The Experts below are selected from a list of 210 Experts worldwide ranked by ideXlab platform
Toshiaki Osawa - One of the best experts on this subject based on the ideXlab platform.
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Correlation between carbohydrate‐binding specificity and amino acid sequence of carbohydrate‐binding regions of Cytisus‐type anti‐H(O) lectins
FEBS Letters, 1992Co-Authors: Yukiko Konami, Kazuo Yamamoto, Toshiaki Osawa, Tatsuro IrimuraAbstract:A carbohydrate-binding peptide of the di-N-acetylchitoblose-binding Cytisus sessilifolius anti-H(O) lectin I (CSA-I) was isolated from the endoproteinase Asp-N digest of CSA-I by affinity chromatography on a column of N-acetyl-d-glucosamine oligomer-Sepharose (GIcNAc oligomer-Sepharose). The amino acid sequence of the carbohydrate-binding peptide of CSA-I was determined to be DTYFGKTYNPW using a gas-phase protein sequencer. This sequence corresponds to the sequence from Asp-129 to Trp-139 based on the primary structure of CSA-I, and shows a high degree of homology to those of the putative carbohydrate-binding peptide of the Laburnum alpinum lectin I (LAA-I) (DTYFGKAYNPW) and of the Ulex europaeus lectin II (UEA-II) (DSYFGKTYNPW). The binding of these three anti-H(O) lectins is known to be inhibited by di-N-acetylchitobiose but not by l-fucose. These results strongly suggest that there is a good correlation between the carbohydrate-binding specificity and the amino acid sequence of the carbohydrate-binding regions of di-N-acetylchitobiose-binding lectins.
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Carbohydrate-binding peptides from several anti-H(O) lectins.
Journal of Biochemistry, 1992Co-Authors: Kazuo Yamamoto, Yukiko Konami, Toshiaki Osawa, Tatsuro IrimuraAbstract:Peptide fragments have been obtained from L-fucose-binding anti-H(O) lectins [Lotus tetragonolobus lectin (LTA) and Ulex europeus lectin I (UEA-I)] and di-N-acetylchitobiose-binding anti-H(O) lectins [Ulex europeus lectin II (UEA-II) and Laburnum alpinum lectin I (LAA-I)] by treatment with endoproteinase Asp-N or Lys-C. The peptide fragments were fractionated by affinity chromatography on a column of Fuc-Gel for LTA and UEA-I, and on a column of N-acetyl-D-glucosamine oligomer-Sepharose for UEA-II and LAA-I. The peptides with affinity for these columns were identified by peptide sequencing. All of these retarded peptides were found to be parts of the metal-binding regions of these lectins. It is strongly suggested that these peptides represent the carbohydrate-binding and metal ion-binding sites of legume lectins, respectively.
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the primary structure of the Laburnum alpinum seed lectin
FEBS Letters, 1991Co-Authors: Yukiko Konami, Kazuo Yamamoto, Satoshi Toyoshima, Toshiaki OsawaAbstract:The complete amino acid sequence of the Laburnum alpinum di-N-acetylchitobiose-binding lectin was determined by using a protein sequencer after digestion with endoproteinases Lys-C and Asp-N, and compared with those of other leguminous plant lectins.
F C Czygan - One of the best experts on this subject based on the ideXlab platform.
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uber die alkaloidzusammensetzung der oberirdischen teile von Laburnum watereri kirchn dipp
Biochemie und Physiologie der Pflanzen, 1990Co-Authors: Roland Greinwald, Wulf Schultze, F C CzyganAbstract:Summary The alkaloid composition of the overground parts (leaves, petioles, stems, flowers, fruits and seeds) of Laburnum watereri (hybrid of Laburnum alpinum × L. anagyroides ) and its seasonal changes (from march to november) have been studied by different chromatographic (TLC, capillary GC) and spectroscopic (GC/MS, HRMS, 1 H-NMR, 13 C-NMR, IR, UV) methods. Seeds only contain cytisine. Besides cytisine, traces of methylcytisine and ammodendrine 12 further alkaloids could be identified in the fruits, among which β-isosparteine, 14e-hydroxysparteine and epi-baptifoline have been found for the first time in the genus Laburnum . Following the seasonal changes of the alkaloid composition of the fruits, an increase of epibaptifoline and ammodendrine was established during ripening, while the content of the main compound cytisine strongly declined. The highest total amount of alkaloids (with 80 to 90% cytisine) was found in the buds in the spring. During the further development of the leaves, the cystine content decreases and a methylation of this alkaloid begins. In summer the alkaloid concentration reaches the lowest level. In the course of July epi-baptifoline (erroneously reported as methylcytisine in literature) increases and becomes the main alkaloid for the following 6 months.
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cytisine 12 carboxy ethylester a quinolizidine alkaloid from Laburnum watereri and its occurrence in the leguminosae
Phytochemistry, 1990Co-Authors: R Greinwald, Peter Bachmann, Ludger Witte, F C CzyganAbstract:Abstract A new lupin alkaloid, cytisine-12-carboxy-ethylester, was isolated from suspension cultures of Laburnum watereri. Its structure was determined by spectroscopic data and by direct comparison with a synthetic sample. The distribution of the new alkaloid amongst different genera of the Leguminosae is reported.
Yukiko Konami - One of the best experts on this subject based on the ideXlab platform.
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Correlation between carbohydrate‐binding specificity and amino acid sequence of carbohydrate‐binding regions of Cytisus‐type anti‐H(O) lectins
FEBS Letters, 1992Co-Authors: Yukiko Konami, Kazuo Yamamoto, Toshiaki Osawa, Tatsuro IrimuraAbstract:A carbohydrate-binding peptide of the di-N-acetylchitoblose-binding Cytisus sessilifolius anti-H(O) lectin I (CSA-I) was isolated from the endoproteinase Asp-N digest of CSA-I by affinity chromatography on a column of N-acetyl-d-glucosamine oligomer-Sepharose (GIcNAc oligomer-Sepharose). The amino acid sequence of the carbohydrate-binding peptide of CSA-I was determined to be DTYFGKTYNPW using a gas-phase protein sequencer. This sequence corresponds to the sequence from Asp-129 to Trp-139 based on the primary structure of CSA-I, and shows a high degree of homology to those of the putative carbohydrate-binding peptide of the Laburnum alpinum lectin I (LAA-I) (DTYFGKAYNPW) and of the Ulex europaeus lectin II (UEA-II) (DSYFGKTYNPW). The binding of these three anti-H(O) lectins is known to be inhibited by di-N-acetylchitobiose but not by l-fucose. These results strongly suggest that there is a good correlation between the carbohydrate-binding specificity and the amino acid sequence of the carbohydrate-binding regions of di-N-acetylchitobiose-binding lectins.
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Carbohydrate-binding peptides from several anti-H(O) lectins.
Journal of Biochemistry, 1992Co-Authors: Kazuo Yamamoto, Yukiko Konami, Toshiaki Osawa, Tatsuro IrimuraAbstract:Peptide fragments have been obtained from L-fucose-binding anti-H(O) lectins [Lotus tetragonolobus lectin (LTA) and Ulex europeus lectin I (UEA-I)] and di-N-acetylchitobiose-binding anti-H(O) lectins [Ulex europeus lectin II (UEA-II) and Laburnum alpinum lectin I (LAA-I)] by treatment with endoproteinase Asp-N or Lys-C. The peptide fragments were fractionated by affinity chromatography on a column of Fuc-Gel for LTA and UEA-I, and on a column of N-acetyl-D-glucosamine oligomer-Sepharose for UEA-II and LAA-I. The peptides with affinity for these columns were identified by peptide sequencing. All of these retarded peptides were found to be parts of the metal-binding regions of these lectins. It is strongly suggested that these peptides represent the carbohydrate-binding and metal ion-binding sites of legume lectins, respectively.
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the primary structure of the Laburnum alpinum seed lectin
FEBS Letters, 1991Co-Authors: Yukiko Konami, Kazuo Yamamoto, Satoshi Toyoshima, Toshiaki OsawaAbstract:The complete amino acid sequence of the Laburnum alpinum di-N-acetylchitobiose-binding lectin was determined by using a protein sequencer after digestion with endoproteinases Lys-C and Asp-N, and compared with those of other leguminous plant lectins.
K Becker - One of the best experts on this subject based on the ideXlab platform.
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studies on the antioxidant activity of indian Laburnum cassia fistula l a preliminary assessment of crude extracts from stem bark leaves flowers and fruit pulp
Food Chemistry, 2002Co-Authors: Perumal Siddhuraju, P S Mohan, K BeckerAbstract:Abstract The antioxidant properties of 90% ethanol extracts of leaves, and 90% methanol extracts of stem bark, pulp and flowers from Indian Laburnum ( Cassia fistula L.) were investigated. The antioxidant activity power was in the decreasing order of stem bark, leaves, flowers and pulp and was well correlated with the total polyphenolic content of the extracts. The reason for low antioxidant activity in the flower and pulp fractions could be the presence of some prooxidants, such as chrysophanol and reducing sugars which dominate the antioxidant compounds present in the extracts. Thus, the stem bark had more antioxidant activity in terms of reducing power, inhibition of peroxidation, O 2 −. and DPPH radical scavenging ability.
R Greinwald - One of the best experts on this subject based on the ideXlab platform.
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cytisine 12 carboxy ethylester a quinolizidine alkaloid from Laburnum watereri and its occurrence in the leguminosae
Phytochemistry, 1990Co-Authors: R Greinwald, Peter Bachmann, Ludger Witte, F C CzyganAbstract:Abstract A new lupin alkaloid, cytisine-12-carboxy-ethylester, was isolated from suspension cultures of Laburnum watereri. Its structure was determined by spectroscopic data and by direct comparison with a synthetic sample. The distribution of the new alkaloid amongst different genera of the Leguminosae is reported.
