Sarin

Sarin acts on the enzyme Acetylcholinesterase The banned nerve agent sarin (fig. 1) is a potent inhibitor of AChE. It is a highly volatile liquid that reacts rapidly with the active­site serine of AChE (PDB entries 2y2v and 2whp), displacing the fluorine and forming an oxygen­phosphorus bond (view­2) that cannot be hydrolysed. The catalytic serine is thus irreversibly modified and the enzyme inactivated. Sarin and similar organophosphorous nerve agents cause death by asphyxiation as acetylcholine accumulates in the neuromuscular junction and the muscles around the lungs go into spasm. Some insecticides, such as fenamiphos (e.g., PDB entries 2jgf, 2wu3, 2wu4) and malathion, are also organophosphates and act in the same way as sarin. These insecticides have varying levels of toxicity to humans; in fact, malathion is used to treat head lice! However, as is the case with sarin, exposure to sublethal doses can lead to permanent neurological problems. https://www.ebi.ac.uk/pdbe/widgets/QuipStories/AChE/AChE.pdf