Te(IV), selenite, and selenomethionine toxicity and bioaccumulation. Homozygous diploid gene knockout mutants with confirmed significant deviations in Te(IV) phenotypes were pinned onto solid agar medium containing 0.2 or 0.8 mM Na2SeO3 or 0.03 or 0.06 mM selenomethionine (SeMet) and evaluated manually after 1, 2, 3, and 6 days of growth on solid agar medium.