General Biological Role of Selenium

The toxicity of selenium (Se) belies the fact that it is a required trace-nutrient for many biological organisms. The general order of toxicity for the most 

Reviews of the extensive biochemistry of selenium in bacteria are available 108,109 ug fenler for Disease Control summaries for Se toxicology are also available110 A more recent review of the processes of biomethylation of selenium and tellurium in microorganisms and plants is also available.111 

As early as 1916 selenite was used to enrich and select for Typhus bacillus, quickly excluding other microorganisms. Even today, the American Public Health Association describes use of selenite for enrichment for Salmonella ssp. °° Initially an element thought to only be toxic and possibly carcinogenic, the biochemical and nutritional importance of Se in mammalian and bacterial enzyme systems has been established over the past 50 years and due in no small part to work by Stadtman and coworkers. While the minimum 

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