Crystallization and preliminary X-ray characterization of arylamine N-acetyltransferase C (BanatC) from Bacillus anthracis.

The arylamine N-acetyltransferase (NAT) enzymes are xenobiotic metabolizing enzymes that have been found in a large range of eukaryotes and prokaryotes. These enzymes catalyse the acetylation of arylamine drugs and/or pollutants. Recently, a Bacillus anthracis NAT isoform (BanatC) has been cloned and shown to acetylate the sulfonamide antimicrobial sulfamethoxazole (SMX). Subsequently, it was shown that BanatC contributes to the resistance of this bacterium to SMX. Here, the crystallization and the X-ray characterization of BanatC (Y38F mutant) are reported. The crystals belong to the tetragonal space group P4(1)2(1)2 or P4(3)2(1)2, with unit-cell parameters a = b = 53.70, c = 172.40 A, and diffract to 1.95 A resolution on a synchrotron source.