An archaeal nitrile hydratase from the halophilic archaeon A07HB70 exhibits high tolerance to 3-cyanopyridine and nicotinamide

Nitrile hydratase (NHase, EC 4.2.1.84) is widely used in the industrial production of biosynthetic amide compounds. NHases obtained from prokaryotic and eukaryotic sources have been widely studied, while the NHases derived from archaeal sources have not been reported. Here, we focused on a distinctive NHase derived from a halophilic archaeon (archaeon A07HB70, A.r NHase) that thrives in high-salt environments. A notable feature of this enzyme is the natural fusion of the alpha subunit with the activator. A.r NHase retained 89.14 % of its activity after exposure to 4.0 M substrate and 97.52 % of its activity after exposure to 4.0 M product. These findings indicate that A.r NHase exhibits significantly higher tolerance to both substrate and product compared to NHases derived from other sources, which may be due to its unique genetic structure. The investigation of such highly stable archaeal NHase can offer a theoretical foundation for modifying NHase derived from other sources. This, in turn, would enhance the potential industrial application of NHase.

Automated summary

This study focused on a halophilic archaeal nitrile hydratase (NHase) and found that it exhibited higher tolerance to substrates and products compared to NHases from other sources. The unique genetic structure of this highly stable archaeal NHase could provide a theoretical foundation for modifying and enhancing the industrial application of NHase.