Abrus precatorius Abrine

Abrus Agglutinin Abrus precatorius (abrin, jequirity Gal, GalNAc... 

Agarose. — Agarose has been used without modification as an affinity chromatographic support for the separation of Abrin A and Abrin B, anti-tumour proteins from Abrus precatorius. Abrin A binds to the support and is eluted with D-galactose but Abrin B does not bind. 

Ricin a toxalbumin phytotoxin from Ricinus seeds. M, 66,000,493 amino acid residues. R. inhibits protein biosynthesis (causes dissociation of polysomes) and has antitumor properties. It consists of an A-chain (M, 32,000) and a B-chain (M, 34,000) joined by disulfide bridges. After reductive separation by 2-mercap-toethanol, both chains show increased inhibitor activity but markedly decreased toxicity. Toxic activity is carried by the A-chain (effectomer), while the B-chain (haptomer) binds the toxin to the cell surface. Similar action and structure are possessed by abrin (M, 65,000 A-chain 30,000, B-chain 35,000), a toxalbumin from the red seeds of Abrus precatorius. Abrin is used in opthalmology. 

Abrus precatorius L. Siang Si Zi (Prayer beads) (seed) 1-Abrine, precatorine, hypaphorine, cycloarternol, squalene, trigonelline, 5-P-cholanic acid.33-450 Antiemetic, expectorant, parasiticide. 

Abrus precatorius L. China L-abrine, precatorine, squalene, hypaphorine, trigonelline, cycloarterenol, 5- 3-cholanic acid.33 Antiemetic, an expectorant, parasiticide. 

Similar toxic RIPs are found in other plants. Examples are trichosanthin, a type I toxin from the root tubers of Trichosanthes kirilowii (Cucurbitaceae), abrin, a type II toxin from the small brightly coloured red and black jequirity seeds (Abrus precatorius Leguminosae/Fabaceae), and viscumin, a type II toxin from the leaf and stems of mistletoe (Viscum album, Loranthaceae). 

Abrin, from jequirity beans (Abrus precatorius), resembles ricin so closely in its action that the difference was established only when it was noted that immunity against one did not constitute immunity against the other. 

Abrine (I), the A7tl-methyl derivative of L-tryptophan, occurs in the seeds of the jequirity (Abrus precatorius L.) (12, 13) so far it has not... 

Abrus Abrin-a Abrus precatorius (Fabaceae) toxic A RAG (rat rRNA A4324 in R/S... 

Abrus Abrins (toxic lectins) Abrus precatorius, A. pulchellus Apoptotic (Gal-specific lectin)... 

Abrin is a plant source Type 2 RIP. It is found in Abrus precatorius (rosary pea, Indian licorice, jequirity bean). The toxicology of abrin is considered to be very similar to ricin. A similar Abrus toxin is pulchellin, produced by A. pul-chellus (Millard and LeClaire, 2008). The rosary pea has been reported to be more toxic than castor beans (Griffiths et al, 1994). Species sensitivity is variable and horses are considered to be the most sensitive. The mature goat is considered to be a more resistant species and 2 g of seed/kg body weight is reported as a lethal dose. The lethal dose for cattle is reported at 600 mg of seed/kg body weight. It is likely that abrin is denatured in the rumen (Burrows and Tyrl, 2001). 

In the early 20th Century, abrin was used for homicide in several countries, including India and Sri Lanka (Hart, 1963 Byam and Archibald, 1921). The seeds of Abrus precatorius were ground, mixed to a paste with water and then formed into needles known as suis . When the needles had hardened, they were used to pierce the skin of the victim. In at least one documented case, this resulted in death. The patient was pricked in the cheek by a needle, which he extracted immediately he died two days later. No clinical details were provided (Byam and Archibald, 1921). 

Toxins derived from plants are generally very easy to produce in large quantities at minimal cost in a low-technology environment. Ricin, a protein derived from the bean of the castor plant, and abrin, a very similar toxin from Abrus precatorius are typical plant toxins. 

In the late 1800s, Stillmark4 discovered that the beans of the castor plant contained a toxic protein, which he named ricin. He discovered that ricin caused agglutination of erythrocytes and precipitation of serum proteins. (The lectin properties of ricin and abrin [a closely related toxin from the bean of Abrus precatorius] and their use as tools for research were described in 1972 by Sharon and Lis.5)... 

Jeguirity bean Abrus precatorius 1 Toxalbumin (abrin) severe fatal gastroenteritis reported... 

Abrin, crystalline Abrus precatorius seeds (jequirity beans)... 

Two anti-tumour proteins, abrin A and abrin B, have been isolated from Abrus precatorius by ion-exchange and affinity chromatographic methods. Both proteins have similar molecular weights (6.5 X10 ), exist as dimers, and have similar, but not identical, amino-acid compositions. 4-Labelled abrin A and abrin B bind to Sarcoma 180 cells, but the patterns of inhibition of binding by different sugars are different. 

Abrin, a potent toxin, is extracted from the seeds of the rosary pea (Abrus precatorius). Due to its easy availability and preparation, this toxin is an attractive option for weap-onizing in poor countries, and thus has also been included in the Sch ule 1 of the CWC. The mechanism of action of abrin is very similar to that of ricin however, in mice, abrin is 75 times more toxic than that of ricin (0.04 pg/ kg for abrin is equivalent to 3pg/kg of ricin). Similar to ricin, inhalation of abrin is found to be more toxic than ingestion. However, abrin ingestion has reported to be toxic to the liver, unlike ricin. At the cellular level, abrin is a potent toxalbumin known to cause cell death by inhibiting protein synthesis (namely, type 2 ribosomal inhibitory protein). Further, abrin is also known to induce endothelial cell damage leading to an increase in cell permeability, fluid and protein leakage, and tissue edema. 

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