Catalyzes the cleavage of 5-oxo-L-proline to form L-glutamate coupled to the hydrolysis of ATP to ADP and inorganic phosphate. Acts in the glutathione degradation pathway. 5-oxo-L-proline + ATP + 2 H2O = ADP + H(+) + L-glutamate + phosphate Expressed in roots, stems, leaves, flowers and siliques. No morphological phenotype, but high accumulation of 5-oxoproline and decreased concentration of glutamate. Belongs to the oxoprolinase family.