Recombinant microorganisms, plants, and plant cells are disclosed that have been engineered to have reduced levels or activity of one or more alcohol dehydrogenases or aldehyde reductases thereby increasing the production of benzylisoquinoline alkaloids and/or benzylisoquinoline alkaloid precursors.

Recombinant microorganisms, plants, and plant cells are disclosed that have been engineered to have reduced levels or activity of one or more alcohol dehydrogenases or aldehyde reductases thereby increasing the production of benzylisoquinoline alkaloids and/or benzylisoquinoline alkaloid precursors.

Recombinant microorganisms, plants, and plant cells are disclosed that have been engineered to have reduced levels or activity of one or more alcohol dehydrogenases or aldehyde reductases thereby increasing the production of benzylisoquinoline alkaloids and/or benzylisoquinoline alkaloid precursors.

Recombinant microorganisms, plants, and plant cells are disclosed that have been engineered to have reduced levels or activity of one or more alcohol dehydrogenases or aldehyde reductases thereby increasing the production of benzylisoquinoline alkaloids and/or benzylisoquinoline alkaloid precursors.

The present invention relates to the provision of an enzymatic method for the preparation of 2,6-bis(hydroxy methyl)pyridine starting from 2,6-lutidine using a mutated xylene monooxygenase enzyme, termed ppXMO, comprising a xylM subunit and a xylA subunit from Pseudomonas putida, wherein said mutated enzymes harbor an amino acid exchange at position 116 of the amino acid sequence of XylM component. The essence of the invention is that the methionine (M) at this position is replaced with an aminoacid selected in the group consisting of asparagine (N), lysine (K), arginine (R) and glycine (G), which surprisingly results in a direct methyl hydroxylation of 6-methyl-2-pyridine methanol resulting in improved overall process yield, less side products are produced, avoidance of toxic reaction intermediates and minimizing the need for involvement of endogenous reductase enzymes as well as NADPH and its regeneration. Other enzymes related to XylM of P. putida harbouring the same amino acid exchange at the highly conserved region around position 116 or its equivalent also exhibit similar improved characteristics.