Ricin is a highly toxic plant protein containing two peptide chains. Mainly found in castor seeds. Toxins can easily damage liver, kidney and other organs, causing bleeding, degeneration and necrosis. It can agglutinate and dissolve red blood cells, inhibit the paralysis of cardiovascular and respiratory centers, and is one of the main causes of death.

The LD50 of mice was 2.7μg/kg by intravenous injection and 7 ~10 μ g/kg by intraperitoneal injection. The LD50 value for dogs is 0.6 μ g/kg; The lethal dose to humans is about 7mg. Ricin can be used as a toxin warfare weapon for international spy intelligence personnel and terrorists to carry out insidious and destructive activities in addition to poisoning water and food through the digestive tract.

Extended data:

Toxin consists of two polypeptide chains, A and B, which are connected by a disulfide bond. At present, the amino acid sequence and secondary structure of chain A and chain B are basically clear. The toxin B chain contains two binding sites of galactose or galactose residues, which can bind to the receptor containing galactose residues on the cell surface and enter the cytoplasm through invagination to play a toxic role. Ricin A and B chains also contain 1 and two sugar branches respectively, with mannose residues at the ends of the chains, which can bind to reticuloendothelial cells, especially macrophages. The cell surface of the latter is rich in mannose receptors, which can preferentially ingest ricin, which plays an important role in the biological function of the toxin.

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