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Updated: May 7, 2026

X-Ray Crystallography to Study the Oligomeric State Transition of the Thermotoga maritima M42 Aminopeptidase TmPep1050
Published on: May 13, 2020
Crystallization and preliminary X-ray diffraction studies of D-threo-3-hydroxyaspartate dehydratase isolated from
Yu Matsumoto1, Yoshiaki Yasutake, Yuki Takeda
1Laboratory of Microbial Physiology, Research Faculty of Agriculture, Hokkaido University, Kita-9, Nishi-9, Kita-ku, Sapporo 060-8589, Japan.
Abstract:
D-threo-3-Hydroxyaspartate dehydratase (D-THA DH) isolated from the soil bacterium Delftia sp. HT23 is a novel enzyme consisting of 380 amino-acid residues which catalyzes the conversion of D-threo-3-hydroxyaspartate to oxaloacetate and ammonia. D-THA DH also catalyzes the dehydration of L-threo-3-hydroxyaspartate, L-erythro-3-hydroxyaspartate and D-serine. The amino-acid sequence of D-THA DH shows significant similarity to that of two eukaryotic D-serine dehydratases derived from Saccharomyces cerevisiae and chicken kidney. D-THA DH is classified into the fold-type III group of pyridoxal enzymes and is the first example of a fold-type III dehydratase derived from a prokaryote. Overexpression of recombinant D-THA DH was carried out using a Rhodococcus erythropolis expression system and the obtained protein was subsequently purified and crystallized. The crystals of D-THA DH belonged to space group I4₁22, with unit-cell parameters a=b=157.3, c=157.9 Å. Single-wavelength anomalous diffraction data were collected to a resolution of 2.0 Å using synchrotron radiation at the wavelength of the Br K absorption edge.
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