Nitrile hydratase (NHase) has attracted substantial attention for industrial applications to produce largescale amides. Several NHases have been investigated for functional expression in Escherichia colt (E. coil). A Fe-type NHase was obtained from an acetamiprid-degrading bacterium, Pseudoxanthomonas sp. AAP-7 and functionally expressed in E. colt BL21 (DE3). No significant NHase activity was detected from the E. colt expressing either the NHase gene alone or NHase and P46K genes transcribed as one unit. Purified recombinant NHase, co-expressed with P46K on two separate plasmids, exhibited the maximal enzyme activity. Furthermore, a GST tag attached to the N-terminus of alpha subunit resulted in a slight increase in the solubility and stability of NHase compared with a His tag at the C-terminus of beta subunit. When co-expressed with the chaperones GroEL-GroES, the yield of the soluble recombinant NHase was improved substantially, while a small decrease in NHase activity was observed. The putative activator P46K was strictly required for production of the recombinant NHase for full enzyme activity, although the chaperones GroEL-GroES appeared to assist NHase to fold properly. This study of the expression of a fully active Fe-type NHase would provide another example to enhance our understanding of NHase biosynthesis. (C) 2017 Elsevier Ltd. All rights reserved.