A method of demethylizing an opioid to a nor-opioid is provided. The method comprises contacting an opioid with at least one enzyme. Contacting the opioid with the at least one enzyme converts the opioid to a nor-opioid. A method of converting a nor-opioid to a nal-opioid is provided. The method comprises contacting a nor-opioid with at least one enzyme. Contacting the nor-opioid with the at least one enzyme converts the nor-opioid to a nal-opioid.

Provided herein are biocatalysts and systems thereof for pterin-dependent enzymes and pathways and methods of making and using the same.

A genetic construct comprises a promoter operably linked to a first coding sequence, which encodes tyrosine hydroxylase (TH), and a second coding sequence, which encodes GTP cyclohydrolase 1 (GCH1), wherein the second coding sequence is 3 to the first coding sequence, and the first and second coding sequences are part of a single operon. The genetic construct does not encode aromatic amino acid decarboxylase (AADC).

The invention relates to expression vectors, and pharmaceutical compositions, and kits comprising the vectors, and, in particular, their use in methods for treating Parkinson's disease (PD), DOPA responsive dystonia, vascular parkinsonism, side effects associated with L-DOPA treatment for Parkinson's disease, L-DOPA induced dyskinesia, Segawa syndrome, or genetic dopamine receptor abnormalities.

A genetic construct comprises a promoter operably linked to a first coding sequence, which encodes tyrosine hydroxylase (TH), and a second coding sequence, which encodes GTP cyclohydrolase 1 (GCH1), wherein the second coding sequence is 3 to the first coding sequence, and the first and second coding sequences are part of a single operon. The genetic construct does not encode aromatic amino acid decarboxylase (AADC).

A gene sequence construct used for the treatment of central nervous system diseases: by means of the construction of an auto-processing expression vector, tyrosine hydroxylase (TH), GTP-cyclohydrolase I (GCH1), aromatic amino acid dopa decarboxylase (AADC), and so on may be simultaneously expressed; proteins are connected by means of an auto-processing unit (APU); the use of a viral vector to introduce the construct into a target cell may ultimately result in the high-efficiency expression of tyrosine hydroxylase (TH), GTP-cyclohydrolase I (GCH1), aromatic amino acid dopa decarboxylase (AADC), and so on having independent functions, being used in the prevention or treatment of Parkinson's disease, Alzheimer's disease and other neurodegenerative diseases.