Xylose isomerases and their uses

Patent metadata

Field	Value
Publication number	US-9982249-B2
Application number	US-201314417080-A
Country	US
Kind code	B2
Filing date	Jul 23, 2013
Priority date	Jul 24, 2012
Publication date	May 29, 2018
Grant date	May 29, 2018

Abstract

This disclosure relates to novel xylose isomerases and their uses, particularly in fermentation processes that employ xylose-containing media.

First claim

What is claimed is:

1. An isolated nucleic acid sequence comprising a nucleotide sequence having at least 90%, at least 93%, at least 95%, at least 96%, at least 98%, or at least 99% sequence identity, or having 100% sequence identity, to the nucleotide sequence of SEQ ID NO: 245 or to a portion thereof encoding a xylose isomerase catalytic or dimerization domain, wherein the nucleic acid encodes a polypeptide with at least one substitution relative to the polypeptide having the sequence of SEQ ID NO: 96 or at least one heterologous amino acid flanking the N-terminal or the C-terminal.

2. The nucleic acid sequence of claim 1 , which is codon optimized for expression in a eukaryotic cell.

3. The nucleic acid sequence of claim 1 , which is codon optimized for expression in yeast.

4. A vector comprising the nucleic acid sequence of claim 1 .

5. The vector of claim 4 , which further comprises an origin of replication.

6. The vector of claim 4 , which further comprises a promoter sequence operably linked to said nucleic acid sequence.

7. The vector of claim 6 , wherein the promoter sequence is operable in yeast.

8. The vector of claim 6 , wherein the promoter sequence is operable in filamentous fungi.

9. A recombinant cell engineered to express a polypeptide encoded by the nucleic acid sequence of claim 1 .

10. The recombinant cell of claim 9 , wherein the cell is a eukaryotic cell.

11. The recombinant cell of claim 9 , wherein the cell is a yeast cell.

12. The recombinant cell of claim 11 , wherein the yeast cell is a yeast cell of the genus Saccharomyces, Kluyveromyces, Candida, Pichia, Schizosaccharomyces, Hansenula, Klockera, Schwanniomyces, Issatchenkia or Yarrowia.

13. The recombinant cell of claim 11 , wherein the yeast cell is of the species S. cerevisiae, S. bulderi, S. barnetti, S. exiguus, S. uvarum, S. diastaticus, K lactis, K. marxiames or K. fragili , or Issatchenkia orientalis.

14. The recombinant cell of claim 13 , wherein the cell is a S. cerevisiae cell.

15. The recombinant cell of claim 14 , comprising one or more genetic modifications resulting in at least one, any two, any three, any four or all of the following phenotypes:
(a) an increase in transport of xylose into the cell;
(b) an increase in xylulose kinase activity;
(c) an increase in aerobic growth rate on xylose;
(d) an increase in flux through the pentose phosphate pathway into glycolysis;
(e) a decrease in aldose reductase activity;
(f) a decrease in sensitivity to catabolite repression;
(g) an increase in tolerance to ethanol, intermediates, osmolality or organic acids; and
(h) a reduced production of byproducts.

16. The recombinant cell of claim 15 , wherein one or more genetic modifications result in increased expression levels of one or more of a hexose or pentose transporter, a xylulose kinase, an enzyme from the pentose phosphate pathway, a glycolytic enzyme and an ethanologenic enzyme.

17. A host cell transformed with the vector of claim 4 .

18. The host cell of claim 17 which is a prokaryotic cell.

19. The host cell of claim 18 which is a bacterial cell.

20. The host cell of claim 17 which is a eukaryotic cell.

Assignees

• Bp Corp North America Inc

Inventors

• Nunn David Neal
• Luginbuhl Peter
• Lee Ling
• Burja Adam Martin
• Bartnek Jon Peter Flash

Classifications

• C12P7/16

  Butanols · CPC title

• C12P7/54

  Acetic acid (vinegar C12J) · CPC title

• C12P7/10

  substrate containing cellulosic material · CPC title

• Y02E50/13

  Cross-Sectional Technologies · mapped topic

• Y02E50/10

  Biofuels, e.g. bio-diesel · CPC title