HYDROLASE, NUDIX PROTEIN, DIADENOSINE POLYPHOSPHATE, AP4A, STRUCTURAL GENOMICS, NPPSFA, NATIONAL PROJECT ON PROTEIN STRUCTURAL AND FUNCTIONAL ANALYSES, RIKEN STRUCTURAL GENOMICS/PROTEOMICS INITIATIVE, RSGI 3I7V CRYSTAL STRUCTURE OF AP4A HYDROLASE COMPLEXED WITH AP4A (ATP) (AQ_158) FROM AQUIFEX AEOLICUS VF5