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Table 3 Substrate specificity and chemoselectivity of purified nitrilase isolated from A. niger K10 (Nit-ANigWT) and heterologously expressed nitrilase (Nit-ANigRec)

From: Heterologous expression, purification and characterization of nitrilase from Aspergillus nigerK10

Substrate Relative activity, % Amide, molar % of total product
  Nit-ANigWT Nit-ANigRec Nit-ANigWT Nit-ANigRec
Benzonitrile 27 4.9 9 0
2-Chlorobenzonitrile 0 0 - -
3-Chlorobenzonitrile 10 3.7 3 5
4-Chlorobenzonitrile 8.4 0.2 80 0
2-Cyanopyridine 2.4 100 88 23
3-Cyanopyridine 4.6 12.9 6 2
4-Cyanopyridine 100 0.8 36 0
Phenylacetonitrile 4.9 0.2 0 0
2-Phenylpropionitrile traces 0 0 0
  1. Enzyme activity was assayed as described in Methods. The specific activities of Nit-ANigWT and Nit-ANigRec for their best substrates 4-cyanopyridine (306 U mg-1 at 45°C) and 2-cyanopyridine (9.0 U mg-1 at 38°C), respectively, were taken as 100%. Data represent the mean of four independent measurements with relative standard deviation values <5%.