TRANSFERASE, NP_142035.1, A PUTATIVE ACETYLTRANSFERASE, STRUCTURAL GENOMICS, JOINT CENTER FOR STRUCTURAL GENOMICS, JCSG, PROTEIN STRUCTURE INITIATIVE, PSI-2, ACETYLTRANSFERASE (GNAT) FAMILY 3DDD CRYSTAL STRUCTURE OF A PUTATIVE ACETYLTRANSFERASE (NP_142035.1) FROM PYROCOCCUS HORIKOSHII AT 2.25 A RESOLUTION