The Experts below are selected from a list of 246 Experts worldwide ranked by ideXlab platform
Roger Schneiter - One of the best experts on this subject based on the ideXlab platform.
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Localization and functional characterization of the pathogenesis-related Proteins Rbe1p and Rbt4p in Candida albicans
2018Co-Authors: Yannick Bantel, Rabih Darwiche, Roger Schneiter, Steffen Rupp, Kai SohnAbstract:Members of the Cysteine-rich secretory Protein, Antigen 5 and Pathogenesis-related 1 (CAP) Protein superfamily are important virulence factors in fungi but remain poorly characterized on molecular level. Here, we investigate the cellular localization and molecular function of Rbe1p and Rbt4p, two CAP family members from the human pathogen Candida albicans. We unexpectedly found that Rbe1p localizes to budding sites of yeast cells in a disulfide bond-dependent manner. Furthermore, we show that Rbe1p and Rbt4p bind free cholesterol in vitro and export cholesteryl acetate in vivo. These findings suggest a previously undescribed role for Rbe1p in cell wall-associated processes and a possible connection between the virulence attributes of fungal CAP Proteins and sterol binding.
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the pathogen related yeast Protein pry1 a member of the CAP Protein superfamily is a fatty acid binding Protein
Journal of Biological Chemistry, 2017Co-Authors: Rabih Darwiche, Laurent Menesaffrane, David Gfeller, Oluwatoyin A Asojo, Roger SchneiterAbstract:Members of the CAP superfamily (cysteine-rich secretory Proteins, antigen 5, and pathogenesis-related 1 Proteins), also known as SCP superfamily (sperm-coating Proteins), have been implicated in many physiological processes, including immune defenses, venom toxicity, and sperm maturation. Their mode of action, however, remains poorly understood. Three Proteins of the CAP superfamily, Pry1, -2, and -3 (pathogen related in yeast), are encoded in the Saccharomyces cerevisiae genome. We have shown previously that Pry1 binds cholesterol in vitro and that Pry function is required for sterol secretion in yeast cells, indicating that members of this superfamily may generally bind sterols or related small hydrophobic compounds. On the other hand, tablysin-15, a CAP Protein from the horsefly Tabanus yao, has been shown to bind leukotrienes and free fatty acids in vitro Therefore, here we assessed whether the yeast Pry1 Protein binds fatty acids. Computational modeling and site-directed mutagenesis indicated that the mode of fatty acid binding is conserved between tablysin-15 and Pry1. Pry1 bound fatty acids with micromolar affinity in vitro, and its function was essential for fatty acid export in cells lacking the acyl-CoA synthetases Faa1 and Faa4. Fatty acid binding of Pry1 is independent of its CAPacity to bind sterols, and the two sterol- and fatty acid-binding sites are nonoverlapping. These results indicate that some CAP family members, such as Pry1, can bind different lipids, particularly sterols and fatty acids, at distinct binding sites, suggesting that the CAP domain may serve as a stable, secreted Protein domain that can accommodate multiple ligand-binding sites.
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the caveolin binding motif of the pathogen related yeast Protein pry1 a member of the CAP Protein superfamily is required for in vivo export of cholesteryl acetate
Journal of Lipid Research, 2014Co-Authors: Vineet Choudhary, Rabih Darwiche, David Gfeller, Vincent Zoete, Olivier Michielin, Roger SchneiterAbstract:Proteins belonging to the CAP superfamily are present in all kingdoms of life and have been implicated in different physiological processes. Their molecular mode of action, however, is poorly understood. Saccharomyces cerevisiae expresses three members of this superfamily, pathogen-related yeast (Pry)1, -2, and -3. We have recently shown that Pry function is required for the secretion of cholesteryl acetate and that Pry Proteins bind cholesterol and cholesteryl acetate, suggesting that CAP superfamily members may generally act to bind sterols or related small hydrophobic compounds. Here, we analyzed the mode of sterol binding by Pry1. Computational modeling indicates that ligand binding could occur through displacement of a relatively poorly conserved flexible loop, which in some CAP family members displays homology to the caveolin-binding motif. Point mutations within this motif abrogated export of cholesteryl acetate but did not affect binding of cholesterol. Mutations of residues located outside the caveolin-binding motif, or mutations in highly conserved putative catalytic residues had no effect on export of cholesteryl acetate or on lipid binding. These results indicate that the caveolin-binding motif of Pry1, and possibly of other CAP family members, is crucial for selective lipid binding and that lipid binding may occur through displacement of the loop containing this motif.
Jaime A Tobar - One of the best experts on this subject based on the ideXlab platform.
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the optimized CAPsid gene of porcine circovirus type 2 expressed in yeast forms virus like particles and elicits antibody responses in mice fed with recombinant yeast extracts
Vaccine, 2009Co-Authors: Sergio A Bucarey, Jorge Noriega, Paulina Reyes, Cecilia V Tapia, Leonardo Saenz, Alejandro Zuniga, Jaime A TobarAbstract:Porcine circovirus type 2 (PCV2)-associated diseases are considered to be the biggest problem for the worldwide swine industry. The PCV2 CAPsid Protein (CAP) is an important antigen for development of vaccines. At present, most anti-PCV2 vaccines are produced as injectable formulations. Although effective, these vaccines have certain drawbacks, including stress with concomitant immunosuppresion, and involve laborious and time-consuming procedures. In this study, Saccharomyces cerevisiae was used as a vehicle to deliver PCV2 antigen in a preliminary attempt to develop an oral vaccine, and its immunogenic potential in mice was tested after oral gavage-mediated delivery. The CAP gene with a yeast-optimized codon usage sequence (opt-CAP) was chemically synthesized and cloned into Escherichia coli/Saccharomyces cerevisiae shuttle vector, pYES2, under the control of the Gal1 promoter. Intracellular expression of the CAP Protein was confirmed by Western blot analysis and its antigenic properties were compared with those of baculovirus/insect cell-produced CAP Protein derived from the native PCV2 CAP gene. It was further demonstrated by electron micrography that the yeast-derived PCV2 CAP Protein self-assembles into virus-like particles (VLPs) that are morphologically and antigenically similar to insect cell-derived VLPs. Feeding raw yeast extract containing CAP Protein to mice elicited both serum- and fecal-specific antibodies against the antigen. These results show that it is feasible to use S. cerevisiae as a safe and simple system to produce PCV2 virus-like particles, and that oral yeast-mediated antigen delivery is an alternative strategy to efficiently induce anti-PCV2 antibodies in a mouse model, which is worthy of further investigation in swine.
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the optimized CAPsid gene of porcine circovirus type 2 expressed in yeast forms virus like particles and elicits antibody responses in mice fed with recombinant yeast extracts
Vaccine, 2009Co-Authors: Sergio A Bucarey, Jorge Noriega, Paulina Reyes, Cecilia V Tapia, Leonardo Saenz, Alejandro Zuniga, Jaime A TobarAbstract:Porcine circovirus type 2 (PCV2)-associated diseases are considered to be the biggest problem for the worldwide swine industry. The PCV2 CAPsid Protein (CAP) is an important antigen for development of vaccines. At present, most anti-PCV2 vaccines are produced as injectable formulations. Although effective, these vaccines have certain drawbacks, including stress with concomitant immunosuppresion, and involve laborious and time-consuming procedures. In this study, Saccharomyces cerevisiae was used as a vehicle to deliver PCV2 antigen in a preliminary attempt to develop an oral vaccine, and its immunogenic potential in mice was tested after oral gavage-mediated delivery. The CAP gene with a yeast-optimized codon usage sequence (opt-CAP) was chemically synthesized and cloned into Escherichia coli/Saccharomyces cerevisiae shuttle vector, pYES2, under the control of the Gal1 promoter. Intracellular expression of the CAP Protein was confirmed by Western blot analysis and its antigenic properties were compared with those of baculovirus/insect cell-produced CAP Protein derived from the native PCV2 CAP gene. It was further demonstrated by electron micrography that the yeast-derived PCV2 CAP Protein self-assembles into virus-like particles (VLPs) that are morphologically and antigenically similar to insect cell-derived VLPs. Feeding raw yeast extract containing CAP Protein to mice elicited both serum- and fecal-specific antibodies against the antigen. These results show that it is feasible to use S. cerevisiae as a safe and simple system to produce PCV2 virus-like particles, and that oral yeast-mediated antigen delivery is an alternative strategy to efficiently induce anti-PCV2 antibodies in a mouse model, which is worthy of further investigation in swine.
David Gfeller - One of the best experts on this subject based on the ideXlab platform.
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the pathogen related yeast Protein pry1 a member of the CAP Protein superfamily is a fatty acid binding Protein
Journal of Biological Chemistry, 2017Co-Authors: Rabih Darwiche, Laurent Menesaffrane, David Gfeller, Oluwatoyin A Asojo, Roger SchneiterAbstract:Members of the CAP superfamily (cysteine-rich secretory Proteins, antigen 5, and pathogenesis-related 1 Proteins), also known as SCP superfamily (sperm-coating Proteins), have been implicated in many physiological processes, including immune defenses, venom toxicity, and sperm maturation. Their mode of action, however, remains poorly understood. Three Proteins of the CAP superfamily, Pry1, -2, and -3 (pathogen related in yeast), are encoded in the Saccharomyces cerevisiae genome. We have shown previously that Pry1 binds cholesterol in vitro and that Pry function is required for sterol secretion in yeast cells, indicating that members of this superfamily may generally bind sterols or related small hydrophobic compounds. On the other hand, tablysin-15, a CAP Protein from the horsefly Tabanus yao, has been shown to bind leukotrienes and free fatty acids in vitro Therefore, here we assessed whether the yeast Pry1 Protein binds fatty acids. Computational modeling and site-directed mutagenesis indicated that the mode of fatty acid binding is conserved between tablysin-15 and Pry1. Pry1 bound fatty acids with micromolar affinity in vitro, and its function was essential for fatty acid export in cells lacking the acyl-CoA synthetases Faa1 and Faa4. Fatty acid binding of Pry1 is independent of its CAPacity to bind sterols, and the two sterol- and fatty acid-binding sites are nonoverlapping. These results indicate that some CAP family members, such as Pry1, can bind different lipids, particularly sterols and fatty acids, at distinct binding sites, suggesting that the CAP domain may serve as a stable, secreted Protein domain that can accommodate multiple ligand-binding sites.
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the caveolin binding motif of the pathogen related yeast Protein pry1 a member of the CAP Protein superfamily is required for in vivo export of cholesteryl acetate
Journal of Lipid Research, 2014Co-Authors: Vineet Choudhary, Rabih Darwiche, David Gfeller, Vincent Zoete, Olivier Michielin, Roger SchneiterAbstract:Proteins belonging to the CAP superfamily are present in all kingdoms of life and have been implicated in different physiological processes. Their molecular mode of action, however, is poorly understood. Saccharomyces cerevisiae expresses three members of this superfamily, pathogen-related yeast (Pry)1, -2, and -3. We have recently shown that Pry function is required for the secretion of cholesteryl acetate and that Pry Proteins bind cholesterol and cholesteryl acetate, suggesting that CAP superfamily members may generally act to bind sterols or related small hydrophobic compounds. Here, we analyzed the mode of sterol binding by Pry1. Computational modeling indicates that ligand binding could occur through displacement of a relatively poorly conserved flexible loop, which in some CAP family members displays homology to the caveolin-binding motif. Point mutations within this motif abrogated export of cholesteryl acetate but did not affect binding of cholesterol. Mutations of residues located outside the caveolin-binding motif, or mutations in highly conserved putative catalytic residues had no effect on export of cholesteryl acetate or on lipid binding. These results indicate that the caveolin-binding motif of Pry1, and possibly of other CAP family members, is crucial for selective lipid binding and that lipid binding may occur through displacement of the loop containing this motif.
Rabih Darwiche - One of the best experts on this subject based on the ideXlab platform.
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Localization and functional characterization of the pathogenesis-related Proteins Rbe1p and Rbt4p in Candida albicans
2018Co-Authors: Yannick Bantel, Rabih Darwiche, Roger Schneiter, Steffen Rupp, Kai SohnAbstract:Members of the Cysteine-rich secretory Protein, Antigen 5 and Pathogenesis-related 1 (CAP) Protein superfamily are important virulence factors in fungi but remain poorly characterized on molecular level. Here, we investigate the cellular localization and molecular function of Rbe1p and Rbt4p, two CAP family members from the human pathogen Candida albicans. We unexpectedly found that Rbe1p localizes to budding sites of yeast cells in a disulfide bond-dependent manner. Furthermore, we show that Rbe1p and Rbt4p bind free cholesterol in vitro and export cholesteryl acetate in vivo. These findings suggest a previously undescribed role for Rbe1p in cell wall-associated processes and a possible connection between the virulence attributes of fungal CAP Proteins and sterol binding.
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the pathogen related yeast Protein pry1 a member of the CAP Protein superfamily is a fatty acid binding Protein
Journal of Biological Chemistry, 2017Co-Authors: Rabih Darwiche, Laurent Menesaffrane, David Gfeller, Oluwatoyin A Asojo, Roger SchneiterAbstract:Members of the CAP superfamily (cysteine-rich secretory Proteins, antigen 5, and pathogenesis-related 1 Proteins), also known as SCP superfamily (sperm-coating Proteins), have been implicated in many physiological processes, including immune defenses, venom toxicity, and sperm maturation. Their mode of action, however, remains poorly understood. Three Proteins of the CAP superfamily, Pry1, -2, and -3 (pathogen related in yeast), are encoded in the Saccharomyces cerevisiae genome. We have shown previously that Pry1 binds cholesterol in vitro and that Pry function is required for sterol secretion in yeast cells, indicating that members of this superfamily may generally bind sterols or related small hydrophobic compounds. On the other hand, tablysin-15, a CAP Protein from the horsefly Tabanus yao, has been shown to bind leukotrienes and free fatty acids in vitro Therefore, here we assessed whether the yeast Pry1 Protein binds fatty acids. Computational modeling and site-directed mutagenesis indicated that the mode of fatty acid binding is conserved between tablysin-15 and Pry1. Pry1 bound fatty acids with micromolar affinity in vitro, and its function was essential for fatty acid export in cells lacking the acyl-CoA synthetases Faa1 and Faa4. Fatty acid binding of Pry1 is independent of its CAPacity to bind sterols, and the two sterol- and fatty acid-binding sites are nonoverlapping. These results indicate that some CAP family members, such as Pry1, can bind different lipids, particularly sterols and fatty acids, at distinct binding sites, suggesting that the CAP domain may serve as a stable, secreted Protein domain that can accommodate multiple ligand-binding sites.
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the caveolin binding motif of the pathogen related yeast Protein pry1 a member of the CAP Protein superfamily is required for in vivo export of cholesteryl acetate
Journal of Lipid Research, 2014Co-Authors: Vineet Choudhary, Rabih Darwiche, David Gfeller, Vincent Zoete, Olivier Michielin, Roger SchneiterAbstract:Proteins belonging to the CAP superfamily are present in all kingdoms of life and have been implicated in different physiological processes. Their molecular mode of action, however, is poorly understood. Saccharomyces cerevisiae expresses three members of this superfamily, pathogen-related yeast (Pry)1, -2, and -3. We have recently shown that Pry function is required for the secretion of cholesteryl acetate and that Pry Proteins bind cholesterol and cholesteryl acetate, suggesting that CAP superfamily members may generally act to bind sterols or related small hydrophobic compounds. Here, we analyzed the mode of sterol binding by Pry1. Computational modeling indicates that ligand binding could occur through displacement of a relatively poorly conserved flexible loop, which in some CAP family members displays homology to the caveolin-binding motif. Point mutations within this motif abrogated export of cholesteryl acetate but did not affect binding of cholesterol. Mutations of residues located outside the caveolin-binding motif, or mutations in highly conserved putative catalytic residues had no effect on export of cholesteryl acetate or on lipid binding. These results indicate that the caveolin-binding motif of Pry1, and possibly of other CAP family members, is crucial for selective lipid binding and that lipid binding may occur through displacement of the loop containing this motif.
Andreas Hofmann - One of the best experts on this subject based on the ideXlab platform.
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CAP Protein superfamily members in Toxocara canis
Parasites & Vectors, 2016Co-Authors: Andreas Stroehlein, Neil D. Young, Abdul Jabbar, Pasi K. Korhonen, Ross S. Hall, Paul W. Sternberg, Andreas Hofmann, Robin B. GasserAbstract:Background Proteins of the cysteine-rich secretory Proteins, antigen 5 and pathogenesis-related 1 (CAP) superfamily are recognized or proposed to play roles in parasite development and reproduction, and in modulating host immune attack and infection processes. However, little is known about these Proteins for most parasites. Results In the present study, we explored CAP Proteins of Toxocara canis , a socioeconomically important zoonotic roundworm. To do this, we mined and curated transcriptomic and genomic data, predicted and curated full-length Protein sequences ( n = 28), conducted analyses of these data and studied the transcription of respective genes in different developmental stages of T. canis . In addition, based on information available for Caenorhabditis elegans , we inferred that selected genes (including lon-1, vap-1 , vap-2 , scl-1, scl-8 and scl-11 orthologs) of T. canis and their interaction partners likely play central roles in this parasite’s development and/or reproduction via TGF-beta and/or insulin-like signaling pathways, or via host interactions. Conclusion In conclusion, this study could provide a foundation to guide future studies of CAP Proteins of T. canis and related parasites, and might assist in finding new interventions against diseases caused by these parasites.
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Additional file 1: Table S1. of CAP Protein superfamily members in Toxocara canis
2016Co-Authors: Andreas Stroehlein, Abdul Jabbar, Andreas Hofmann, Neil Young, Ross Hall, Pasi Korhonen, Paul Sternberg, Robin GasserAbstract:CAP Protein-encoding genes of Toxocara canis. For each predicted Protein, the genomic scaffolds to which they map, including the length of the inferred amino acid sequences and InterProScan matches (including domains, motifs and signal peptides), are shown. Table S2. Pairwise comparisons of 28 predicted Toxocara canis CAP Protein sequences with homologs in Caenorhabditis elegans and parasitic nematodes including Ascaris lumbricoides (Al), Anisakis simplex (As), Ascaris suum (Asu), Brugia malayi (Bm), Caenorhabditis japonica (Cj), Caenorhabditis sinica (Cs), Dirofilaria immitis (Di), Dracunculus medinensis (Dm), Elaeophora elaphi (Ee), Enterobius vermicularis (Ev), Loa loa (Ll), Litomosoides sigmodontis (Ls), Oesophagostomum dentatum (Od), Onchocerca ochengi (Oo), Onchocerca volvulus (Ov), Parascaris equorum (Pe), Panagrellus redivivus (Pr), Steinernema carpoCAPsae (Sc), Steinernema feltiae (Sf), Steinernema glaseri (Sg), Syphacia muris (Sm), Steinernema monticolum (Smo), Steinernema sCAPterisci (Ss) and Thelazia callipaeda (Tc), with gene identification (ID) and identity (%) indicated in brackets. Table S3. Toxocara canis CAP genes (Tc-CAP) differentially transcribed (upregulated; log2-fold change: > 2) in individual life stages/sexes/tissues (pairwise comparisons). Table S4. Transcription of Toxocara canis CAP genes (Tc-CAP) in different life stages/sexes/tissues. Values are transcripts per million (TPM). (XLSX 44Â kb
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The barber's pole worm CAP Protein superfamily--A basis for fundamental discovery and biotechnology advances.
Biotechnology advances, 2015Co-Authors: Namitha Mohandas, Neil D. Young, Abdul Jabbar, Pasi K. Korhonen, Anson V. Koehler, Parisa Amani, Ross S. Hall, Paul W. Sternberg, Aaron R. Jex, Andreas HofmannAbstract:Parasitic worm Proteins that belong to the cysteine-rich secretory Proteins, antigen 5 and pathogenesis-related 1 (CAP) superfamily are proposed to play key roles in the infection process and the modulation of immune responses in host animals. However, there is limited information on these Proteins for most socio-economically important worms. Here, we review the CAP Protein superfamily of Haemonchus contortus (barber's pole worm), a highly significant parasitic roundworm (order Strongylida) of small ruminants. To do this, we mined genome and transcriptomic datasets, predicted and curated full-length amino acid sequences (n = 45), undertook systematic phylogenetic analyses of these data and investigated transcription throughout the life cycle of H. contortus. We inferred functions for selected Caenorhabditis elegans orthologs (including vap-1, vap-2, scl-5 and lon-1) based on genetic networking and by integrating data and published information, and were able to infer that a subset of orthologs and their interaction partners play pivotal roles in growth and development via the insulin-like and/or the TGF-beta signalling pathways. The identification of the important and conserved growth regulator LON-1 led us to appraise the three-dimensional structure of this CAP Protein by comparative modelling. This model revealed the presence of different topological moieties on the canonical fold of the CAP domain, which coincide with an overall charge separation as indicated by the electrostatic surface potential map. These observations suggest the existence of separate sites for effector binding and receptor interactions, and thus support the proposal that these worm molecules act in similar ways as venoms act as ligands for chemokine receptors or G Protein-coupled receptor effectors. In conclusion, this review should guide future molecular studies of these molecules, and could support the development of novel interventions against haemonchosis.