Oligonucleotide sequence for use in pathway engineering
The present invention comprises a novel artificial oligonucleotide sequence which can initiate the transcription of a gene under various conditions at a high level. Further the invention relates to a recombinant DNA fragment comprising the artificial oligonucleotide sequence, an expression plasmid comprising the recombinant DNA fragment and a host cell transformed with the recombinant DNA fragment.
1. An oligonucleotide comprising a sequence at least 90% identical to SEQ ID NO: 1; wherein said oligonucleotide, when present in yeast cells cultivated in the presence of glucose, mannose, ethanol, glycerol, or xylose, increases growth of the yeast cells.
2. The oligonucleotide of claim 1 , wherein said sequence is at least 95% identical to SEQ ID NO: 1.
3. The oligonucleotide of claim 2 , wherein said sequence is at least 98% identical to SEQ ID NO: 1.
4. The oligonucleotide of claim 3 , wherein said sequence is at least 99% identical to SEQ ID NO: 1.
5. The oligonucleotide of claim 1 , wherein said sequence is selected from the group consisting of SEQ ID NOS: 2-7.
6. The oligonucleotide of claim 1 , wherein the oligonucleotide, when present in yeast cells cultivated in the presence of glucose, mannose, ethanol, glycerol, or xylose, increases expression of XylA mRNA in the cells.
7. The oligonucleotide of claim 6 , wherein the increase in XylA mRNA expression is about 4-fold to about 29-fold.
8. The oligonucleotide of claim 1 , wherein the oligonucleotide, when present in yeast cells cultivated in the presence of glucose, mannose, ethanol, glycerol, or xylose, increases expression of xylose isomerase enzyme activity in the cells.
9. The oligonucleotide of claim 8 , wherein the increase in xylose isomerase enzyme activity expression is about 14-fold to about 25-fold.
10. A recombinant DNA fragment comprising said sequence of claim 1 .
11. A yeast cell expression plasmid comprising at least one recombinant DNA fragment of claim 10 .
12. A yeast cell comprising the plasmid of claim 11 .