Ricin A won’t kill you, but with Ricin B it does. Ricin A is present in barley. Is a person that consumes barley and has Ricin A in large quantities their blood stream more susceptible to poisoning with Castor beans. that have both Ricin A and Ricin B? I eat barley and handle castor beans and plants on occasions, so amaze yourselves this is not just hypothetical.
Do we not have anyone an expert on this? Come on you organic chemists.
Ricin is a protein synthesis inhibitor that acts to inhibit ribosome function, and are a class of proteins labeled ribosome inhibitor proteins (RIP). Ribosomes are protein structures that translate the code of messenger RNA (mRNA) to assemble the basic amino acids into peptide sequences that form other proteins. In other words, RIPs inhibit cell function by preventing them from forming the proteins needed to support intracellular function. Ricin is formed of two chains, labeled RTA and RTB. While both are capable of interfering with ribosome function inside the cell, only the RTB chain has saccharide-binding abilities that allow it to be readily uptaken into cells. Although RTA appears independently in some organisms, RTB only appears naturally with RTA.
So to answer your question, no; having RTA in your system does not make you significantly more sensitive to RTB, nor are you likely to ingest or absorb enough ricin through incidental handling to result in cytotoxicity. Although the LD50 of ricin is small, the natural vectors are highly restrictive, and its use as a weapon requires extracting and processing ricin into a highly concentrated form, and then converting it to an inhalant or injecting it into the target. Both the United States and the Soviet Union conducted research on ricin and essentially dismissed it as an effective weapon for battlefield deployment as it proved to be less lethal than existing pulmonary and nerve toxins in deployment.
Here is the CDC page on ricin. There are many other online resources on ricin that provide both practical and biochemical description of ricin.
Stranger
I didn’t know if small amounts of ricin B did something to ricin A in your body. The answer no. Thanks.