CRYSTAL STRUCTURE OF COBALAMIN BIOSYNTHESIS PRECORRIN 8W DECARBOXYLASE (CBIT) TRANSFERASE, ALPHA AND BETA PROTEIN (A/B) CLASS, METHYLTRANSFERASE SUPERFAMILY, STRUCTURAL GENOMICS, NPPSFA, NATIONAL PROJECT ON PROTEIN STRUCTURAL AND FUNCTIONAL ANALYSES, RIKEN STRUCTURAL GENOMICS/PROTEOMICS INITIATIVE, RSGI 2YXD