SERAC1 and Encephalopathy: Evidence that PG, like CL, undergoes physiologically important remodeling was recently provided by the identification of serine active site containing 1 (SERAC1) mutations that cause autosomal-recessive MEGDEL syndrome [3-MGA, sensorineural deafness, encephalopathy, and neuroradiological evidence of progressive Leigh-like syndrome (Wortmann et al., 2006, 2012)].