RIBOSOMAL PROTEIN, CBIX, SAD PHASING, STRUCTURAL GENOMICS, CHELATASE SUPER-FAMILY FOLD, 4FE-4S IRON-SULPHUR CLUSTER THE CRYSTAL STRUCTURE OF DR2241 FROM DEINOCOCCUS RADIODURANS AT 1.9 A RESOLUTION REVEALS A MULTI-DOMAIN PROTEIN WITH STRUCTURAL SIMILARITY TO CHELATASES BUT ALSO WITH TWO ADDITIONAL NOVEL DOMAINS 2JH3