Recombinant microorganisms, plants, and plant cells are disclosed that have been engineered to express novel recombinant genes encoding steviol biosynthetic enzymes and UDP-glycosyltransferases (UGTs). Such microorganisms, plants, or plant cells can produce steviol or steviol glycosides, e.g., rubusoside or Rebaudioside A, which can be used as natural sweeteners in food products and dietary supplements.

The present invention relates to a method for increasing the degree of glycosylation of a composition comprising steviol glycosides, which method comprises: a. contacting said composition comprising steviol glycosides with a recombinant microorganism, a cell free extract derived from such a microorganism or an enzyme preparation derived from either thereof; and b. thereby to increase the degree of glycosylation of the composition comprising steviol glycosides, wherein the recombinant microorganism comprises one or more nucleotide sequence(s) encoding: a polypeptide having ent-copalyl pyrophosphate synthase activity; a polypeptide having ent-Kaurene synthase activity; a polypeptide having ent-Kaurene oxidase activity; a polypeptide having kaurenoic acid 13-hydroxylase activity; and one or more polypeptides having UDP-glucosyltransferase activity whereby expression of the nucleotide sequence(s) confer(s) on the microorganism the ability to produce at least one steviol glycoside. The present invention also relates to a composition comprising steviol glycosides obtainable by such a method.

The present invention relates a variant polypeptide having geranylgeranyl pyrophosphate synthase activity, which variant polypeptide comprises an amino acid sequence which, when aligned with a geranylgeranyl pyrophosphate synthase comprising the sequence set out in SEQ ID NO: 1, comprises at least one substitution of an amino acid residue corresponding to any of amino acids at positions 92, 100 or 235 said positions being defined with reference to SEQ ID NO: 1 and wherein the variant has one or more modified properties as compared with a reference polypeptide having geranylgeranyl pyrophosphate synthase activity. A variant polypeptide of the invention may be used in a recombinant host for the production of steviol or a steviol glycoside.

The present invention relates to a method for the production of a diterpene or a glycosylated diterpene, which method comprises: a. fermenting a recombinant microorganism of the genus Yarrowia in a suitable fermentation medium at a temperature of about 29 C. or higher, wherein the microorganism comprises one or more nucleotide sequence(s) encoding: a polypeptide having ent-copalyl pyrophosphate synthase activity; a polypeptide having ent-Kaurene synthase activity; a polypeptide having ent-Kaurene oxidase activity; and a polypeptide having kaurenoic acid 13-hydroxylase activity and whereby expression of the nucleotide sequence(s) confer(s) on the microorganism the ability to produce at least steviol; and b. recovering the diterpene or glycosylated diterpene.

The present invention relates to a method for the production of a diterpene or a glycosylated diterpene, which method comprises: a. fermenting a recombinant microorganism of the genus Yarrowia in a suitable fermentation medium at a temperature of about 29 C. or higher, wherein the microorganism comprises one or more nucleotide sequence(s) encoding: a polypeptide having ent-copalyl pyrophosphate synthase activity; a polypeptide having ent-Kaurene synthase activity; a polypeptide having ent-Kaurene oxidase activity; and a polypeptide having kaurenoic acid 13-hydroxylase activity and whereby expression of the nucleotide sequence(s) confer(s) on the microorganism the ability to produce at least steviol; and b. recovering the diterpene or glycosylated diterpene.

Recombinant microorganisms, plants, and plant cells are disclosed that have been engineered to express novel recombinant genes encoding steviol biosynthetic enzymes and UDP-glycosyltransferases (UGTs). Such microorganisms, plants, or plant cells can produce steviol or steviol glycosides, e.g., rubusoside or Rebaudioside A, which can be used as natural sweeteners in food products and dietary supplements.

The present invention relates a variant polypeptide having kaurenoic acid 13-hydroxylase activity, which variant polypeptide comprises an amino acid sequence which, when aligned with a kaurenoic acid 13-hydroxylase comprising the sequence set out in SEQ ID NO: 1, comprises at least one substitution of an amino acid residue corresponding to any of amino acids 72, 85, 108, 127, 129, 141, 172, 195, 196, 197, 199, 226, 236, 291, 302, 361 or 464, said positions being defined with reference to SEQ ID NO: 1 and wherein the variant has one or more modified properties as compared with a reference polypeptide having kaurenoic acid 13-hydroxylase activity. A variant polypeptide of the invention may be used in a recombinant host for the production of steviol or a steviol glycoside.

Recombinant microorganisms are disclosed that produce steviol glycosides and have altered expression of one or more endogenous transporter or transcription factor genes or that overexpress one or more heterologous transporters, leading to increased excretions of steviol glucosides of interest.

Provided herein are genetically modified host cells, compositions, and methods for improved production of steviol glycosides. The host cells are genetically modified to contain a heterologous nucleic acid that expresses novel and optimized variants of UGT76G1. The host cell further contains one or more heterologous nucleotide sequence encoding further enzymes of a pathway capable of producing one or more steviol glycosides in the host cell. The host cells, compositions, and methods described herein provide an efficient route for the heterologous production of rebaudioside M.

The invention relates to recombinant microorganisms and methods for producing steviol glycosides and steviol glycoside precursors.