Fig. 3. Diagram of the γ-butyrobetaine–crotonobetaine–carnitine cycle primarily based on Elssner et al. (2001), with additions based on Bernal et al. (2008) and Canovas et al. (2003). GBB, γ-butyrobetaine; CaiA, crotonobetaine reductase; CaiB, CoA transferase; CaiC, betaine:CoA ligase; CaiD, enoyl-CoA hydratase; FixABCX, electron transfer flavoproteins. Electron movement is denoted by e− .
