Selenocompound metabolism in bacteria involves the utilization and processing of selenium-containing compounds, which are crucial for synthesizing selenoproteins and selenoenzymes. Selenium is typically incorporated into biomolecules as selenocysteine, the 21st amino acid, through a highly specific and conserved biosynthetic pathway. The process begins with the activation of selenide to selenophosphate by the enzyme selenophosphate synthetase, providing a selenium donor for subsequent steps. Selenocysteine is then synthesized on its unique tRNA (tRNA^[Sec]) and incorporated into selenoproteins during translation at UGA codons, reprogrammed as selenocysteine codons. These selenoproteins, such as formate dehydrogenases and thioredoxin reductases, play critical roles in bacterial redox regulation and energy metabolism. Additionally, some bacteria can metabolize organic selenocompounds like selenomethionine or detoxify toxic selenium species like selenite and selenate through reduction or methylation, converting them into less harmful forms. This metabolic versatility allows bacteria to adapt to selenium-rich or selenium-deficient environments, while also contributing to global selenium cycling.

Selenocompound metabolism References