A lack of negative feedback on which enzyme can result in the accumulation of 5-oxoproline in the setting of APAP depletion of glutathione stores?
gamma glutamylcysteine synthestase
Armenian, Patil, et al. “5-Oxoprolinemia Causing Elevated Anion Gap Metabolic Acidosis in the Setting of Acetaminophen Use.” The Journal of Emergency Medicine, vol. 43, no. 1, 2012, pp. 54–57., doi:10.1016/j.jemermed.2011.06.017.