regulate the “on” and “off” states of pyruvate formate lyase to regulate anaerobic glucose metabolism: pyruvate formate lyase activase (AE) and pyruvate formate lyase deactivase. Activated pyruvate formate lyase allows formation of acetyl-CoA, a small molecule important in the production of energy, when pyruvate is available. Deactivated pyruvate formate lyase, even with substrates present, does not catalyze the reaction. Pyruvate formate lyase activase is part of the radical SAM (S-adenosylmethionine) superfamily. The enzyme turns pyruvate formate lyase “on” by converting Gly734 (G-H) into a Gly734 radical (G*) via a 5'-deoxyadenosyl radical (via a radical SAM). For more information about radical SAM activation and radical SAM enzymes, see the discussion by Wang et al., 2007. Pyruvate formate lyase deactivase turns pyruvate formate lyase “off” by quenching the Gly734 radical. Furthermore, pyruvate formate lyase is sensitive to molecular oxygen (O2), the presence of which shuts the enzyme off. References EC 2.3.1 Enzymes of known structure