Microbial production of nicotinic acid riboside

A genetically modified bacterium capable of producing nicotinic acid riboside (NaR), wherein the bacterium comprises at least one modification selected from a group consisting of:

• a) blocking or reducing the activity of a protein which functions to repress NAD+ biosynthesis by repressing transcription of nadA, nadB, nadC genes or combinations thereof;
• b) adding or increasing the transcription of a gene which encodes L-aspartate oxidase, quinolate synthase, quinolate phoshoribosyltransferase, or combinations thereof;
• and
• c) blocking or reducing the activity of a protein which functions as a nicotinic acid mononucleotide adenyltransferase;
• wherein the bacterium with said at least one modification produces an increased amount of NaR than the bacterium without any of said modifications;
• and
• further comprising one or more additional modifications selected from the group consisting of:
• d) blocking or reducing the activity of a protein which functions as a nicotinic acid riboside phosphorylase;
• e) blocking or reducing the activity of a protein which functions as a nicotinic acid riboside kinase;
• f) blocking or reducing the activity of a protein which functions as a nicotinic acid riboside transport protein;
• g) blocking or reducing the activity of a protein which functions as a nicotinic acid phosphoribosyl transferase;
• h) adding or increasing the activity of a protein which functions as a nicotinamide mononucleotide amidohydrolase;
• and
• i) adding or increasing the activity of a protein which functions as a nicotinic acid mononucleotide hydrolase.

A method for producing NaR, comprising:

• culturing a bacterium cell under conditions effective to produce NaR and recovering NaR from the medium and thereby producing NaR, wherein the host microorganism comprises at least one modification selected from the group consisting of:
• a) blocking or reducing the activity of a protein which functions to repress NAD+ biosynthesis by repressing transcription of nadA, nadB, nadC genes or combinations thereof;
• b) adding or increasing the transcription of a gene which encodes L-aspartate oxidase, quinolate synthase, quinolate phosphoribosyltransferase, or combinations thereof;
• and
• c) blocking or reducing the activity of a protein which functions as a nicotinic acid mononucleotide adenyltransferase.