sp|Q8RC58|PUR7_CALS4 Phosphoribosylaminoimidazole-succinocarboxamide synthase OS=Caldanaerobacter subterraneus subsp. tengcongensis (strain DSM 15242 / JCM 11007 / NBRC 100824 / MB4) OX=273068 GN=purC PE=3 SV=2