Abnormal circulating selenium concentration 2018-05-19T15:19:13Z Selenium (Se) is an essential micronutrient that exists in the form of selenocysteine (Sec), the 21st amino acid, upon its incorporation into selenoproteins via the tRNA[Sec] encoded by Trsp. Dietary intake of the micronutrient selenium is essential for normal immune functions. Selenium is cotranslationally incorporated as the 21st amino acid, selenocysteine, into selenoproteins that function to modulate pathways involved in inflammation. Any deviation from the normal circulating concentration of selenium. Abnormal serum selenium concentration Abnormal circulating organic compound concentration