title: [Heterologous expression and characterization of L200F/D215K mutant of homoserine dehydrogenase from Corynebacterium pekinense AS1.299].
abstract: OBJECTIVE
  To obtain a new homoserine dehydrogenase with better properties from Corynebacterium pekinense by the spatial structure transfromation.
  
  
  METHODS
  Double mutants L200F/D215A, L200F/D215E, L200F/D215G and L200F/D215K were constructed by site-directed mutagenesis and expressed in E. coli BL21. L200F/D215K was characterized for its highest catalytic efficiency and compared with that of L200F.
  
  
  RESULTS
  The Vmax of L200F/D215K was 36.92 U/mg, 1.24 times as that of L200F. The optimum reaction temperature of L200F/D215K was 37 degrees C, 2 degrees C higher than that of L200F. The optimum pH of L200F/D215K was 7.5, the same as that of L200F. The half-life time of L200F/D215K under optimum temperature was 4.16 h and was 1.12 times as that of L200F. Both L200F/D215K and L200F had good resistance to organic solvents and metal ions.
  
  
  CONCLUSIONS
  Through the spatial structure transformation, the enzymatic activity was increased, and the enzymology properties was optimized.
authors: Shuxia
authors: S
authors: Shen
authors: Yunming
authors: Y
authors: Zhu
authors: Li
authors: L
authors: Fang
authors: Jinkun
authors: J
authors: Xu
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D003352:Corynebacterium / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics; D004795:Enzyme Stability; D006715:Homoserine Dehydrogenase / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D006715:Homoserine Dehydrogenase