Preliminary crystallographic studies of citrate synthase from an Antarctic psychrotolerant bacterium

Recombinant citrate synthase from a psychrotolerant bacterium, DS2-3R, recently isolated in Antarctica, has been crystallized. The crystals belong to space group P6(1)22 or P6(5)22, with cell dimensions a = b = 70.8, c = 307.8 Angstrom. Diffraction data collected on a synchrotron from a cryoprotected crystal extend to at least 2.0 Angstrom. Knowledge of the structure of this enzyme Rill add to the understanding of told activity and thermolability and will be of biotechnological interest. Previously, the structure of citrate synthase from Archaea inhabiting environments at 328 and 373 K, has been reported. This present study will extend our understanding of the structural integrity and activity of proteins at the temperature extremes of life.</p

Preliminary crystallographic studies of citrate synthase from an Antarctic psychrotolerant bacterium

Recombinant citrate synthase from a psychrotolerant bacterium, DS2-3R, recently isolated in Antarctica, has been crystallized. The crystals belong to space group P6(1)22 or P6(5)22, with cell dimensions a = b = 70.8, c = 307.8 Angstrom. Diffraction data collected on a synchrotron from a cryoprotected crystal extend to at least 2.0 Angstrom. Knowledge of the structure of this enzyme Rill add to the understanding of told activity and thermolability and will be of biotechnological interest. Previously, the structure of citrate synthase from Archaea inhabiting environments at 328 and 373 K, has been reported. This present study will extend our understanding of the structural integrity and activity of proteins at the temperature extremes of life.</p

Preliminary crystallographic studies of an extremely thermostable KDG aldolase from Sulfolobus solfataricus

Crystals have been grown of 2-keto-3-deoxygluconate aldolase (KDG aldolase) from the hyperthermophilic archaeon Sulfolobus solfataricus that diffract to 2.2 Angstrom resolution. The enzyme catalyses the reversible aldol cleavage of 2-keto-3-dexoygluconate to pyruvate and glyceraldehyde, the third step of a modified non-phosphorylated Entner-Doudoroff pathway of glucose oxidation. S. solfataricus grows optimally at 353 K and the enzyme itself has a half-life of 2.5 h at 373 K. Knowledge of the crystal structure of KDG aldolase will further understanding of the basis of protein hyperthermostability and create a target for site-directed mutagenesis of active-site residues, with the aim of altering substrate specificity. Three crystal forms have been obtained: orthorhombic crystals of space group P2(1)2(1)2(1), which diffract to beyond 2.15 Angstrom, monoclinic crystals of space group C2, which diffract to 2.2 Angstrom, and cubic crystals of space group P4(2)32, which diffract to 3.4 Angstrom.</p