The invention provides a composition for use as a medicament, comprising cells of a recombinant microorganism capable of producing increased amounts of one or more of 5-hydroxytryptophan (5-HTP), 5-hydroxytryptamine (5-HT) and tryptamine (TRM) as compared to the non-recombinant microorganism from which it was derived. The composition finds use in preventing and/or treating TRM-; 5-HTP-, or 5-HT-related disorders of the central nerve system (CNS); enteric nervous system (ENS); gastro intestine (GI) and metabolism in a mammal, and may be orally administered to a mammal in need thereof. Additionally, a composition comprising cells of a recombinant microorganism capable of producing melatonin is provided for use as a medicament, such as for treatment of depression, dementia, cancer and sleep disorder.

Methods for evolving cells or strains towards improved methyltransferase activity, particularly SAM-dependent methyltransferase activity, as well as to cells and strains useful in such methods and methods of using the evolved cells in the production of methylated products.

Methods for evolving cells or strains towards improved methyltransferase activity, particularly SAM-dependent methyltransferase activity, as well as to cells and strains useful in such methods and methods of using the evolved cells in the production of methylated products.

Described herein are variants of acetylserotonin O-methyltransferase (ASMT) as well as vectors and recombinant microbial host cells expressing such ASMT variant and their use in producing melatonin and related compounds. Preferred ASMT variants provide for a higher turnover of N-acetylserotonin into melatonin.

Provided are non-naturally occurring nucleic acids comprising a sequence encoding an enzyme or regulatory protein in tryptamine metabolism. Also provided are a recombinant microorganisms expressing the enzyme or regulatory protein. Methods of expressing the enzyme or regulatory protein are additionally provided.

Described herein are variants of acetylserotonin O-methyltransferase (ASMT) as well as vectors and recombinant microbial host cells expressing such ASMT variant and their use in producing melatonin and related compounds. Preferred ASMT variants provide for a higher turnover of N-acetylserotonin into melatonin.

Described herein are variants of acetylserotonin O-methyltransferase (ASMT) as well as vectors and recombinant microbial host cells expressing such ASMT variant and their use in producing melatonin and related compounds. Preferred ASMT variants provide for a higher turnover of N-acetylserotonin into melatonin.

Disclosed herein are enzymatic and modified host cell methods for prepared modified indole alkaloids. Also disclosed herein are modified indole alkaloids and their therapeutic use for treating diseases and disorders.

Provided herein are compositions and methods for stabilizing enzymes. Also provided are systems, compositions and methods for using the stabilized enzymes to produce a desired compound.

Methods for evolving cells or strains towards improved methyltransferase activity, particularly SAM-dependent methyltransferase activity, as well as to cells and strains useful in such methods and methods of using the evolved cells in the production of methylated products.