title: Crystallization and preliminary X-ray diffraction studies on recombinant diaminopropionate ammonia lyase from Escherichia coli.
abstract: Diaminopropionate (DAP) ammonia lyase (a PLP-dependent enzyme; EC 4.3.1.15) catalyzes the alpha,beta-elimination reaction of both L- and D-alpha,beta-diaminopropionate to form pyruvate and ammonia. Escherichia coli DAP ammonia lyase gene was cloned and overexpressed in E. coli and the protein was purified to homogeneity and crystallized using the hanging-drop vapour-diffusion technique. Crystals of two different morphologies were obtained, one of which belonged to the tetragonal space group P4(1)2(1)2 (or P4(3)2(1)2), with unit-cell parameters a = b = 86.01, c = 209.56 A, and the other to the monoclinic space group P2(1), with unit-cell parameters a = 87.78, b = 94.35, c = 96.02 A, beta = 109.73 degrees. The tetragonal crystals diffracted X-rays to 3.0 A resolution, while diffraction from the monoclinic form extended to 2.5 A. Complete X-ray diffraction data sets have been collected for both crystal forms.
authors.affiliation: Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560012, India.
authors.forename: Venkatesan
authors.initials: V
authors.lastname: Rajaram
authors.forename: Jagannathan
authors.initials: J
authors.lastname: Rajaganapathi
authors.forename: Farida
authors.initials: F
authors.lastname: Khan
authors.forename: Handanahal S
authors.initials: HS
authors.lastname: Savithri
authors.forename: Mathur R N
authors.initials: MR
authors.lastname: Murthy
mesh_terms: D000642:Ammonia-Lyases / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D003001:Cloning, Molecular / Q000379:methods; D003460:Crystallization / Q000379:methods*; D029968:Escherichia coli Proteins / Q000737:chemistry*; D011994:Recombinant Proteins; D014961:X-Ray Diffraction
chemical_list: D029968:Escherichia coli Proteins; D011994:Recombinant Proteins; D000642:Ammonia-Lyases; C023147:diaminopropionate ammonia-lyase