title: Crystal structure of aspartate decarboxylase at 2.2 A resolution provides evidence for an ester in protein self-processing.
abstract: The structure of L-aspartate-alpha-decarboxylase from E. coli has been determined at 2.2 A resolution. The enzyme is a tetramer with pseudofour-fold rotational symmetry. The subunits are six-stranded beta-barrels capped by small alpha-helices at each end. The active sites are located between adjacent subunits. The electron density provides evidence for catalytic pyruvoyl groups at three active sites and an ester at the fourth. The ester is an intermediate in the autocatalytic self-processing leading to formation of the pyruvoyl group. This unprecedented structure provides novel insights into the general phenomenon of protein processing.
authors.affiliation: Department of Biochemistry, Cambridge, UK.
authors.forename: A
authors.initials: A
authors.lastname: Albert
authors.forename: V
authors.initials: V
authors.lastname: Dhanaraj
authors.forename: U
authors.initials: U
authors.lastname: Genschel
authors.forename: G
authors.initials: G
authors.lastname: Khan
authors.forename: M K
authors.initials: MK
authors.lastname: Ramjee
authors.forename: R
authors.initials: R
authors.lastname: Pulido
authors.forename: B L
authors.initials: BL
authors.lastname: Sibanda
authors.forename: F
authors.initials: F
authors.lastname: von Delft
authors.forename: M
authors.initials: M
authors.lastname: Witty
authors.forename: T L
authors.initials: TL
authors.lastname: Blundell
authors.forename: A G
authors.initials: AG
authors.lastname: Smith
authors.forename: C
authors.initials: C
authors.lastname: Abell
mesh_terms: D000595:Amino Acid Sequence; D003198:Computer Simulation; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000201:enzymology; D004952:Esters; D005583:Fourier Analysis; D005968:Glutamate Decarboxylase / Q000737:chemistry* / Q000378:metabolism*; D046911:Macromolecular Substances; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D017510:Protein Folding; D017433:Protein Structure, Secondary
chemical_list: D004952:Esters; D046911:Macromolecular Substances; C019104:aspartate-alpha-decarboxylase; D005968:Glutamate Decarboxylase