Engineered imine reductases and methods for the reductive amination of ketone and amine compounds
The present disclosure provides engineered polypeptides having imine reductase activity, polynucleotides encoding the engineered imine reductases, host cells capable of expressing the engineered imine reductases, and methods of using these engineered polypeptides with a range of ketone and amine substrate compounds to prepare secondary and tertiary amine product compounds.
1. An engineered polypeptide having imine reductase activity, wherein said polypeptide has at least 90% sequence identity to SEQ ID NO:2, and comprises a substitution at a position corresponding to position 111 of SEQ ID NO:2, wherein the amino acid at position 111 has been replaced with a non-polar, polar, or basic residue.
2. The engineered polypeptide having imine reductase activity of claim 1 , wherein said polypeptide has at least 90% sequence identity to SEQ ID NO:2, wherein the amino acid at the position corresponding to position 111 of SEQ ID NO:2 has been replaced with methionine, arginine, glutamine, or serine.
3. The engineered polypeptide of claim 1 , wherein said polypeptide is capable of converting substrate compound (1a) pyruvate,
and substrate compound (2b) butylamine
to product compound (3b), N-2-(butylamino)propanoic acid,
under suitable reaction conditions.
4. The engineered polypeptide of claim 1 , wherein said polypeptide is capable of converting substrate compound (1b) cyclohexanone,
and substrate compound (2a) L-norvaline
to product compound (3c), (S)-2-(cyclohexylamino)pentanoic acid,
under suitable reaction conditions.
5. The engineered polypeptide of claim 1 , wherein said polypeptide is capable of converting substrate compound (1b) cyclohexanone,
and substrate compound (2b) butylamine
to product compound (3d), N-butylcyclohexanamine,
under suitable reaction conditions.
6. The engineered polypeptide of claim 1 , wherein said polypeptide is capable of converting substrate compound (1i),
and substrate compound (2b)
to product compound (3n),
under suitable reaction conditions.
7. The engineered polypeptide of claim 1 , wherein said polypeptide is capable of converting substrate compound (1j),
and substrate compound (2b)
to product compound (3o),
under suitable reaction conditions.