title: Isolation and characterization of a novel L-glutamate oxidase with strict substrate specificity from Streptomyces diastatochromogenes.
abstract: OBJECTIVE
  To find an L-glutamate oxidase (LGox), to be used for the quantitative analysis of L-glutamic acid, an lgox gene encoding LGox from Streptomyces diastatochromogenes was isolated, cloned and characterized.
  
  
  RESULTS
  The gene had an ORF of 1974 bp encoding a protein of 657 amino acid residues. In comparison to the LGox precursor, the proteinase K-treated enzyme exhibited improved affinity to substrate and with a Kmof 0.15 mM and Vmaxof 62 μmol min-1mg-1. The 50% thermal inactivation temperature of the proteinase K treated enzyme was increased from 50 to 70 °C. The enzyme exhibited strict specificity for L-glutamate.
  
  
  CONCLUSIONS
  LGox treated by proteinase K exhibited strict specificity for L-glutamate, good thermostability and high substrate affinity.
authors.affiliation: Shanghai Key Laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, 2901 Beidi Rd, Shanghai, China.
authors.forename: Lijuan
authors.initials: L
authors.lastname: Wang
authors.affiliation: Shanghai Key Laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, 2901 Beidi Rd, Shanghai, China.
authors.forename: Rihe
authors.initials: R
authors.lastname: Peng
authors.affiliation: Shanghai Key Laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, 2901 Beidi Rd, Shanghai, China.
authors.forename: Yongsheng
authors.initials: Y
authors.lastname: Tian
authors.affiliation: Shanghai Key Laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, 2901 Beidi Rd, Shanghai, China.
authors.forename: Man
authors.initials: M
authors.lastname: Liu
authors.affiliation: Shanghai Key Laboratory of Agricultural Genetics and Breeding, Biotechnology Research Institute of Shanghai Academy of Agricultural Sciences, 2901 Beidi Rd, Shanghai, China. jocelynwong1987@hotmail.com.|College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China. jocelynwong1987@hotmail.com.
authors.forename: Quanhong
authors.initials: Q
authors.lastname: Yao
mesh_terms: D000594:Amino Acid Oxidoreductases / Q000737:chemistry* / Q000235:genetics; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics; D003001:Cloning, Molecular; D004795:Enzyme Stability; D018698:Glutamic Acid / Q000737:chemistry; D012988:Soil Microbiology; D013302:Streptomyces / Q000201:enzymology* / Q000235:genetics; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D018698:Glutamic Acid; D000594:Amino Acid Oxidoreductases; C023061:L-glutamate oxidase
keywords: Genome walking; L-glutamate oxidase; Proteinase K; Streptomyces diastatochromogenes; lgox gene