Glucose metabolism of Treponema bryantii, an anaerobic rumen spirochete

The pathway of glucose metabolism by Treponema bryantii, an obligately anaerobic spirochete isolated from bovine rumen contents, was studied. Washed cell suspensions of the spirochete consumed glucose and CO2 and produced equimolar amounts of acetate, formate, and succinate. Carbon dioxide was essential for glucose metabolism. Determination of radioactivity in products formed from 14C-labelled glucose and NaH14CO3 and assays of enzyme activities in cell-free extracts were used to determine the pathway of glucose metabolism. Treponema bryantii catabolized glucose to pyruvate via the Embden–Meyerhof–Parnas pathway. The spirochete used a coliform pyruvate–formate lyase to degrade pyruvate and produce formate and acetate. Succinate was formed by a pathway which involved the condensation of CO2 with pyruvate (or phospho(enol)pyruvate) formed from the breakdown of glucose.