pole worm, Haemonchus contortus, is one of the most economically significant parasitic nematodes of small ruminants worldwide. Although this and related nematodes can be controlled relatively well using anthelmintics, resistance against most drugs in common use has become a major problem. Until recently, almost nothing was known about the molecular biology of H. contortus on a global scale. This chapter gives a brief background on H. contortus and haemonchosis, immune responses, vaccine research, chemotherapeutics and current problems associated with drug resistance. It also describes progress in transcriptomics before the availability of H. contortus genomes and the challenges associated with such work. It then reviews major progress on the two draft genomes and developmental transcriptomes of H. contortus, and summarizes their implications for the molecular biology of this worm in both the free-living and the parasitic stages of its life cycle. The chapter concludes by considering how genomics and transcriptomics can accelerate research on Haemonchus and related parasites, and can enable the development of new interventions against haemonchosis.
-
first report of anthelmintic resistance in Haemonchus contortus in alpacas in australia
Parasites & Vectors, 2013Co-Authors: Abdul Jabbar, Angus J D Campbell, J A Charles, Robin B GasserAbstract:Parasitic nematodes can cause substantial clinical and subclinical problems in alpacas and anthelmintics are regularly used to control parasitic nematodes in alpacas. Although anthelmintic resistance has been reported in ruminants worldwide, very little is known about anthelmintic resistance in alpacas. The present study was carried out to confirm a suspected case of anthelmintic resistance in Haemonchus contortus in alpacas in Australia. Post mortem examination of an alpaca was conducted to determine the cause of its death. To confirm a suspected case of macrocyclic lactone (ML) resistance in H. contortus in alpacas, a faecal egg count reduction test (FECRT) was performed using closantel (7.5 mg/kg) and ivermectin (0.2 mg/kg). Nematode species were identified by morphological and molecular methods. Post mortem examination of a 1-year-old female alpaca that had died following a brief period of lethargy, anorexia and recumbency revealed severe anaemia, hypoproteinaemia and gastric parasitism by adult Haemonchus contortus, despite recent abamectin (0.2 mg/kg) treatment. Based on these findings and the exclusive use of MLs in the herd over the preceding six years, ML resistance in parasitic nematodes of alpacas on this farm was suspected. FECRT revealed that the efficacy of closantel was 99% (95% CI 93-100), whereas that of ivermectin was 35% (95% CI 0-78), indicating that the treatment failure was likely due to the presence of ML-resistant nematodes. Larval culture of faecal samples collected following ivermectin treatment consisted of 99% H. contortus and 1% Cooperia oncophora, a result confirmed using a PCR assay. This study provides the first evidence of ML resistance in H. contortus in alpacas in Australia. Based on the extent of anthelmintic resistance in sheep gastrointestinal nematodes in Australia, veterinarians and alpaca owners should be encouraged to implement integrated parasite management strategies to improve nematode control in alpacas.
Aguilar Marcelino Liliana - One of the best experts on this subject based on the ideXlab platform.
-
Microorganismos con uso potencial contra el nematodo de ovinos Haemonchus contortus.
Colegio de Postgraduados (COLPOS), 2012Co-Authors: Aguilar Marcelino LilianaAbstract:La presente investigación tuvo como objetivo general evaluar la actividad antagónica de microorganismos con uso potencial contra el parásito de ovinos Haemonchus contortus. Esta investigación constó de cuatro estudios. En el primer estudio se obtuvo e identificó morfológica y molecularmente el aislamiento de una bacteria a partir de nematodos fitopatógenos. Los resultados obtenidos del análisis molecular mostraron un 95% de similitud con la región 16S rRNA de la bacteria Comamonas aquatica. A pesar de que los iniciadores utilizados en el presente estudio fueron específicos para Pasteuria-like, los antecedentes de esta bacteria al parecer no tienen relación con ninguna actividad antagónica en contra de nematodos; y regularmente no produce esporas. Por lo que el hecho de que las esporas adheridas a la cutícula de los nematodos correspondan o no a C. aquatica queda sin aclarar. Los resultados son considerados como inconsistentes; por lo que estudios posteriores como por ejemplo clonación del cDNA de la bacteria Pasteuria-like y otras pruebas moleculares utilizando a la bacteria Pasteuria-like como control positivo; además de técnicas complementarias de microscopía electrónica de barrido y de transmisión deberán ser llevadas a cabo de manera complementaria para estar completamente seguros de la correcta identificación de este microorganismo.Por otra parte, se evaluó la actividad de adosamiento in vitro de esporas de la bacteria Pasteuria-like (P-l) en contra de diversos estadios de desarrollo de Haemonchus contortus; además de los nematodos Meloidogyne spp. (J2) y Rhabditis sp. Los resultados mostraron los siguientes porcentajes de adhesión: para huevos de H. contortus=0%; L1=12%; L2=20%; L3=4%, L4=40%; para Rhabditis sp.=4% y Meloidogyne spp.=28%. Por primera vez se reporta el hallazgo de la presencia de esporas bacterianas adosadas a la pared cuticular del tercer estadio de desarrollo H. contortus. En el segundo estudio, se evaluó la actividad del ácaro Lasioseius penicilliger en contra de H.contortus (L3), Rhabditis sp. y Panagrellus redivivus. Los resultados mostraron porcentajes de reducción de 79.5% para H. contortus, 64.3% para P. redivivus y 80.7% para Rhabditis sp. Este resultado podría tener una implicación potencial en el empleo de ácaros de esta especie en el control de nematodos parásitos de importancia pecuaria. Se reporta por primera vez la actividad depredadora del ácaro L. penicilliger en contra de un nematodo parásito de animales. En el tercer estudio se evaluó el efecto depredador in vitro del nematodo Butlerius sp. en contra de tres diferentes nematodos: Haemonchus contortus (L3), Panagrellus redivivus y Rhabditis sp. La interacción entre Butlerius y H. contortus; resultó en una reducción de 91.8% de la población del parásito; mientras que la población de Butlerius se incrementó 131.6 veces. Para el caso de la interacción entre Butlerius y P. redivivus; la población del nematodo de vida libre se redujo en 80.9%; mientras que el nematodo depredador se incrementó 268.3 veces. La reducción de Rhabditis por acción del nematodo depredador fue de 62.5%; mientras que, el nematodo Butlerius se incrementó 82.7 veces. El nematodo Butlerius sp. mostró ser un eficiente antagonista natural de larvas infectantes del nematodo H. contortus. En el cuarto estudio se evaluó el efecto de la suplementación de comprimidos multinutricionales conteniendo clamidosporas del hongo Duddingtonia flagrans en ovinos de la raza Santa Cruz sobre la población de larvas de H. contortus en heces y sobre la ganancia de peso. Los resultados mostraron una reducción en la población de larvas infectantes de H. contortus en cultivos fecales de los ovinos suplementados con los comprimidos multinutricionales (CM) en un rango de 42.1-84.3% durante 11 semanas que duró el experimento, excepto en el 3er y 4to muestreo. La ganancia de peso diaria fue muy similar en ambos grupos de ovinos; siendo 136 g para el grupo suplementados con alimento comercial para ovinos y 163 g para el grupo suplementado con CM conteniendo clamidosporas del hongo D. flagrans. Con respecto al parámetro de volumen celular aglomerado, el grupo suplementado con CM mostró valores ligeramente más bajos que el grupo con alimento comercial para ovinos; sin embargo, la ganancia de peso no se vio afectada. El parámetro de condición corporal fue muy similar en ambos grupos. Respecto a la viabilidad de las clamidosporas de D. flagrans in vitro después de su paso a través del tracto digestivo de los ovinos, se observó en las placas de agar adicionadas con heces de los animales la formación y presencia de redes tridimensionales del hongo mostrando la presencia de nematodos atrapados. En esta investigación se concluye que los microorganismos evaluados actúan como antagonistas de H. contortus y podrían ser utilizados en futuros estudios para determinar su potencial antagónico en contra de la hemoncosis y de otras enfermedades causadas por nematodos de importancia en la industria ovina. _______________ ABSTRACT: This research was aimed to evaluate the antagonistic activity of microorganisms with potential use against the sheep parasitic nematode Haemonchus contortus. The work was divided into four studies. In the first one, the isolation of a bacterium attached to phytopathogenic nematodes followed by its morphological and molecular identification was achieved. Results of the molecular analysis showed 95% alignment with the 16S rRNA region of the bacterium Comamonas aquatica. Although, the primers used in the present study were specific for Pasteuria-like bacteria, the background of this bacterium seems to have no relationship to any antagonistic activity against nematodes also; and no spores are regularly produced by this microorganism. So, it was unclear wether the spores attached to the nematode cuticle corresponded or not to C. aquatica. Such results are considered inconclusive and further studies ie., cDNA cloning of the bacterium and molecular assays using DNA of Pasteuria-like as a positive control and also the use of scanning and transmission electronic microscopy complementary techniques should be performed to be completely sure about the identification of this microorganism. However, the in vitro Pasteuria-like (P-l) spore attachment was also evaluated against various developmental stages of Haemonchus contortus, Meloidogyne spp. (J2) and Rhabditis sp. The results showed the following attachment percentages: H. contortus eggs=0%; L1= 12%; L2=20%; L3=4%, L4=40%; for Rhabditis sp. =4% and for Meloidogyne spp. =28%. For the first time, the presence of spores of a bacterium attached to the cuticle of the third larval stage of H. contortus has been recorded. In the second study, the predatory activity of the mite Lasioseius penicilliger against H. contortus (L3), Rhabditis sp. and Panagrellus redivivus, was evaluated. The results showed the following reduction percentages: 79.5% for H. contortus, 64.3% for P. redivivus and 80.7% for Rhabditis sp. This is the first record of the predatory activity of the mite L. penicilliger against a parasitic nematode of sheep.This result has potential for exploitation of the use of mites of this species for the control of parasitic nematodes affecting sheep. In the third study, the in vitro predatory activity of the nematode Butlerius sp. against three different nematodes: Haemonchus contortus (L3), Panagrellus redivivus and Rhabditis sp. was evaluated. The interaction between Butlerius sp. and H. contortus resulted in 91.8% reduction in the population of the parasite; meanwhile, the Butlerius sp. population increased by 131.6-folds. Regarding the interaction between Butlerius sp.and P. redivivus, the population of the free-living nematode was reduced to 80.9%; meanwhile the population of the predatory nematode was increased 268.3-folds. On the other hand, the Rhabditis sp. population was decreased to 62.5% and Butlerius sp. population increased 82.7-folds. Butlerius sp. proved to be an efficient natural antagonist of H. contortus infective larvae. In the fourth study, the effect of supplying multinutritional pellets (MP) containing Duddingtonia flagrans chlamydospores on the reduction of the population of the parasitic nematode Haemonchus contortus in feces of St. Croix sheep, and on the daily weight gaining, was evaluated. The results showed a significant reduction of the infective stages of the parasite in fecal cultures of MP-supplied sheep ranging from 42.1-84.3% during the whole experiment, with exception of the third and fourth sampling. Daily weight gain was very similar in both MP-supplied (136 g) and MP-non-supplied (164 g) groups of sheep. The cell blood package values in the MP-supplied group were slightly lower than values in the control group supplied with sheep commercial food. However, daily weight gain was not affected. Likewise, body condition parameter in the two groups of sheep was very similar. Regarding the in vitro viability of D. flagrans spores after passing through the digestive tract of the sheep, the presence of tri-dimensional traps and trapped nematodes on agar plates added with the animal feces were observed. The results obtained in the present research work lead to the conclusion that the assessed microorganisms act as efficient natural antagonists of H. contortus infective larvae and that they could be used in further works to determine their antagonistic potential against sheep haemonchosis and other diseases caused by nematodes of importance in the sheep industry
-
Microorganismos con uso potencial contra el nematodo de ovinos Haemonchus contortus.
Colegio de Postgraduados (COLPOS), 2012Co-Authors: Aguilar Marcelino LilianaAbstract:La presente investigación tuvo como objetivo general evaluar la actividad antagónica de microorganismos con uso potencial contra el parásito de ovinos Haemonchus contortus. Esta investigación constó de cuatro estudios. En el primer estudio se obtuvo e identificó morfológica y molecularmente el aislamiento de una bacteria a partir de nematodos fitopatógenos. Los resultados obtenidos del análisis molecular mostraron un 95% de similitud con la región 16S rRNA de la bacteria Comamonas aquatica. A pesar de que los iniciadores utilizados en el presente estudio fueron específicos para Pasteuria-like, los antecedentes de esta bacteria al parecer no tienen relación con ninguna actividad antagónica en contra de nematodos; y regularmente no produce esporas. Por lo que el hecho de que las esporas adheridas a la cutícula de los nematodos correspondan o no a C. aquatica queda sin aclarar. Los resultados son considerados como inconsistentes; por lo que estudios posteriores como por ejemplo clonación del cDNA de la bacteria Pasteuria-like y otras pruebas moleculares utilizando a la bacteria Pasteuria-like como control positivo; además de técnicas complementarias de microscopía electrónica de barrido y de transmisión deberán ser llevadas a cabo de manera complementaria para estar completamente seguros de la correcta identificación de este microorganismo.Por otra parte, se evaluó la actividad de adosamiento in vitro de esporas de la bacteria Pasteuria-like (P-l) en contra de diversos estadios de desarrollo de Haemonchus contortus; además de los nematodos Meloidogyne spp. (J2) y Rhabditis sp. Los resultados mostraron los siguientes porcentajes de adhesión: para huevos de H. contortus=0%; L1=12%; L2=20%; L3=4%, L4=40%; para Rhabditis sp.=4% y Meloidogyne spp.=28%. Por primera vez se reporta el hallazgo de la presencia de esporas bacterianas adosadas a la pared cuticular del tercer estadio de desarrollo H. contortus. En el segundo estudio, se evaluó la actividad del ácaro Lasioseius penicilliger en contra de H.contortus (L3), Rhabditis sp. y Panagrellus redivivus. Los resultados mostraron porcentajes de reducción de 79.5% para H. contortus, 64.3% para P. redivivus y 80.7% para Rhabditis sp. Este resultado podría tener una implicación potencial en el empleo de ácaros de esta especie en el control de nematodos parásitos de importancia pecuaria. Se reporta por primera vez la actividad depredadora del ácaro L. penicilliger en contra de un nematodo parásito de animales. En el tercer estudio se evaluó el efecto depredador in vitro del nematodo Butlerius sp. en contra de tres diferentes nematodos: Haemonchus contortus (L3), Panagrellus redivivus y Rhabditis sp. La interacción entre Butlerius y H. contortus; resultó en una reducción de 91.8% de la población del parásito; mientras que la población de Butlerius se incrementó 131.6 veces. Para el caso de la interacción entre Butlerius y P. redivivus; la población del nematodo de vida libre se redujo en 80.9%; mientras que el nematodo depredador se incrementó 268.3 veces. La reducción de Rhabditis por acción del nematodo depredador fue de 62.5%; mientras que, el nematodo Butlerius se incrementó 82.7 veces. El nematodo Butlerius sp. mostró ser un eficiente antagonista natural de larvas infectantes del nematodo H. contortus. En el cuarto estudio se evaluó el efecto de la suplementación de comprimidos multinutricionales conteniendo clamidosporas del hongo Duddingtonia flagrans en ovinos de la raza Santa Cruz sobre la población de larvas de H. contortus en heces y sobre la ganancia de peso. Los resultados mostraron una reducción en la población de larvas infectantes de H. contortus en cultivos fecales de los ovinos suplementados con los comprimidos multinutricionales (CM) en un rango de 42.1-84.3% durante 11 semanas que duró el experimento, excepto en el 3er y 4to muestreo. La ganancia de peso diaria fue muy similar en ambos grupos de ovinos; siendo 136 g para el grupo suplementados con alimento comercial para ovinos y 163 g para el grupo suplementado con CM conteniendo clamidosporas del hongo D. flagrans. Con respecto al parámetro de volumen celular aglomerado, el grupo suplementado con CM mostró valores ligeramente más bajos que el grupo con alimento comercial para ovinos; sin embargo, la ganancia de peso no se vio afectada. El parámetro de condición corporal fue muy similar en ambos grupos. Respecto a la viabilidad de las clamidosporas de D. flagrans in vitro después de su paso a través del tracto digestivo de los ovinos, se observó en las placas de agar adicionadas con heces de los animales la formación y presencia de redes tridimensionales del hongo mostrando la presencia de nematodos atrapados. En esta investigación se concluye que los microorganismos evaluados actúan como antagonistas de H. contortus y podrían ser utilizados en futuros estudios para determinar su potencial antagónico en contra de la hemoncosis y de otras enfermedades causadas por nematodos de importancia en la industria ovina. _______________ ABSTRACT: This research was aimed to evaluate the antagonistic activity of microorganisms with potential use against the sheep parasitic nematode Haemonchus contortus. The work was divided into four studies. In the first one, the isolation of a bacterium attached to phytopathogenic nematodes followed by its morphological and molecular identification was achieved. Results of the molecular analysis showed 95% alignment with the 16S rRNA region of the bacterium Comamonas aquatica. Although, the primers used in the present study were specific for Pasteuria-like bacteria, the background of this bacterium seems to have no relationship to any antagonistic activity against nematodes also; and no spores are regularly produced by this microorganism. So, it was unclear wether the spores attached to the nematode cuticle corresponded or not to C. aquatica. Such results are considered inconclusive and further studies ie., cDNA cloning of the bacterium and molecular assays using DNA of Pasteuria-like as a positive control and also the use of scanning and transmission electronic microscopy complementary techniques should be performed to be completely sure about the identification of this microorganism. However, the in vitro Pasteuria-like (P-l) spore attachment was also evaluated against various developmental stages of Haemonchus contortus, Meloidogyne spp. (J2) and Rhabditis sp. The results showed the following attachment percentages: H. contortus eggs=0%; L1= 12%; L2=20%; L3=4%, L4=40%; for Rhabditis sp. =4% and for Meloidogyne spp. =28%. For the first time, the presence of spores of a bacterium attached to the cuticle of the third larval stage of H. contortus has been recorded. In the second study, the predatory activity of the mite Lasioseius penicilliger against H. contortus (L3), Rhabditis sp. and Panagrellus redivivus, was evaluated. The results showed the following reduction percentages: 79.5% for H. contortus, 64.3% for P. redivivus and 80.7% for Rhabditis sp. This is the first record of the predatory activity of the mite L. penicilliger against a parasitic nematode of sheep.This result has potential for exploitation of the use of mites of this species for the control of parasitic nematodes affecting sheep. In the third study, the in vitro predatory activity of the nematode Butlerius sp. against three different nematodes: Haemonchus contortus (L3), Panagrellus redivivus and Rhabditis sp. was evaluated. The interaction between Butlerius sp. and H. contortus resulted in 91.8% reduction in the population of the parasite; meanwhile, the Butlerius sp. population increased by 131.6-folds. Regarding the interaction between Butlerius sp.and P. redivivus, the population of the free-living nematode was reduced to 80.9%; meanwhile the population of the predatory nematode was increased 268.3-folds. On the other hand, the Rhabditis sp. population was decreased to 62.5% and Butlerius sp. population increased 82.7-folds. Butlerius sp. proved to be an efficient natural antagonist of H. contortus infective larvae. In the fourth study, the effect of supplying multinutritional pellets (MP) containing Duddingtonia flagrans chlamydospores on the reduction of the population of the parasitic nematode Haemonchus contortus in feces of St. Croix sheep, and on the daily weight gaining, was evaluated. The results showed a significant reduction of the infective stages of the parasite in fecal cultures of MP-supplied sheep ranging from 42.1-84.3% during the whole experiment, with exception of the third and fourth sampling. Daily weight gain was very similar in both MP-supplied (136 g) and MP-non-supplied (164 g) groups of sheep. The cell blood package values in the MP-supplied group were slightly lower than values in the control group supplied with sheep commercial food. However, daily weight gain was not affected. Likewise, body condition parameter in the two groups of sheep was very similar. Regarding the in vitro viability of D. flagrans spores after passing through the digestive tract of the sheep, the presence of tri-dimensional traps and trapped nematodes on agar plates added with the animal feces were observed. The results obtained in the present research work lead to the conclusion that the assessed microorganisms act as efficient natural antagonists of H. contortus infective larvae and that they could be used in further works to determine their antagonistic potential against sheep haemonchosis and other diseases caused by nematodes of importance in the sheep industry.Tesis (Doctorado en Ciencias, especialista en Ganadería).- Colegio de Postgraduados, 2012.Consejo Nacional de Ciencia y Tecnología (CONACyT). Proyecto SAGARPA-CONACYT
Christian Heim - One of the best experts on this subject based on the ideXlab platform.
-
RESEARCH Open Access Inhibition of Haemonchus contortus larval development by fungal lectins
2016Co-Authors: Christian Heim, Hubertus Hertzberg, Alex Butschi, Silvia Bleuler-martinez, Markus Aebi, Peter Deplazes, Markus Künzler, Saša ŠtefanićAbstract:Background: Lectins are carbohydrate-binding proteins that are involved in fundamental intra- and extracellular biological processes. They occur ubiquitously in nature and are especially abundant in plants and fungi. It has been well established that certain higher fungi produce lectins in their fruiting bodies and/or sclerotia as a part of their natural resistance against free-living fungivorous nematodes and other pests. Despite relatively high diversity of the glycan structures in nature, many of the glycans targeted by fungal lectins are conserved among organisms of the same taxon and sometimes even among different taxa. Such conservation of glycans between free-living and parasitic nematodes is providing us with a useful tool for discovery of novel chemotherapeutic and vaccine targets. In our study, a subset of fungal lectins emanating from toxicity screens on Caenorhabditis elegans was tested for their potential to inhibit larval development of Haemonchus contortus. Methods: The effect of Coprinopsis cinerea lectins- CCL2, CGL2, CGL3; Aleuria aurantia lectin – AAL; Marasmius oreades agglutinin- MOA; and Laccaria bicolor lectin – Lb-Tec2, on cultivated Haemonchus contortus larval stages was investigated using a larval development test (LDT). To validate the results of the toxicity assay and determine lectin binding capacity to the nematode digestive tract, biotinylated versions of lectins were fed to pre-infective larval stages of H. contortus and visualized by fluorescent microscopy. Lectin histochemistry on fixed adult worms was performed t
-
Inhibition of Haemonchus contortus larval development by fungal lectins
Parasites & Vectors, 2015Co-Authors: Christian Heim, Hubertus Hertzberg, Alex Butschi, Silvia Bleuler-martinez, Markus Aebi, Peter Deplazes, Markus Künzler, Saša ŠtefanićAbstract:Background Lectins are carbohydrate-binding proteins that are involved in fundamental intra- and extracellular biological processes. They occur ubiquitously in nature and are especially abundant in plants and fungi. It has been well established that certain higher fungi produce lectins in their fruiting bodies and/or sclerotia as a part of their natural resistance against free-living fungivorous nematodes and other pests. Despite relatively high diversity of the glycan structures in nature, many of the glycans targeted by fungal lectins are conserved among organisms of the same taxon and sometimes even among different taxa. Such conservation of glycans between free-living and parasitic nematodes is providing us with a useful tool for discovery of novel chemotherapeutic and vaccine targets. In our study, a subset of fungal lectins emanating from toxicity screens on Caenorhabditis elegans was tested for their potential to inhibit larval development of Haemonchus contortus . Methods The effect of Coprinopsis cinerea lectins - CCL2, CGL2, CGL3; Aleuria aurantia lectin – AAL; Marasmius oreades agglutinin - MOA; and Laccaria bicolor lectin – Lb-Tec2, on cultivated Haemonchus contortus larval stages was investigated using a larval development test (LDT). To validate the results of the toxicity assay and determine lectin binding capacity to the nematode digestive tract, biotinylated versions of lectins were fed to pre-infective larval stages of H. contortus and visualized by fluorescent microscopy. Lectin histochemistry on fixed adult worms was performed to investigate the presence and localisation of lectin binding sites in the disease-relevant developmental stage. Results Using an improved larval development test we found that four of the six tested lectins: AAL, CCL2, MOA and CGL2, exhibited a dose-dependent toxicity in LDT, as measured by the number of larvae developing to the L3 stage. In the case of AAL, CGL2 and MOA lectin, doses as low as 5 μg/ml caused >95 % inhibition of larval development while 40 μg/ml were needed to achieve the same inhibition by CCL2 lectin. MOA was the only lectin tested that caused larval death while other toxic lectins had larvistatic effect manifesting as L1 growth arrest. Using lectin histochemistry we demonstrate that of all lectins tested, only the four toxic ones displayed binding to the larvae’s gut and likewise were found to interact with glycans localized to the gastrodermal tissue of adults. Conclusion The results of our study suggest a correlation between the presence of target glycans of lectins in the digestive tract and the lectin-mediated toxicity in Haemonchus contortus . We demonstrate that binding to the structurally conserved glycan structures found in H. contortus gastrodermal tissue by the set of fungal lectins has detrimental effect on larval development. Some of these glycan structures might represent antigens which are not exposed to the host immune system (hidden antigens) and thus have a potential for vaccine or drug development. Nematotoxic fungal lectins prove to be a useful tool to identify such targets in parasitic nematodes.
-
inhibition of Haemonchus contortus larval development by fungal lectins
Parasites & Vectors, 2015Co-Authors: Christian Heim, Hubertus Hertzberg, Alex Butschi, Markus Aebi, Peter Deplazes, Markus Künzler, Silvia Bleulermartinez, Sasa StefanicAbstract:Background Lectins are carbohydrate-binding proteins that are involved in fundamental intra- and extracellular biological processes. They occur ubiquitously in nature and are especially abundant in plants and fungi. It has been well established that certain higher fungi produce lectins in their fruiting bodies and/or sclerotia as a part of their natural resistance against free-living fungivorous nematodes and other pests. Despite relatively high diversity of the glycan structures in nature, many of the glycans targeted by fungal lectins are conserved among organisms of the same taxon and sometimes even among different taxa. Such conservation of glycans between free-living and parasitic nematodes is providing us with a useful tool for discovery of novel chemotherapeutic and vaccine targets. In our study, a subset of fungal lectins emanating from toxicity screens on Caenorhabditis elegans was tested for their potential to inhibit larval development of Haemonchus contortus.
Aaron R Jex - One of the best experts on this subject based on the ideXlab platform.
-
Using 454 technology for long-PCR based sequencing of the complete mitochondrial genome from single Haemonchus contortus (Nematoda)
'Springer Science and Business Media LLC', 2020Co-Authors: Aaron R Jex, Hu M, Littlewood T, Waeschenbach A, Rb GasserAbstract:Background: Mitochondrial (mt) genomes represent a rich source of molecular markers for a range of applications, including population genetics, systematics, epidemiology and ecology. In the present study, we used 454 technology (or the GS20, massively parallel picolitre reactor platform) to determine the complete mt genome of Haemonchus contortus (Nematoda: Trichostrongylidae), a parasite of substantial agricultural, veterinary and economic significance. We validate this approach by comparison with mt sequences from publicly available expressed sequence tag (EST) and genomic survey sequence (GSS) data sets. Results: The complete mt genome of Haemonchus contortus was sequenced directly from longPCR amplified template utilizing genomic DNA (~20–40 ng) from a single adult male using 454 technology. A single contig was assembled and compared against mt sequences mined from publicly available EST (NemBLAST) and GSS datasets. The comparison demonstrated that the 454 technology platform is reliable for the sequencing of AT-rich mt genomes from nematodes. The mt genome sequenced for Haemonchus contortus was 14,055 bp in length and was highly AT-rich (78.1%). In accordance with other chromadorean nematodes studied to date, the mt genome of H. contortus contained 36 genes (12 protein coding, 22 tRNAs, rrnL and rrnS) and was similar in structure, size and gene arrangement to those characterized previously for members of the Strongylida. Conclusion: The present study demonstrates the utility of 454 technology for the rapid determination of mt genome sequences from tiny amounts of DNA and reveals a wealth of mt genomic data in current databases available for mining. This approach provides a novel platform for high-throughput sequencing of mt genomes from nematodes and other organisms.© 2008 Jex et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
-
using 454 technology for long pcr based sequencing of the complete mitochondrial genome from single Haemonchus contortus nematoda
BMC Genomics, 2008Co-Authors: Aaron R Jex, Timothy D J Littlewood, Andrea Waeschenbach, Robin B GasserAbstract:Mitochondrial (mt) genomes represent a rich source of molecular markers for a range of applications, including population genetics, systematics, epidemiology and ecology. In the present study, we used 454 technology (or the GS20, massively parallel picolitre reactor platform) to determine the complete mt genome of Haemonchus contortus (Nematoda: Trichostrongylidae), a parasite of substantial agricultural, veterinary and economic significance. We validate this approach by comparison with mt sequences from publicly available expressed sequence tag (EST) and genomic survey sequence (GSS) data sets. The complete mt genome of Haemonchus contortus was sequenced directly from long-PCR amplified template utilizing genomic DNA (~20–40 ng) from a single adult male using 454 technology. A single contig was assembled and compared against mt sequences mined from publicly available EST (NemBLAST) and GSS datasets. The comparison demonstrated that the 454 technology platform is reliable for the sequencing of AT-rich mt genomes from nematodes. The mt genome sequenced for Haemonchus contortus was 14,055 bp in length and was highly AT-rich (78.1%). In accordance with other chromadorean nematodes studied to date, the mt genome of H. contortus contained 36 genes (12 protein coding, 22 tRNAs, rrnL and rrnS) and was similar in structure, size and gene arrangement to those characterized previously for members of the Strongylida. The present study demonstrates the utility of 454 technology for the rapid determination of mt genome sequences from tiny amounts of DNA and reveals a wealth of mt genomic data in current databases available for mining. This approach provides a novel platform for high-throughput sequencing of mt genomes from nematodes and other organisms.
Saša Štefanić - One of the best experts on this subject based on the ideXlab platform.
-
RESEARCH Open Access Inhibition of Haemonchus contortus larval development by fungal lectins
2016Co-Authors: Christian Heim, Hubertus Hertzberg, Alex Butschi, Silvia Bleuler-martinez, Markus Aebi, Peter Deplazes, Markus Künzler, Saša ŠtefanićAbstract:Background: Lectins are carbohydrate-binding proteins that are involved in fundamental intra- and extracellular biological processes. They occur ubiquitously in nature and are especially abundant in plants and fungi. It has been well established that certain higher fungi produce lectins in their fruiting bodies and/or sclerotia as a part of their natural resistance against free-living fungivorous nematodes and other pests. Despite relatively high diversity of the glycan structures in nature, many of the glycans targeted by fungal lectins are conserved among organisms of the same taxon and sometimes even among different taxa. Such conservation of glycans between free-living and parasitic nematodes is providing us with a useful tool for discovery of novel chemotherapeutic and vaccine targets. In our study, a subset of fungal lectins emanating from toxicity screens on Caenorhabditis elegans was tested for their potential to inhibit larval development of Haemonchus contortus. Methods: The effect of Coprinopsis cinerea lectins- CCL2, CGL2, CGL3; Aleuria aurantia lectin – AAL; Marasmius oreades agglutinin- MOA; and Laccaria bicolor lectin – Lb-Tec2, on cultivated Haemonchus contortus larval stages was investigated using a larval development test (LDT). To validate the results of the toxicity assay and determine lectin binding capacity to the nematode digestive tract, biotinylated versions of lectins were fed to pre-infective larval stages of H. contortus and visualized by fluorescent microscopy. Lectin histochemistry on fixed adult worms was performed t
-
Inhibition of Haemonchus contortus larval development by fungal lectins
Parasites & Vectors, 2015Co-Authors: Christian Heim, Hubertus Hertzberg, Alex Butschi, Silvia Bleuler-martinez, Markus Aebi, Peter Deplazes, Markus Künzler, Saša ŠtefanićAbstract:Background Lectins are carbohydrate-binding proteins that are involved in fundamental intra- and extracellular biological processes. They occur ubiquitously in nature and are especially abundant in plants and fungi. It has been well established that certain higher fungi produce lectins in their fruiting bodies and/or sclerotia as a part of their natural resistance against free-living fungivorous nematodes and other pests. Despite relatively high diversity of the glycan structures in nature, many of the glycans targeted by fungal lectins are conserved among organisms of the same taxon and sometimes even among different taxa. Such conservation of glycans between free-living and parasitic nematodes is providing us with a useful tool for discovery of novel chemotherapeutic and vaccine targets. In our study, a subset of fungal lectins emanating from toxicity screens on Caenorhabditis elegans was tested for their potential to inhibit larval development of Haemonchus contortus . Methods The effect of Coprinopsis cinerea lectins - CCL2, CGL2, CGL3; Aleuria aurantia lectin – AAL; Marasmius oreades agglutinin - MOA; and Laccaria bicolor lectin – Lb-Tec2, on cultivated Haemonchus contortus larval stages was investigated using a larval development test (LDT). To validate the results of the toxicity assay and determine lectin binding capacity to the nematode digestive tract, biotinylated versions of lectins were fed to pre-infective larval stages of H. contortus and visualized by fluorescent microscopy. Lectin histochemistry on fixed adult worms was performed to investigate the presence and localisation of lectin binding sites in the disease-relevant developmental stage. Results Using an improved larval development test we found that four of the six tested lectins: AAL, CCL2, MOA and CGL2, exhibited a dose-dependent toxicity in LDT, as measured by the number of larvae developing to the L3 stage. In the case of AAL, CGL2 and MOA lectin, doses as low as 5 μg/ml caused >95 % inhibition of larval development while 40 μg/ml were needed to achieve the same inhibition by CCL2 lectin. MOA was the only lectin tested that caused larval death while other toxic lectins had larvistatic effect manifesting as L1 growth arrest. Using lectin histochemistry we demonstrate that of all lectins tested, only the four toxic ones displayed binding to the larvae’s gut and likewise were found to interact with glycans localized to the gastrodermal tissue of adults. Conclusion The results of our study suggest a correlation between the presence of target glycans of lectins in the digestive tract and the lectin-mediated toxicity in Haemonchus contortus . We demonstrate that binding to the structurally conserved glycan structures found in H. contortus gastrodermal tissue by the set of fungal lectins has detrimental effect on larval development. Some of these glycan structures might represent antigens which are not exposed to the host immune system (hidden antigens) and thus have a potential for vaccine or drug development. Nematotoxic fungal lectins prove to be a useful tool to identify such targets in parasitic nematodes.
