STEVIOL GLYCOSIDE TRANSPORT
A recombinant host capable of producing a steviol glycoside which overexpresses a polypeptide which mediates steviol glycoside transport and which polypeptide comprises the amino acid sequence set forth in SEQ ID NO: 35 or SEQ ID NO: 38 or an amino acid sequence having at least about 50% sequence identity to either thereto. A recombinant host capable of producing a steviol glycoside which has been modified, preferably in its genome, to result in a deficiency in the production of a polypeptide which mediates steviol glycoside transport and which polypeptide comprises the amino acid sequence set forth in SEQ ID NO: 35 or SEQ ID NO: 38 or an amino acid sequence having at least about 50% sequence identity to either thereto.
1 . A recombinant host capable of producing a steviol glycoside which overexpresses a polypeptide which mediates steviol glycoside transport and which polypeptide comprises the amino acid sequence set forth in SEQ ID NO: 35 or SEQ ID NO: 38 or an amino acid sequence having at least about 50% sequence identity to either thereto.
2 . A recombinant host capable of producing a steviol glycoside which has been modified, optionally in its genome, to result in a deficiency in the production of a polypeptide which mediates steviol glycoside transport and which polypeptide comprises the amino acid sequence set forth in SEQ ID NO: 35 or SEQ ID NO: 38 or an amino acid sequence having at least about 50% sequence identity to either thereto.
3 . The recombinant host according to claim 1 , which comprises a recombinant nucleic acid encoding a polypeptide which comprises the amino acid sequence set forth in SEQ ID NO: 35 or SEQ ID NO: 38 or an amino acid sequence having at least about 50% sequence identity to either thereto.
4 . The recombinant host according to claim 1 , which further comprises one or more recombinant 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.
5 . The recombinant host according to claim 1 , which further comprises a recombinant nucleic acid sequence encoding a polypeptide having NADPH-cytochrome p450 reductase activity.
6 . The recombinant host according to claim 1 , which further comprises a recombinant nucleic acid sequence encoding one or more of:
(i) a polypeptide having UGT74G1 activity;
(ii) a polypeptide having UGT2 activity;
(iii) a polypeptide having UGT85C2 activity; and
(iv) a polypeptide having UGT76G1 activity.
7 . The recombinant host according to claim 1 , wherein the host belongs to one of the genera Saccharomyces, Aspergillus, Pichia, Kluyveromyces, Candida, Hansenula, Humicola, Issatchenkia, Trichosporon, Brettanomyces, Pachysolen, Yarrowia, Yamadazyma , or Escherichia.
8 . The recombinant host according to claim 7 , wherein the recombinant host is a Saccharomyces cerevisiae cell, a Yarrowia lipolitica cell, a Candida krusei cell, an Issatchenkia orientalis cell or an Escherichia coli cell.
9 . The recombinant host according to claim 1 , wherein the ability of the host to produce geranylgeranyl diphosphate (GGPP) is upregulated.
10 . The recombinant host according to claim 1 , which further comprises a nucleic acid sequence encoding one or more of:
a polypeptide having hydroxymethylglutaryl-CoA reductase activity; or
a polypeptide having farnesyl-pyrophosphate synthetase activity.
11 . A recombinant host capable of producing a steviol glycoside which overexpresses a heterologous polypeptide which mediates steviol glycoside transport.
12 . A process for the preparation of a steviol glycoside which comprises fermenting the recombinant host according to claim 1 in a suitable fermentation medium and, optionally, recovering the steviol glycoside.
13 . The process according to claim 12 for the preparation of a steviol glycoside, wherein the process is carried out on an industrial scale.
14 . A fermentation broth comprising a steviol glycoside obtainable by the process according to claim 12 .
15 . A steviol glycoside obtained by the process according to claim 12 .
16 . A composition obtainable by the process according to claim 12 .
17 . A foodstuff, feed or beverage which comprises the steviol glycoside according to claim 15 .