title: Cloning, purification and evaluation of the enzymatic properties of a novel arylacetonitrilase from Luminiphilus syltensis NOR5-1B: a potential biocatalyst for the synthesis of mandelic acid and its derivatives.
abstract: OBJECTIVE
  To examine nitrilase-mediated hydrolysis of nitriles to produce optically pure α-hydroxycarboxylic acids.
  
  
  RESULTS
  A novel nitrilase, GPnor51, from Luminiphilus syltensis NOR5-1B was discovered by genomic data mining. It could hydrolyze racemic o-chloromandelonitrile to (R)-o-chloromandelic acid with high enantioselectivity (ee 98.2 %). GPnor51 was overexpressed in Escherichia coli BL21 (DE3), purified, and its catalytic properties studied. GPnor51 had a broad substrate acceptance toward various nitriles with structure diversity. It was an arylacetonitrilase that uses arylacetonitriles as optimal substrates. The V max and K m of GPnor51 towards o-chloromandelonitrile were 1.9 μmol min(-1) mg(-1) protein and 0.38 mM, respectively. GPnor51 also demonstrated high enantioselectivity toward mandelonitrile and other substituted mandelonitrile.
  
  
  CONCLUSIONS
  This enzyme has a great potential for commercial production of optically pure (R)-mandelic acid and its derivatives.
authors: State Key Laboratory of Bioreactor Engineering, New World Institute of Biotechnology, East China University of Science and Technology, Shanghai, 200237, People's Republic of China.
authors: Huihui
authors: H
authors: Sun
authors: Wenyuan
authors: W
authors: Gao
authors: Haiyang
authors: H
authors: Fan
authors: Hualei
authors: H
authors: Wang
authors: Dongzhi
authors: D
authors: Wei
mesh_terms: D000619:Aminohydrolases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D003001:Cloning, Molecular; D019295:Computational Biology; D057225:Data Mining; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D020563:Gammaproteobacteria / Q000201:enzymology* / Q000235:genetics; D016680:Genome, Bacterial; D007700:Kinetics; D008333:Mandelic Acids / Q000378:metabolism*; D009570:Nitriles / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D008333:Mandelic Acids; D009570:Nitriles; D011994:Recombinant Proteins; D000619:Aminohydrolases; C021867:nitrilase; C037938:mandelic acid