The protein here named gelonin was extracted from the seeds of Gelonium multiflorum by a buffered phosphate solution and purified in a single step by chromatography on a carboxymethyl cellulose column. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate and gel filtration on Sephacryl 300 superfine showed that gelonin consists of one polypeptide chain with a molecular w...

Ribosome-inactivating proteins are a group of closely related proteins that are widely distributed throughout the plant kingdom and which share the unusual property of being able to inactivate mammalian ribosomes by an enzymic (non-stoichiometric) mechanism (1). Two major classes of these proteins are found in plants. The first contains the plant toxins (ricin, abrin, modeccin) in which an enzy...

Hartmut Franz Advances in Lectin Research Springer, Berlin 1988 188 pp.; DM 94.-ISBN 3-540-17972-0 This very instructive volume consists of four chapters, the first presenting an introduction on history. A hundred years ago, ricin was identified. In 1891, Paul Ehrlich published results of experiments on ricin and abrin. The second section deals with the preparation of plant lectins, offering al...

Two new coupling agents were synthesized for making immunotoxins containing disulfide bonds with improved stability in vivo: sodium S-4-succinimidyloxycarbonyl-alpha-methyl benzyl thiosulfate (SMBT) and 4-succinimidyloxycarbonyl-alpha-methyl-alpha(2-pyridyldithio)tolue ne (SMPT). Both reagents generate the same hindered disulfide linkage in which a methyl group and a benzene ring are attached t...

The relative expression patterns of maize (Zea mays L.) ribosome-inactivating protein 1 (RIP1)/type 3 ribosome-inactivating protein transcript were analyzed using reverse transcription and polymerase chain reaction (RT-PCR) with template materials collected separately from mature and immature root, leaf and seed tissues. The presence of RIP transcript was only detected in mature seed and immatu...

Ribosome-inactivating proteins (RIPs) were first isolated over a century ago and have been shown to be catalytic toxins that irreversibly inactivate protein synthesis. Elucidation of atomic structures and molecular mechanism has revealed these proteins to be a diverse group subdivided into two classes. RIPs have been shown to exhibit RNA N-glycosidase activity and depurinate the 28S rRNA of the...

Lectins are cell-binding and agglutinating (glyco)proteins found in a variety of living forms. They will be defined here as homogeneous carbohydrate-binding (glyco)proteins principally of plant (seed) origin but also occurring in invertebrate (and vertebrate?) forms. In recent years, lectins have been employed in studying a wide range of biological phenomena including cell differentiation and m...