Crystallization and preliminary X-ray analysis of binary and ternary complexes of Haloferax mediterranei glucose dehydrogenase

• Published in: Acta crystallographica. Section F, Structural biology and crystallization communications Vol. 61; no. 8; pp. 743 - 746
• Main Authors: Esclapez, Julia, Britton, K. Linda, Baker, Patrick J., Fisher, Martin, Pire, Carmen, Ferrer, Juan, Bonete, María José, Rice, David W.
• Format: Journal Article
• Language: English
• Published: 5 Abbey Square, Chester, Cheshire CH1 2HU, England Munksgaard International Publishers 01.08.2005; International Union of Crystallography
• Subjects: archaea; CHAINS; CITRATES; CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CRYSTALLIZATION; Crystallization Communications; Crystallography, X-Ray; CYSTEINE; Data Collection; DIFFUSION; GLUCOSE; Glucose 1-Dehydrogenase - chemistry; Glucose 1-Dehydrogenase - metabolism; glucose dehydrogenase; Haloferax mediterranei - enzymology; HISTIDINE; MDR superfamily; MOLECULES; MONOCRYSTALS; Multiprotein Complexes - chemistry; Multiprotein Complexes - metabolism; NADP - chemistry; POTASSIUM; site-directed mutagenesis; SODIUM; SPACE GROUPS; STRUCTURAL CHEMICAL ANALYSIS; ZINC; Zinc - chemistry
• ISSN: 1744-3091; 1744-3091
• DOI: 10.1107/S1744309105019949

Haloferax mediterranei glucose dehydrogenase (EC 1.1.1.47) belongs to the medium‐chain alcohol dehydrogenase superfamily and requires zinc for catalysis. In the majority of these family members, the catalytic zinc is tetrahedrally coordinated by the side chains of a cysteine, a histidine, a cysteine or glutamate and a water molecule. In H. mediterranei glucose dehydrogenase, sequence analysis indicates that the zinc coordination is different, with the invariant cysteine replaced by an aspartate residue. In order to analyse the significance of this replacement and to contribute to an understanding of the role of the metal ion in catalysis, a range of binary and ternary complexes of the wild‐type and a D38C mutant protein have been crystallized. For most of the complexes, crystals belonging to space group I222 were obtained using sodium/potassium citrate as a precipitant. However, for the binary and non‐productive ternary complexes with NADPH/Zn, it was necessary to replace the citrate with 2‐methyl‐2,4‐pentanediol. Despite the radical change in conditions, the crystals thus formed were isomorphous.