Se-methyl selenomethionine

Plants absorb Se from soil primarily as selenate and translocate it to the chloroplast, where it follows the sulfur assimilation pathway. Se is reduced (enzymatically and non-enzymatically) to selenide, which reacts with serine to form selenocysteine (76). It can be further metabolized to selenomethionine (79) and methylated to form products such as. Se-methyl selenomethionine (89). Alternatively, selenocysteine-specific methyl transferase may form -methyl selenocysteine (83), allowing the plant to accumulate extraordinarily large amounts of Se. 

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