1wmb
From Proteopedia
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| , resolution 2.0Å | |||||||
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| Ligands: | , | ||||||
| Activity: | 3-hydroxybutyrate dehydrogenase, with EC number 1.1.1.30 | ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Crystal structure of NAD dependent D-3-hydroxybutylate dehydrogenase
Overview
The gene coding for d-3-hydroxybutyrate dehydrogenase (HBDH) was cloned from Pseudomonas fragi. The nucleotide sequence contained a 780 bp open reading frame encoding a 260 amino acid residue protein. The recombinant enzyme was efficiently expressed in Escherichia coli cells harboring pHBDH11 and was purified to homogeneity as judged by SDS-PAGE. The enzyme showed a strict stereospecificity to the D-enantiomer (3R-configuration) of 3-hydroxybutyrate as a substrate. Crystals of the ligand-free HBDH and of the enzyme-NAD+ complex were obtained using the hanging-drop, vapor-diffusion method. The crystal structure of the HBDH was solved by the multiwavelength anomalous diffraction method using the SeMet-substituted enzyme and was refined to 2.0 A resolution. The overall structure of P.fragi HBDH, including the catalytic tetrad of Asn114, Ser142, Tyr155, and Lys159, shows obvious relationships with other members of the short-chain dehydrogenase/reductase (SDR) family. A cacodylate anion was observed in both the ligand-free enzyme and the enzyme-NAD+ complex, and was located near the catalytic tetrad. It was shown that the cacodylate inhibited the NAD+-dependent D-3-hydroxybutyrate dehydrogenation competitively, with a Ki value of 5.6 mM. From the interactions between cacodylate and the enzyme, it is predicted that substrate specificity is achieved through the recognition of the 3-methyl and carboxyl groups of the substrate.
About this Structure
1WMB is a Single protein structure of sequence from Pseudomonas fragi. Full crystallographic information is available from OCA.
Reference
D-3-hydroxybutyrate dehydrogenase from Pseudomonas fragi: molecular cloning of the enzyme gene and crystal structure of the enzyme., Ito K, Nakajima Y, Ichihara E, Ogawa K, Katayama N, Nakashima K, Yoshimoto T, J Mol Biol. 2006 Jan 27;355(4):722-33. Epub 2005 Nov 14. PMID:16325199
Page seeded by OCA on Mon Mar 31 00:38:10 2008
