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Yeldur P Venkatesh - One of the best experts on this subject based on the ideXlab platform.
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identification and characterization of a basic thaumatin like protein tlp 2 as an allergen in Sapodilla plum manilkara zapota
Molecular Nutrition & Food Research, 2014Co-Authors: Venkatesh L Hegde, Hassan Ashok G Kumar, Kundimi Sreenath, Muralidhar L Hegde, Yeldur P VenkateshAbstract:Scope: Cases of oral allergy syndrome following the ingestion of Sapodilla plum (Manilkara zapota) have been reported rarely. As the causative allergens are not known, the main objective of this study was to identify and characterize the important allergens in Sapodilla. Methods and results: Allergy to Sapodilla was diagnosed by case history, skin prick test, and serum allergen–specific IgE. The allergen was detected by IgE immunoblotting, purified on SP–Sepharose and characterized by native/SDS–PAGE, IEF, MS, and amino acid composition. Several cases of allergy to Sapodilla fruit were identified; majority of the Sapodilla-allergic subjects (6/7) experienced typical oral allergy syndrome symptoms, and allergen–specific IgE to the purified protein was positive. The allergen has a pI ≥9.5 and high contents of arginine, threonine, glycine, and cysteine. Circular dichroism revealed a secondary structure rich in beta sheets/turns. Based on its N-terminal sequence of A-T-F-D-I-Q-N-N-C-X-Y-, the allergen (21 578 Da) was identified as a thaumatin-like protein by homology. Conclusion: The causative allergen in Sapodilla plum has been identified and characterized as a highly basic thaumatin-like protein belonging to the pathogenesis-related protein (PR–5) family, which has been recognized as a new family of conserved, cross-reactive plant allergens.
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in silico analyses of structural and allergenicity features of Sapodilla manilkara zapota acidic thaumatin like protein in comparison with allergenic plant tlps
Molecular Immunology, 2014Co-Authors: Hassan Ashok G Kumar, Yeldur P VenkateshAbstract:Thaumatin-like proteins (TLPs) belong to the pathogenesis-related family (PR-5) of plant defense proteins. TLPs from only 32 plant genera have been identified as pollen or food allergens. IgE epitopes on allergens play a central role in food allergy by initiating cross-linking of specific IgE on basophils/mast cells. A comparative analysis of pollen- and food-allergenic TLPs is lacking. The main objective of this investigation was to study the structural and allergenicity features of Sapodilla (Manilkara zapota) acidic TLP (TLP 1) by in silico methods. The allergenicity prediction of composite sequence of Sapodilla TLP 1 (NCBI B3EWX8.1, G5DC91.1) was performed using FARRP, Allermatch and Evaller web tools. A homology model of the protein was generated using banana TLP template (1Z3Q) by HHPRED-MODELLER. B-cell linear epitope prediction was performed using BCpreds and BepiPred. Sapodilla TLP 1 matched significantly with allergenic TLPs from olive, kiwi, bell pepper and banana. IgE epitope prediction as performed using AlgPred indicated the presence of 2 epitopes (epitope 1: residues 36–48; epitope 2: residues 51–63), and a comprehensive analysis of all allergenic TLPs displayed up to 3 additional epitopes on other TLPs. It can be inferred from these analyses that plant allergenic TLPs generally carry 2–3 IgE epitopes. ClustalX alignments of allergenic TLPs indicate that IgE epitopes 1 and 2 are common in food allergenic TLPs, and IgE epitopes 2 and 3 are common in pollen allergenic TLPs; IgE epitope 2 overlaps with a portion of the thaumatin family signature. The secondary structural elements of TLPs vary markedly in regions 1 and 2 which harbor all the predicted IgE epitopes in all food and pollen TLPs in either of the region. Further, based on the number of IgE epitopes, food TLPs are grouped into rosid and non-rosid clades. The number and distribution of the predicted IgE epitopes among the allergenic TLPs may explain the specificity of food or pollen allergy as well as the varied degree of cross-reactivity among plant foods and/or pollens.
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food allergy and anaphylaxis 2046 cloning and characterization of the gene for acidic thaumatin like protein an important allergen from Sapodilla plum manilkara zapota
World Allergy Organization Journal, 2013Co-Authors: Yeldur P Venkatesh, H Ashok G Kumar, Venkatesh L Hegde, S M ShettyAbstract:Methods A case of oral allergy syndrome to Sapodilla and custard apple was investigated following approval by Institutional Ethics Committee. Sapodilla allergy was confirmed by diagnostic tests (SPT and allergen-specific IgE). Sapodilla proteins were separated on SP-Sepharose by adsorption at pH 4 followed by step elution at pH 5 (SP1), and with increasing NaCl – 0.1 M (SP2) and 0.2 M (SP3). Forward primers and nested reverse primers specific to the SP1 component were designed based on its N-terminal sequence and conserved regions of homologous plant TLPs. PCR was performed using Sapodilla (cv. cricket ball) leaf genomic DNA as template.
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basic and clinical immunology 3033 structural analyses and allergencity predicition of Sapodilla manikara zapota acidic thaumatin like protein by bioinformatics
World Allergy Organization Journal, 2013Co-Authors: Yeldur P Venkatesh, H Ashok G KumarAbstract:Background Oral allergy syndrome to Sapodilla plum is caused by a 21 kD allergen existing as two isoforms: an acidic thaumatin-like protein (TLP-1) and a basic thaumatin-like protein (TLP-2). The composite sequence of TLP-1 comprising the N-terminal sequence 1-7 (A-T-F-D-V/I-V-N-) and the deduced sequence 8-207 (GenBank JN624813.1) was used for this analysis. The major objective of this study was to analyze the structural features and allergenicity prediction of TLP-1 by bioinformatics.
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characterization and gene cloning of an acidic thaumatin like protein tlp 1 an allergen from Sapodilla fruit manilkara zapota
Allergology International, 2013Co-Authors: Hassan Ashok G Kumar, Venkatesh L Hegde, S M Shetty, Yeldur P VenkateshAbstract:ABSTRACT Background Allergy to Sapodilla ( Manilkara zapota ) fruit ingestion is rare. An independent study from our group has identified a basic thaumatin-like protein (TLP 2) as the major allergen. The present study was aimed at identifying and characterizing additional allergens from Sapodilla. Methods Allergic subjects were identified by case history, skin prick test (SPT) and allergen-specific IgE. Sapodilla extract was fractionated using SP-Sepharose into 3 components (SP1, SP2 and SP3) which were analyzed by native/SDS-PAGE, IgE-immunoblot, isoelectric focusing (IEF) and N-terminal sequencing. The conserved regions of plant TLPs and the N-terminal sequence were used to design primers for PCR. Results SPT and ELlSA confirmed a subject with oral allergy syndrome (OAS) to Sapodilla and custard apple. Two proteins (26.9 and 24.5 kDa; reducing conditions) were detected as allergens, of which the latter in SP2 has already been identified as basic TLP (TLP 2). The 26.9kDa protein present in SP1 was identified as an acidic TLP based on native PAGE, IEF and N-terminal sequencing. Presence of a basic β-1,3-glucanase in SP3 was inferred by zymography. Sequence analysis of the genomic clone of the acidic TLP gene revealed that it is intronless and non-glycosylated. Evolutionary relatedness to olive, grape and kiwi fruit allergenic TLPs were inferred by phylogenetic analysis. Conclusions An acidic TLP (TLP 1) was identified as a new allergen in Sapodilla. TLP 1 is a single polypeptide (207 residues) belonging to the thaumatin family of the GH64-TLP-SF superfamily. Clinically, Sapodilla should be considered in the list of fruits causing OAS.
Philippe Nondédéo - One of the best experts on this subject based on the ideXlab platform.
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Ancient Maya sylviculture of breadnut (Brosimum alicastrum Sw.) and Sapodilla (Manilkara zapota (L.) P. Royen) at Naachtun (Guatemala): A reconstruction based on charcoal analysis
Quaternary International, 2017Co-Authors: Lydie Dussol, Michelle Elliott, Dominique Michelet, Philippe NondédéoAbstract:Abstract Researchers have long argued that the ancient Maya actively exploited forest resources, but the nature of these forest economies and their long-term impact on the landscape are still vigorously debated. We address this issue through charcoal analysis at the Classic site of Naachtun (Northern Guatemala), systematically analyzing the use of the breadnut ( Brosimum alicastrum ) and Sapodilla ( Manilkara zapota ) trees for domestic firewood over eight centuries. These two species are among the most economically and ecologically valuable for modern Maya people, and have been at the core of the debate concerning ancient Maya subsistence economy. We carry out an experimental anthracological study and discuss the implications of its results from a diachronic and taphonomic perspective for the ancient Maya site of Naachtun. We assume that Sapodilla wood was intensively exploited as a primary source of fuel throughout the site's occupation history, and that its importance in the fuel economy until the city's abandonment was the product of careful management practices. Our results also indicate that breadnut wood use may have been much more significant than generally perceived in the charcoal records of Maya Lowland sites. An increase in breadnut wood use during the Late Classic, which corresponds to the demographic apogee of Naachtun, is evidence that this tree was of sufficient economic and/or ecological importance to be maintained despite the growing population pressure on the local forest.
Venkatesh L Hegde - One of the best experts on this subject based on the ideXlab platform.
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identification and characterization of a basic thaumatin like protein tlp 2 as an allergen in Sapodilla plum manilkara zapota
Molecular Nutrition & Food Research, 2014Co-Authors: Venkatesh L Hegde, Hassan Ashok G Kumar, Kundimi Sreenath, Muralidhar L Hegde, Yeldur P VenkateshAbstract:Scope: Cases of oral allergy syndrome following the ingestion of Sapodilla plum (Manilkara zapota) have been reported rarely. As the causative allergens are not known, the main objective of this study was to identify and characterize the important allergens in Sapodilla. Methods and results: Allergy to Sapodilla was diagnosed by case history, skin prick test, and serum allergen–specific IgE. The allergen was detected by IgE immunoblotting, purified on SP–Sepharose and characterized by native/SDS–PAGE, IEF, MS, and amino acid composition. Several cases of allergy to Sapodilla fruit were identified; majority of the Sapodilla-allergic subjects (6/7) experienced typical oral allergy syndrome symptoms, and allergen–specific IgE to the purified protein was positive. The allergen has a pI ≥9.5 and high contents of arginine, threonine, glycine, and cysteine. Circular dichroism revealed a secondary structure rich in beta sheets/turns. Based on its N-terminal sequence of A-T-F-D-I-Q-N-N-C-X-Y-, the allergen (21 578 Da) was identified as a thaumatin-like protein by homology. Conclusion: The causative allergen in Sapodilla plum has been identified and characterized as a highly basic thaumatin-like protein belonging to the pathogenesis-related protein (PR–5) family, which has been recognized as a new family of conserved, cross-reactive plant allergens.
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food allergy and anaphylaxis 2046 cloning and characterization of the gene for acidic thaumatin like protein an important allergen from Sapodilla plum manilkara zapota
World Allergy Organization Journal, 2013Co-Authors: Yeldur P Venkatesh, H Ashok G Kumar, Venkatesh L Hegde, S M ShettyAbstract:Methods A case of oral allergy syndrome to Sapodilla and custard apple was investigated following approval by Institutional Ethics Committee. Sapodilla allergy was confirmed by diagnostic tests (SPT and allergen-specific IgE). Sapodilla proteins were separated on SP-Sepharose by adsorption at pH 4 followed by step elution at pH 5 (SP1), and with increasing NaCl – 0.1 M (SP2) and 0.2 M (SP3). Forward primers and nested reverse primers specific to the SP1 component were designed based on its N-terminal sequence and conserved regions of homologous plant TLPs. PCR was performed using Sapodilla (cv. cricket ball) leaf genomic DNA as template.
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characterization and gene cloning of an acidic thaumatin like protein tlp 1 an allergen from Sapodilla fruit manilkara zapota
Allergology International, 2013Co-Authors: Hassan Ashok G Kumar, Venkatesh L Hegde, S M Shetty, Yeldur P VenkateshAbstract:ABSTRACT Background Allergy to Sapodilla ( Manilkara zapota ) fruit ingestion is rare. An independent study from our group has identified a basic thaumatin-like protein (TLP 2) as the major allergen. The present study was aimed at identifying and characterizing additional allergens from Sapodilla. Methods Allergic subjects were identified by case history, skin prick test (SPT) and allergen-specific IgE. Sapodilla extract was fractionated using SP-Sepharose into 3 components (SP1, SP2 and SP3) which were analyzed by native/SDS-PAGE, IgE-immunoblot, isoelectric focusing (IEF) and N-terminal sequencing. The conserved regions of plant TLPs and the N-terminal sequence were used to design primers for PCR. Results SPT and ELlSA confirmed a subject with oral allergy syndrome (OAS) to Sapodilla and custard apple. Two proteins (26.9 and 24.5 kDa; reducing conditions) were detected as allergens, of which the latter in SP2 has already been identified as basic TLP (TLP 2). The 26.9kDa protein present in SP1 was identified as an acidic TLP based on native PAGE, IEF and N-terminal sequencing. Presence of a basic β-1,3-glucanase in SP3 was inferred by zymography. Sequence analysis of the genomic clone of the acidic TLP gene revealed that it is intronless and non-glycosylated. Evolutionary relatedness to olive, grape and kiwi fruit allergenic TLPs were inferred by phylogenetic analysis. Conclusions An acidic TLP (TLP 1) was identified as a new allergen in Sapodilla. TLP 1 is a single polypeptide (207 residues) belonging to the thaumatin family of the GH64-TLP-SF superfamily. Clinically, Sapodilla should be considered in the list of fruits causing OAS.
S M Shetty - One of the best experts on this subject based on the ideXlab platform.
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food allergy and anaphylaxis 2046 cloning and characterization of the gene for acidic thaumatin like protein an important allergen from Sapodilla plum manilkara zapota
World Allergy Organization Journal, 2013Co-Authors: Yeldur P Venkatesh, H Ashok G Kumar, Venkatesh L Hegde, S M ShettyAbstract:Methods A case of oral allergy syndrome to Sapodilla and custard apple was investigated following approval by Institutional Ethics Committee. Sapodilla allergy was confirmed by diagnostic tests (SPT and allergen-specific IgE). Sapodilla proteins were separated on SP-Sepharose by adsorption at pH 4 followed by step elution at pH 5 (SP1), and with increasing NaCl – 0.1 M (SP2) and 0.2 M (SP3). Forward primers and nested reverse primers specific to the SP1 component were designed based on its N-terminal sequence and conserved regions of homologous plant TLPs. PCR was performed using Sapodilla (cv. cricket ball) leaf genomic DNA as template.
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characterization and gene cloning of an acidic thaumatin like protein tlp 1 an allergen from Sapodilla fruit manilkara zapota
Allergology International, 2013Co-Authors: Hassan Ashok G Kumar, Venkatesh L Hegde, S M Shetty, Yeldur P VenkateshAbstract:ABSTRACT Background Allergy to Sapodilla ( Manilkara zapota ) fruit ingestion is rare. An independent study from our group has identified a basic thaumatin-like protein (TLP 2) as the major allergen. The present study was aimed at identifying and characterizing additional allergens from Sapodilla. Methods Allergic subjects were identified by case history, skin prick test (SPT) and allergen-specific IgE. Sapodilla extract was fractionated using SP-Sepharose into 3 components (SP1, SP2 and SP3) which were analyzed by native/SDS-PAGE, IgE-immunoblot, isoelectric focusing (IEF) and N-terminal sequencing. The conserved regions of plant TLPs and the N-terminal sequence were used to design primers for PCR. Results SPT and ELlSA confirmed a subject with oral allergy syndrome (OAS) to Sapodilla and custard apple. Two proteins (26.9 and 24.5 kDa; reducing conditions) were detected as allergens, of which the latter in SP2 has already been identified as basic TLP (TLP 2). The 26.9kDa protein present in SP1 was identified as an acidic TLP based on native PAGE, IEF and N-terminal sequencing. Presence of a basic β-1,3-glucanase in SP3 was inferred by zymography. Sequence analysis of the genomic clone of the acidic TLP gene revealed that it is intronless and non-glycosylated. Evolutionary relatedness to olive, grape and kiwi fruit allergenic TLPs were inferred by phylogenetic analysis. Conclusions An acidic TLP (TLP 1) was identified as a new allergen in Sapodilla. TLP 1 is a single polypeptide (207 residues) belonging to the thaumatin family of the GH64-TLP-SF superfamily. Clinically, Sapodilla should be considered in the list of fruits causing OAS.
Lydie Dussol - One of the best experts on this subject based on the ideXlab platform.
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Ancient Maya sylviculture of breadnut (Brosimum alicastrum Sw.) and Sapodilla (Manilkara zapota (L.) P. Royen) at Naachtun (Guatemala): A reconstruction based on charcoal analysis
Quaternary International, 2017Co-Authors: Lydie Dussol, Michelle Elliott, Dominique Michelet, Philippe NondédéoAbstract:Abstract Researchers have long argued that the ancient Maya actively exploited forest resources, but the nature of these forest economies and their long-term impact on the landscape are still vigorously debated. We address this issue through charcoal analysis at the Classic site of Naachtun (Northern Guatemala), systematically analyzing the use of the breadnut ( Brosimum alicastrum ) and Sapodilla ( Manilkara zapota ) trees for domestic firewood over eight centuries. These two species are among the most economically and ecologically valuable for modern Maya people, and have been at the core of the debate concerning ancient Maya subsistence economy. We carry out an experimental anthracological study and discuss the implications of its results from a diachronic and taphonomic perspective for the ancient Maya site of Naachtun. We assume that Sapodilla wood was intensively exploited as a primary source of fuel throughout the site's occupation history, and that its importance in the fuel economy until the city's abandonment was the product of careful management practices. Our results also indicate that breadnut wood use may have been much more significant than generally perceived in the charcoal records of Maya Lowland sites. An increase in breadnut wood use during the Late Classic, which corresponds to the demographic apogee of Naachtun, is evidence that this tree was of sufficient economic and/or ecological importance to be maintained despite the growing population pressure on the local forest.
