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J Barrett - One of the best experts on this subject based on the ideXlab platform.

  • characterisation and properties of an intracellular lipid binding protein from the tapeworm Moniezia expansa
    FEBS Journal, 1997
    Co-Authors: J Barrett, Nahid Saghir, Katie Clarke, Anna Timanova, Peter M. Brophy
    Abstract:

    The tapeworm Moniezia expansa contains an extremely abundant cytoplasmic lipid-binding protein (LBP). It is a small protein consisting of 66 amino acids with a molecular mass of 7943 ± 1.5Da. The amino acid sequence has been established by Edman degradation and confirmed by PCR analysis. The Moniezia LBP shows no sequence similarity with any previously described binding protein, but does show similarity with antigen B from Echinococcus glanulosus and Echinococcus multilocularis and with Taenia crassiceps antigen. The predicted structure for Moniezia LBP shows four helices and a putative tyrosine kinase site on the loop between helix 1 and 2. Each of the four helices has a well defined hydrophobic face. Studies with fluorescent probes suggest a single hydrophobic binding site. Results indicate that the single tryptophan residue in the molecule (Trp41) is involved in ligand binding, and calculation of the Stern-Volmer quenching constant shows that Trp41 is in a relatively hydrophobic environment.

  • Characterisation and Properties of an Intracellular Lipid‐Binding Protein from the Tapeworm Moniezia expansa
    FEBS Journal, 1997
    Co-Authors: J Barrett, Nahid Saghir, Katie Clarke, Anna Timanova, Peter M. Brophy
    Abstract:

    The tapeworm Moniezia expansa contains an extremely abundant cytoplasmic lipid-binding protein (LBP). It is a small protein consisting of 66 amino acids with a molecular mass of 7943 ± 1.5Da. The amino acid sequence has been established by Edman degradation and confirmed by PCR analysis. The Moniezia LBP shows no sequence similarity with any previously described binding protein, but does show similarity with antigen B from Echinococcus glanulosus and Echinococcus multilocularis and with Taenia crassiceps antigen. The predicted structure for Moniezia LBP shows four helices and a putative tyrosine kinase site on the loop between helix 1 and 2. Each of the four helices has a well defined hydrophobic face. Studies with fluorescent probes suggest a single hydrophobic binding site. Results indicate that the single tryptophan residue in the molecule (Trp41) is involved in ligand binding, and calculation of the Stern-Volmer quenching constant shows that Trp41 is in a relatively hydrophobic environment.

  • a novel lipid binding protein from the cestode Moniezia expansa
    Biochemical Journal, 1995
    Co-Authors: D Janssen, J Barrett
    Abstract:

    A lipid-binding protein (LBP) has been purified from the cytosol of the cestode Moniezia expansa. The native LBP was found to be an oligomer of approx. 250 kDa, consisting of 11 kDa monomers. The LBP bound saturated and unsaturated fatty acids, but not their CoA derivatives, with KD values in the range 0.68-7.8 microM. Cholesterol, dihydroergosterol, bilirubin and retinoids were also bound, but alpha-tocopherol, bile acids, alk-2-enals and alka-2,4-dienals were not. Evidence suggests that there are two binding sites per subunit, each with different specificities. The fluorescent fatty acid 11-[(5-dimethylaminonaphthalene-1-sulphonyl)amino]undecanoic acid (DAUDA) and retinol both showed an additional high-affinity binding site with a density of approximately 0.1 per subunit, suggesting specific binding to the oligomer. The amino acid composition of Moniezia LBP was distinct from that of previously characterized fatty acid-binding proteins (FABPs). The protein was not N-terminally blocked and yielded a unique amino acid sequence, unrelated to that of any known FABP; there was also evidence of microheterogeneity. Polyclonal antibodies raised to the Moniezia protein did not cross-react with mammalian, nematode or digenean FABP. The Gibbs free energy for protein folding (13.02 kJ/mol; 3.1 kcal/mol), determined by urea denaturation, was identical for both the native and ligand-bound Moniezia LBP. CD spectra showed that the Moniezia protein contained 36% alpha-helix and that the secondary structure underwent only minor changes on ligand binding. Moniezia LBP binds a range of anthelmintics, with KD values again in the range 0.66-7.3 microM. It is possible that, in helminths, binding proteins may play a role in determining the specificity and site of action of anthelmintics.

  • the purification and properties of glutathione reductase from the cestode Moniezia expansa
    The International Journal of Biochemistry & Cell Biology, 1995
    Co-Authors: Mora J Mccallum, J Barrett
    Abstract:

    Abstract Glutathione reductase has a central role in glutathione metabolism and as such is a potential target for chemotherapy. The aim of the work was to purify and characterise glutathione reductase from the cestode Moniezia expansa and to compare the properties of the helminth enzyme with its mammalian counterpart. The enzyme was purified by a combination of anion exchange and affinity chromatography and further characterized by chromatofocusing and gel electrophoresis. Analysis revealed a single isoenzyme of glutathione reductase in Moniezia expansa, with a pI of 5.8. The enzyme was a homodimer of native molecular weight 114 kDa, subunit weight 63 kDa. Enzyme activity was affected by buffer concentration and the presence of monovalent sodium salts. The pH optimum was 7.4 with NADPH as cofactor and 5 with NADH. The Kma for oxidized glutathione was 76 μM and for NADPH and NADH, 21 and 350 μM respectively. In addition to oxidized glutathione only the mixed disulphide between CoA and glutathione (CoASSG) showed any significant activity as substrate. The cestode enzyme was inhibited by a variety of compounds including arsonic derivatives, 2,4,6 trinitrobenzene sulfonate 1,3-bis (2-chlorethyl)-1-nitrosourea and oxidized glutathione. In conclusion the glutathione reductase of M. expansa resembles the mammalian enzyme in its general physical properties and its substrate and inhibitor profile. However, the parasite enzyme shows an unusually high activity with the mixed disulphide of coenzyme A and glutathione (CoASSG) and appears to be more sensitive to inhibition by sodium ions.

  • a novel nadph nadh dependent aldehyde reduction enzyme isolated from the tapeworm Moniezia expansa
    FEBS Letters, 1990
    Co-Authors: Peter M. Brophy, Paul Crowley, J Barrett
    Abstract:

    Abstract An aldehyde reduction enzyme has been purified from the cytosol of the tapeworm, Moniezia expansa , by chromatofocusing and Reactive-Red chromatography. The enzyme is monomeric (subunit 34 kDa) and can utilise NADH and NADPH as co-factors. Substrates of the enzyme include alkanals, alka-2,4-dienals and alk-2-enals, established secondary products of lipid peroxidation. The enzyme reduced methylglyoxal, another possible natural substrate ( M. expansa lacks glyoxalase I activity). The parasite enzyme may help form a final line of defence against cytotoxic aldehydes arising from host immune initiated lipid peroxidation.

Peter M. Brophy - One of the best experts on this subject based on the ideXlab platform.

  • Cysteine conjugate β-lyase activity in three species of parasitic helminth
    International Journal for Parasitology, 1999
    Co-Authors: Harriet J Adcock, Paul H. Teesdale-spittle, Peter M. Brophy, Lorraine D. Buckberry
    Abstract:

    Abstract Living organisms employ a variety of metabolic pathways when detoxifying xenobiotic compounds, including the formation of cysteine S- conjugates via glutathione conjugation. However, cysteine conjugate β-lyase (CCBL) catalysed β-cleavage, of certain cysteine conjugates, is known to cause cytotoxicity. This study represents the first investigation into the expression of CCBL and other associated enzymes in helminth species. A survey of the three major groups of parasitic helminths [cestodes ( Moniezia expansa ), digeneans ( Fasciola hepatica ) and nematodes ( Necator americanus , Heligmosomoides polygyrus )] has been made. The presence of CCBL enzymes within Moniezia expansa , Necator americanus and Heligmosomoides polygyrus has been established. Each species was screened for γ-glutamyl transpeptidase activity and transaminase activity towards l -aspartate, l -alanine, l -albizziin and l -phenylalanine. Aspartate and alanine aminotransferase activity were detected in all four species tested. γ-Glutamyl transpeptidase activity was only detected in Moniezia expansa and Necator americanus .

  • characterisation and properties of an intracellular lipid binding protein from the tapeworm Moniezia expansa
    FEBS Journal, 1997
    Co-Authors: J Barrett, Nahid Saghir, Katie Clarke, Anna Timanova, Peter M. Brophy
    Abstract:

    The tapeworm Moniezia expansa contains an extremely abundant cytoplasmic lipid-binding protein (LBP). It is a small protein consisting of 66 amino acids with a molecular mass of 7943 ± 1.5Da. The amino acid sequence has been established by Edman degradation and confirmed by PCR analysis. The Moniezia LBP shows no sequence similarity with any previously described binding protein, but does show similarity with antigen B from Echinococcus glanulosus and Echinococcus multilocularis and with Taenia crassiceps antigen. The predicted structure for Moniezia LBP shows four helices and a putative tyrosine kinase site on the loop between helix 1 and 2. Each of the four helices has a well defined hydrophobic face. Studies with fluorescent probes suggest a single hydrophobic binding site. Results indicate that the single tryptophan residue in the molecule (Trp41) is involved in ligand binding, and calculation of the Stern-Volmer quenching constant shows that Trp41 is in a relatively hydrophobic environment.

  • Characterisation and Properties of an Intracellular Lipid‐Binding Protein from the Tapeworm Moniezia expansa
    FEBS Journal, 1997
    Co-Authors: J Barrett, Nahid Saghir, Katie Clarke, Anna Timanova, Peter M. Brophy
    Abstract:

    The tapeworm Moniezia expansa contains an extremely abundant cytoplasmic lipid-binding protein (LBP). It is a small protein consisting of 66 amino acids with a molecular mass of 7943 ± 1.5Da. The amino acid sequence has been established by Edman degradation and confirmed by PCR analysis. The Moniezia LBP shows no sequence similarity with any previously described binding protein, but does show similarity with antigen B from Echinococcus glanulosus and Echinococcus multilocularis and with Taenia crassiceps antigen. The predicted structure for Moniezia LBP shows four helices and a putative tyrosine kinase site on the loop between helix 1 and 2. Each of the four helices has a well defined hydrophobic face. Studies with fluorescent probes suggest a single hydrophobic binding site. Results indicate that the single tryptophan residue in the molecule (Trp41) is involved in ligand binding, and calculation of the Stern-Volmer quenching constant shows that Trp41 is in a relatively hydrophobic environment.

  • a novel nadph nadh dependent aldehyde reduction enzyme isolated from the tapeworm Moniezia expansa
    FEBS Letters, 1990
    Co-Authors: Peter M. Brophy, Paul Crowley, J Barrett
    Abstract:

    Abstract An aldehyde reduction enzyme has been purified from the cytosol of the tapeworm, Moniezia expansa , by chromatofocusing and Reactive-Red chromatography. The enzyme is monomeric (subunit 34 kDa) and can utilise NADH and NADPH as co-factors. Substrates of the enzyme include alkanals, alka-2,4-dienals and alk-2-enals, established secondary products of lipid peroxidation. The enzyme reduced methylglyoxal, another possible natural substrate ( M. expansa lacks glyoxalase I activity). The parasite enzyme may help form a final line of defence against cytotoxic aldehydes arising from host immune initiated lipid peroxidation.

  • A novel NADPH/NADH-dependent aldehyde reduction enzyme isolated from the tapeworm Moniezia expansa
    FEBS Letters, 1990
    Co-Authors: Peter M. Brophy, Paul Crowley, J Barrett
    Abstract:

    Abstract An aldehyde reduction enzyme has been purified from the cytosol of the tapeworm, Moniezia expansa , by chromatofocusing and Reactive-Red chromatography. The enzyme is monomeric (subunit 34 kDa) and can utilise NADH and NADPH as co-factors. Substrates of the enzyme include alkanals, alka-2,4-dienals and alk-2-enals, established secondary products of lipid peroxidation. The enzyme reduced methylglyoxal, another possible natural substrate ( M. expansa lacks glyoxalase I activity). The parasite enzyme may help form a final line of defence against cytotoxic aldehydes arising from host immune initiated lipid peroxidation.

Aaron G. Maule - One of the best experts on this subject based on the ideXlab platform.

  • gnffrfamide a novel fmrfamide immunoreactive peptide isolated from the sheep tapeworm Moniezia expansa
    Biochemical and Biophysical Research Communications, 1993
    Co-Authors: Aaron G. Maule, C Shaw, David W. Halton, Lars Thim
    Abstract:

    Abstract The widespread distribution of FMRFamide-immunoreactivity in platyhelminth nervous systems has been demonstrated immunocytochemically. Here we report the isolation and primary structure of the first platyhelminth FMRFamide-related peptide (FaRP) from the tapeworm, Moniezia expansa. The peptide was found to have a molecular mass of 785 Da and a primary structure of Gly-Asn-Phe-Phe-Arg-Phe-NH2 (GNFFRFamide). Acid alcohol extracts of this platyhelminth contained only this single FaRP which had a phenylalanyl (F) residue in the variable position 3 from the C-terminal occupied by either methionyl (M), leucyl (L) or isoleucyl (I) residues in most other FaRPs.

  • the cholinergic serotoninergic and peptidergic components of the nervous system of Moniezia expansa cestoda cyclophyllidea
    Parasitology, 1993
    Co-Authors: Aaron G. Maule, C Shaw, David W. Halton, C F Johnston
    Abstract:

    The central (CNS) and peripheral (PNS) nervous systems of the cyclophyllidean tapeworm, Moniezia expansa, were examined for the presence of cholinergic, serotoninergic and peptidergic elements using enzyme cytochemical and immunocytochemical techniques in conjunction with light and confocal scanning laser microscopv. Cholinesterase activity and 5-hydroxytryptamine- and regulatory peptide-immunoreactivities (IRs) were localized to the nerve fibres and cell bodies of all of the major neuronal components in the CNS of the worm, including the cerebral ganglia and connecting commissure, the 10 longitudinal nerve cords and associated transverse ring commissures

Jianxin Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Immunohistochemical distribution of transforming growth factor #beta#1 in cestode {\sl Moniezia expansa} (Cestoda: Cyclophyllidea)
    2020
    Co-Authors: Changsheng Dong, Junping He, Jianxin Zhang
    Abstract:

    Using immunocytochemical technique, strept-avidin biotin complex(SABC) method and the Computer Image Analysis System (Product of Beihang University, China,CMIAS-007), we studied the distribution of transforming growth factor #beta#1(TGF#beta#1) immunoreactivity in the cestode Moniezia expansa. The mature proglottides of 5 cestode Moniezia expansa were obtained from faeces of alpacas at the Scientific Research Base of Shanxi Agricultural University, Yuci, Shanxi, China. The results showed that TGF#beta#1 immunoreactivity was abundant and wide spread in the interproglottidal glands, tegumentary epithelium, eggs and uterus. The value of optical density (OD), were 0.2705±0.0804, 0.2455±0.0417, 0.4638±0.0603, 0.0373±0.0613 respectively. Thus we can get the conclusion that TGFβ1 appeares to be widely distributed in Moniezia expansa and it may play an important role in the growth and development of the worm in the host.

  • immunohistochemical distribution of transforming growth factor beta 1 in cestode sl Moniezia expansa cestoda cyclophyllidea
    Dong wu xue bao. [Acta zoologica Sinica], 2005
    Co-Authors: Changsheng Dong, Junping He, Jianxin Zhang
    Abstract:

    Using immunocytochemical technique, strept-avidin biotin complex(SABC) method and the Computer Image Analysis System (Product of Beihang University, China,CMIAS-007), we studied the distribution of transforming growth factor #beta#1(TGF#beta#1) immunoreactivity in the cestode Moniezia expansa. The mature proglottides of 5 cestode Moniezia expansa were obtained from faeces of alpacas at the Scientific Research Base of Shanxi Agricultural University, Yuci, Shanxi, China. The results showed that TGF#beta#1 immunoreactivity was abundant and wide spread in the interproglottidal glands, tegumentary epithelium, eggs and uterus. The value of optical density (OD), were 0.2705±0.0804, 0.2455±0.0417, 0.4638±0.0603, 0.0373±0.0613 respectively. Thus we can get the conclusion that TGFβ1 appeares to be widely distributed in Moniezia expansa and it may play an important role in the growth and development of the worm in the host.

C Shaw - One of the best experts on this subject based on the ideXlab platform.

  • gnffrfamide a novel fmrfamide immunoreactive peptide isolated from the sheep tapeworm Moniezia expansa
    Biochemical and Biophysical Research Communications, 1993
    Co-Authors: Aaron G. Maule, C Shaw, David W. Halton, Lars Thim
    Abstract:

    Abstract The widespread distribution of FMRFamide-immunoreactivity in platyhelminth nervous systems has been demonstrated immunocytochemically. Here we report the isolation and primary structure of the first platyhelminth FMRFamide-related peptide (FaRP) from the tapeworm, Moniezia expansa. The peptide was found to have a molecular mass of 785 Da and a primary structure of Gly-Asn-Phe-Phe-Arg-Phe-NH2 (GNFFRFamide). Acid alcohol extracts of this platyhelminth contained only this single FaRP which had a phenylalanyl (F) residue in the variable position 3 from the C-terminal occupied by either methionyl (M), leucyl (L) or isoleucyl (I) residues in most other FaRPs.

  • the cholinergic serotoninergic and peptidergic components of the nervous system of Moniezia expansa cestoda cyclophyllidea
    Parasitology, 1993
    Co-Authors: Aaron G. Maule, C Shaw, David W. Halton, C F Johnston
    Abstract:

    The central (CNS) and peripheral (PNS) nervous systems of the cyclophyllidean tapeworm, Moniezia expansa, were examined for the presence of cholinergic, serotoninergic and peptidergic elements using enzyme cytochemical and immunocytochemical techniques in conjunction with light and confocal scanning laser microscopv. Cholinesterase activity and 5-hydroxytryptamine- and regulatory peptide-immunoreactivities (IRs) were localized to the nerve fibres and cell bodies of all of the major neuronal components in the CNS of the worm, including the cerebral ganglia and connecting commissure, the 10 longitudinal nerve cords and associated transverse ring commissures