title: Cloning, expression, purification, crystallization and preliminary X-ray crystallographic analyses of threonyl-tRNA synthetase editing domain from Aeropyrum pernix.
abstract: The proofreading function of aminoacyl-tRNA synthetases is crucial in maintaining the fidelity of protein synthesis. Most archaeal threonyl-tRNA synthetases (ThrRSs) possess a unique proofreading domain unrelated to their eukaryotic/bacterial counterpart. The crystal structure of this domain from the archaeon Pyrococcus abysii in complex with its cognate and noncognate substrate analogues had given insights into its catalytic and discriminatory mechanisms. To probe further into the mechanistic and evolutionary aspects of this domain, work has been extended to another archaeon Aeropyrum pernix. The organism possesses two proteins corresponding to threonyl-tRNA synthetase, i.e. ThrRS1 and ThrRS2, encoded by two different genes, thrS1 and thrS2, respectively. ThrRS1 is responsible for aminoacylation and ThrRS2 for proofreading activity. Here the purification, crystallization and preliminary X-ray crystallographic investigation of the N-terminal proofreading domain of ThrRS2 from A. pernix is reported. The crystals belong to either the P4(1)2(1)2 or P4(3)2(1)2 space group and consist of one monomer per asymmetric unit.
authors.affiliation: CSIR-Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India.
authors.forename: Sadeem
authors.initials: S
authors.lastname: Ahmad
authors.forename: Antony S K
authors.initials: AS
authors.lastname: Sravankumar
authors.forename: Shobha P
authors.initials: SP
authors.lastname: Kruparani
authors.forename: Rajan
authors.initials: R
authors.lastname: Sankaranarayanan
mesh_terms: D041522:Aeropyrum / Q000201:enzymology*; D000595:Amino Acid Sequence; D019843:Archaeal Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000302:isolation & purification; D002850:Chromatography, Gel; D002852:Chromatography, Ion Exchange; D003001:Cloning, Molecular; D003460:Crystallization; D018360:Crystallography, X-Ray; D004926:Escherichia coli; D057927:Hydrophobic and Hydrophilic Interactions; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D013914:Threonine-tRNA Ligase / Q000096:biosynthesis / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D019843:Archaeal Proteins; D013914:Threonine-tRNA Ligase