Difference between revisions of "Ricin"
(Nitpicking definitions, methinks. The molecule itself is IC, which implies ID.) |
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== Irreducible Complexity == | == Irreducible Complexity == | ||
| − | Note from the above how the molecule is formed from two separate protein chains, each from different genes in the plant genome. Without the B chain, the A chain is useless as it only acts intracellularly and has no other method of being injected into the target cell. Without the A chain, the B chain is useless as invagination of the protein into the target cell with no associated payload serves no function, and so this mutation would have died out were evolution in effect. It is implausible that both genes (plus presumably a third gene encoding for a protein to link the two chains) evolved either separately or simultaneously and therefore the molecule is an excellent example of [[Intelligent Design]]. | + | Note from the above how the molecule is formed from two separate protein chains, each from different genes in the plant genome. Without the B chain, the A chain is useless as it only acts intracellularly and has no other method of being injected into the target cell. Without the A chain, the B chain is useless as invagination of the protein into the target cell with no associated payload serves no function, and so this mutation would have died out were evolution in effect. It is implausible that both genes (plus presumably a third gene encoding for a protein to link the two chains) evolved either separately or simultaneously and therefore the molecule is an excellent example of an irreducibly complex structure, requiring [[Intelligent Design]]. |
== See also == | == See also == | ||
Revision as of 18:44, January 13, 2010
Ricin is an extremely toxic chemical produced by the seeds (or beans) of the "castor oil" plant (Ricinus communis). It achieved notoriety when it was used by the Bulgarian secret police to assassinate the BBC journalist Georgi Markov on Waterloo Bridge in 1978[1].
Method of Action
Ricin is made up of two polypeptide chains, A and B, linked by a disulfide bridge. The B chain attaches itself to a glycoprotein on the target cell and causes the molecule to be invaginated into the cell inside a vacuole. Once inside the cell the change in environment causes the disulfide bridge to break, and the B chain then forms a pore in the vacuole allowing the A chain to escape into the cell. The A chain then inhibits protein synthesis and eventually causes cell death[2].
Irreducible Complexity
Note from the above how the molecule is formed from two separate protein chains, each from different genes in the plant genome. Without the B chain, the A chain is useless as it only acts intracellularly and has no other method of being injected into the target cell. Without the A chain, the B chain is useless as invagination of the protein into the target cell with no associated payload serves no function, and so this mutation would have died out were evolution in effect. It is implausible that both genes (plus presumably a third gene encoding for a protein to link the two chains) evolved either separately or simultaneously and therefore the molecule is an excellent example of an irreducibly complex structure, requiring Intelligent Design.
See also
References
- ↑ BBC News: Flashback: Dissident's poisoning
- ↑ "Introduction to Toxicology" 2nd edition - J.A.Timbrell