Pyruvate dehydrogenase arsenic inhibition

Trivalent inorganic arsenicals, such as arsenite, readily react with sulfhydryl groups, such as GSH and cysteine (Scott et al, 1993 Delnomdedieu et al, 1994). The complex between arsenic and the vicinal sulfhydryl group is particularly strong. Arsenite inhibits pyruvate dehydrogenase (PDH) activity (Hu et al, 1998), perhaps by binding to the... 

Petrick, J.S., Jagadish, B., Mash, E.A., Aposhian, H.V. (2001). Monomethyl arsenous acid (MMAIII) and arsenite LD50 in hamsters and in vitro inhibition of pyruvate dehydrogenase. Chem. Res. Toxicol. 14 651-6. 

Lewisite shares many biochemical mechanisms of injury with the other arsenical compounds. It inhibits many enzymes in particular, those with thiol groups, such as pyruvic oxidase, alcohol dehydrogenase, succinic oxidase, hexokinase, and succinic dehydrogenase (Figure 7-13). As is true with mustard, the exact mechanism by which Lewisite damages cells has not been completely defined. Inactivation of carbohydrate metabolism, primarily because of inhibition of the pyruvate dehydrogenase complex, is thought to be a key factor.98... 

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