Phoratoxin, a Toxic Protein from the Mistletoe Phoradendron tomentosum subsp. macrophyllum (Loranthaceae). Improvements in the Isolation Procedure and Further Studies on the Properties
Autor: | S. Tore Mellstrand, Gunnar Samuelsson |
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Rok vydání: | 1973 |
Předmět: |
Electrophoresis
Phoradendron tomentosum Phenylalanine Acetates Biochemistry Lethal Dose 50 Mice Valine Animals Proline Amino Acids Plant Proteins Toxins Biological Alanine Autoanalysis Plants Medicinal Chromatography biology Chemistry Tryptophan Chromatography Ion Exchange biology.organism_classification Amides Mistletoe Molecular Weight Chromatography Gel Electrophoresis Polyacrylamide Gel Leucine Isoleucine Ultracentrifugation |
Zdroj: | European Journal of Biochemistry. 32:143-147 |
ISSN: | 1432-1033 0014-2956 |
DOI: | 10.1111/j.1432-1033.1973.tb02590.x |
Popis: | In a simplified procedure for isolation of phoratoxin, the dried plant material (stems and leaves) was extracted with 2% aqueous acetic acid. The extract was treated with polyamide to remove colored impurities and subjected to gel filtration on Sephadex G-25. The high-molecular-weight fraction was chromatographed on SE-Sephadex, using a gradient elution technique, whereby pure phoratoxin was obtained. The material was homogeneous by standard criteria of protein purity. The molecular weight, determined in the ultracentrifuge by the sedimentation equilibrium method, is 5000. Phoratoxin has the following amino acid composition (residues/mole): alanine 2, arginine 3, aspartic acid 4, 1/2-cystine 6, glycine 6, histidine 1, Isoleucine 3, leucine 1, lysine 4, phenylalanine 1, proline 2, serine 5, threonine 5, tryptophan 1, tyrosine 1, valine 1. The molecular weight, calculated from the amino acid composition, is 4884. The material contains no reducing sugars, amino sugars or sialic acids. The LD50, determined by intraperitoneal injection in mice, is 0.57 ± 0.05 mg/kg bodyweight. |
Databáze: | OpenAIRE |
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