title: [Expression, purification, and crystallization of a novel galactose mutarotase from Thermoanaerobacter tengcongensis].
abstract: OBJECTIVE
  To purify a novel galactose mutarotase (TTE1925) from Thermoanaerobacter tengcongensis for crystallization and X-ray diffraction.
  
  
  METHODS
  The tte 1925 gene was subcloned into the prokaryotic expression vector pGEX-6P-1 and overexpression was obtained in the E.coli BL21 (DE3) through transformation of the right recombinant plasmid that had been verified by colony PCR and sequencing. Soluble fusion protein with glutathione S-transferase tag expressed highly by the induction of isopropyl beta-D-thiogalactoside and was purified in a three-step procedure, which included Glutathione Sepharose 4B affinity, ion chromatography (Resource Q 6 mL), and gel filtration chromatography (10/300 superdex 200).
  
  
  RESULTS
  The purity of the purified protein was over 99% and a large amount of claval crystals whose X-ray diffraction reached 1.9 A were obtained.
  
  
  CONCLUSIONS
  We successfully prepared TTE1925 with high purity and obtained crystals for X-ray diffraction. These work paved the way for the further research on the 3-D structure of TTE1925 and its biological mechanism.
authors.affiliation: National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Beijing 100005, China.
authors.forename: Lan
authors.initials: L
authors.lastname: Wu
authors.forename: Zhong
authors.initials: Z
authors.lastname: Qian
authors.forename: Jun
authors.initials: J
authors.lastname: Fu
authors.forename: Shi-ying
authors.initials: SY
authors.lastname: Miao
authors.forename: Lin-fang
authors.initials: LF
authors.lastname: Wang
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000302:isolation & purification*; D002238:Carbohydrate Epimerases / Q000096:biosynthesis / Q000737:chemistry / Q000302:isolation & purification*; D003001:Cloning, Molecular; D003460:Crystallization; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005822:Genetic Vectors; D046968:Thermoanaerobacter / Q000201:enzymology* / Q000235:genetics; D014169:Transformation, Bacterial
chemical_list: D001426:Bacterial Proteins; D002238:Carbohydrate Epimerases; C459183:galactose mutarotase