Ricin is a typical A-B toxin consisting of a single enzymatic A subunit (RTA) and a binding B subunit (RTB) joined by a single disulfide bond. RTA possesses an RNA N-glycosidase activity; it cleaves ribosomal RNA leading to the inhibition of protein synthesis.

Ricin (/ ˈ r aɪ s ɪ n / RY-sin) is a lectin (a carbohydrate-binding protein) and a highly potent toxin produced in the seeds of the castor oil plant, Ricinus communis. The median lethal dose (LD 50 ) of ricin for mice is around 22 micrograms per kilogram of body weight via intraperitoneal injection.

2019年6月6日 · Ricin A-chain is one of the first examples of a toxin coupled to monoclonal antibodies against cell surface proteins and is used experimentally for the treatment of various cancers. This article discusses the structure of ricin, the mechanism of its synthesis and describes the biological activity of this protein.

2017年4月15日 · Protein target information for Ricin (castor bean). Find diseases associated with this biological target and compounds tested against it in bioassay experiments.

Ricin is a heterodimeric protein produced in the seeds of the castor oil plant (Ricinus communis). It is exquisitely potent to mammalian cells, being able to fatally disrupt protein synthesis by attacking the Achilles heel of the ribosome.

Ricin is a plant carbohydrate-binding protein (lectin) found in high concentration in castor beans. It is also cytotoxic, with a typical human lethal dose of approximately 5 μg/kg (135). While much less toxic than botulinum toxin or SEB, ricin can be prepared in liquid or crystalline form in large quantities from castor beans with minimal ...

Ricin is an abundant protein component of Ricinus communis seeds (castor beans) that is exquisitely toxic to mammalian cells. It consists of an enzymic polypeptide that catalyzes the N-glycosidic cleavage of a specific adenine residue from 28S ribosomal RNA, joined by a single disulfide bond to a ga …

Ricin uses an effective strategy shared by many bacterial and plant toxins, as described in the previous Molecule of the Month on cholera toxin. It is composed of two chains, as shown here from PDB entry 2aai , each with a specific job. The "B" chain (in blue) is the targeting mechanism, and the "A" chain (in red) is the toxic portion.

2004年1月1日 · Ricin is a lectin produced by the seeds of the Ricinus communis plant. It is potently toxic to mammalian cells, where it acts to inhibit the essential process of protein synthesis. Structurally, ricin is a heterodimer comprised of an enzymatic polypeptide (the A...

Ricin possesses RNA N-glycosidase activity enabling the toxin to eliminate a single adenine base from the sarcin-ricin RNA loop (SRL), which is a highly conserved structure present on the large ribosomal subunit in all species from the three domains of life.