LYASE, OROTIDINE 5'-MONOPHOSPHATE DECARBOXYLASE, H2-UMP, CRYSTAL STRUCTURE, DECARBOXYLASE, PYRIMIDINE BIOSYNTHESIS 3G1H CRYSTAL STRUCTURE OF OROTIDINE 5'-MONOPHOSPHATE DECARBOXYLASE FROM METHANOBACTERIUM THERMOAUTOTROPHICUM COMPLEXED WITH 5,6-DIHYDROURIDINE 5'-MONOPHOSPHATE