Abstract
l-Arabinonate dehydratase (EC 4.2.1.25) and d-xylonate
dehydratase (EC 4.2.1.82) are two enzymes that are
involved in a nonphosphorylative oxidation pathway of
pentose sugars. l-Arabinonate dehydratase converts
l-arabinonate into 2-dehydro-3-deoxy-l-arabinonate, and
d-xylonate dehydratase catalyzes the dehydration of
d-xylonate to 2-dehydro-3-deoxy-d-xylonate. l-Arabinonate
and d-xylonate dehydratases belong to the IlvD/EDD
family, together with 6-phosphogluconate dehydratases and
dihydroxyacid dehydratases. No crystal structure of any
l-arabinonate or d-xylonate dehydratase is available in
the PDB. In this study, recombinant l-arabinonate
dehydratase from Rhizobium leguminosarum bv. trifolii
(RlArDHT) and d-xylonate dehydratase from Caulobacter
crescentus (CcXyDHT) were heterologously expressed in
Escherichia coli and purified by the use of affinity
chromatography followed by gel-filtration chromatography.
The purified proteins were crystallized using the
hanging-drop vapour-diffusion method at 293 K. Crystals
of RlArDHT that diffracted to 2.40 Å resolution were
obtained using sodium formate as a precipitating agent.
They belonged to space group P21, with unit-cell
parameters a = 106.07, b = 208.61, c = 147.09 Å, [beta] =
90.43°. Eight RlArDHT molecules (two tetramers) in the
asymmetric unit give a V M value of 3.2 Å3 Da-1 and a
solvent content of 62%. Crystals of CcXyDHT that
diffracted to 2.66 Å resolution were obtained using
sodium formate and polyethylene glycol 3350. They
belonged to space group C2, with unit-cell parameters a =
270.42, b = 236.13, c = 65.17 Å, ß = 97.38°. Four CcXyDHT
molecules (a tetramer) in the asymmetric unit give a V M
value of 4.0 Å3 Da-1 and a solvent content of 69%.
Original language | English |
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Pages (from-to) | 604-608 |
Journal | Acta Crystallographica Section F: Structural Biology Communications |
Volume | 72 |
Issue number | Part 8 |
DOIs | |
Publication status | Published - 2016 |
MoE publication type | A1 Journal article-refereed |
Keywords
- Caulobacter crescentus
- d-xylonate dehydratase
- IlvD/EDD enzymes
- l-arabinonate dehydratase
- Rhizobium leguminosarum bv. trifolii
- [Fe-S] cluster