Diversity of inorganic arsenite biotransformation

Biotransformation of inorganic arsenic in mammals is catalyzed by three ser ial enzyme activities: arsenate reductase, arsenite methyltransferase, and monomethylarsonate methyltransferase. Our laboratory has purified and chara cterized these enzymes in order to understand the mechanisms and elucidate the variations of the responses to arsenate/arsenite challenge. Our results indicate a marked deficiency and diversity of these enzyme activities in v arious animal species.