title: Structure of arylamine N-acetyltransferase from Mycobacterium tuberculosis determined by cross-seeding with the homologous protein from M. marinum: triumph over adversity.
abstract: Arylamine N-acetyltransferase from Mycobacterium tuberculosis (TBNAT) plays an important role in the intracellular survival of the microorganism inside macrophages. Medicinal chemistry efforts to optimize inhibitors of the TBNAT enzyme have been hampered by the lack of a three-dimensional structure of the enzyme. In this paper, the first structure of TBNAT, determined using a lone crystal produced using cross-seeding with the homologous protein from M. marinum, is reported. Despite the similarity between the two enzymes (74% sequence identity), they show distinct physical and biochemical characteristics. The structure elegantly reveals the characteristic features of the protein surface as well as details of the active site of TBNAT relevant to drug-discovery efforts. The crystallographic analysis of the diffraction data presented many challenges, since the crystal was twinned and the habit possessed pseudo-translational symmetry.
authors.affiliation: Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, England.
authors.forename: Areej
authors.initials: A
authors.lastname: Abuhammad
authors.forename: Edward D
authors.initials: ED
authors.lastname: Lowe
authors.forename: Michael A
authors.initials: MA
authors.lastname: McDonough
authors.forename: Patrick D
authors.initials: PD
authors.lastname: Shaw Stewart
authors.forename: Stefan A
authors.initials: SA
authors.lastname: Kolek
authors.forename: Edith
authors.initials: E
authors.lastname: Sim
authors.forename: Elspeth F
authors.initials: EF
authors.lastname: Garman
mesh_terms: D001191:Arylamine N-Acetyltransferase / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D020134:Catalytic Domain; D003460:Crystallization / Q000379:methods; D018360:Crystallography, X-Ray; D004795:Enzyme Stability; D008958:Models, Molecular; D019910:Mycobacterium marinum / Q000201:enzymology*; D009169:Mycobacterium tuberculosis / Q000201:enzymology*; D011487:Protein Conformation; D053838:Scattering, Small Angle; D017386:Sequence Homology, Amino Acid
chemical_list: D001426:Bacterial Proteins; D001191:Arylamine N-Acetyltransferase
keywords: arylamine N-acetyltransferase; cholesterol catabolism; cross-seeding; crystal microseeding; drug targets; microseed matrix screen; pseudo-translational symmetry; tuberculosis; twinning