Mitochondrial phosphoenolpyruvate carboxykinase that catalyzes the conversion of oxaloacetate (OAA) to phosphoenolpyruvate (PEP), the rate-limiting step in the metabolic pathway that produces glucose from lactate and other precursors derived from the citric acid cycle (PubMed:28955899). Can play an active role in glyceroneogenesis and gluconeogenesis (PubMed:28955899). Also acts as a serine/threonine- protein kinase: phosphorylates and activates ACSL4, thereby promoting ferroptosis (PubMed:38720107). {ECO:0000269|PubMed:28955899, ECO:0000269|PubMed:38720107}. This is the function of ENSG00000100889 (PCK2, phosphoenolpyruvate carboxykinase 2, mitochondrial).