Glucosyltransferase enzymes for production of glucan polymers
Reaction solutions are disclosed herein comprising water, sucrose and a glucosyltransferase enzyme that synthesizes poly alpha-1,3-glucan. The glucosyltransferase enzyme can synthesize insoluble glucan polymer having at least 50% alpha-1,3 glycosidic linkages and a number average degree of polymerization of at least 100. Further disclosed are methods of using such glucosyltransferase enzymes to produce insoluble poly alpha-1,3-glucan.
1. A composition comprising (i) an insoluble poly alpha-1,3-glucan having at least 90% alpha-1,3 glycosidic linkages, and (ii) a genetically engineered cell that expresses an isolated glucosyltransferase enzyme comprising an amino acid sequence that is at least 90% identical to SEQ ID NO:4.
2. The composition of claim 1 , wherein said insoluble poly alpha-1,3-glucan has a number average degree of polymerization of at least 100.
3. The composition of claim 1 , wherein said insoluble poly alpha-1,3-glucan has at least 95% alpha-1,3 glycosidic linkages.
4. The composition of claim 1 , wherein said insoluble poly alpha-1,3-glucan has at least 97% alpha-1,3 glycosidic linkages.
5. The composition of claim 1 , wherein said insoluble poly alpha-1,3-glucan has at least 99% alpha-1,3 glycosidic linkages.
6. The composition of claim 1 , wherein said insoluble poly alpha-1,3-glucan has about 100% alpha-1,3 glycosidic linkages.
7. The composition of claim 1 , wherein said glucosyltransferase enzyme comprises an amino acid sequence that is at least 93% identical to SEQ ID NO:4.
8. The composition of claim 1 , wherein said glucosyltransferase enzyme comprises an amino acid sequence that is at least 95% identical to SEQ ID NO:4.
9. The composition of claim 1 , wherein said glucosyltransferase enzyme comprises an amino acid sequence that is at least 97% identical to SEQ ID NO:4.
10. The composition of claim 1 , wherein said glucosyltransferase enzyme comprises an amino acid sequence that is at least 98% identical to SEQ ID NO:4.
11. The composition of claim 1 , wherein said glucosyltransferase enzyme comprises an amino acid sequence that is at least 99% identical to SEQ ID NO:4.
12. The composition of claim 1 , wherein a heterologous amino acid sequence of 1-300 residues is at the N-terminus and/or C-terminus of said glucosyltransferase enzyme.
13. The composition of claim 1 , wherein the composition further comprises fructose.
14. The composition of claim 13 , wherein the composition further comprises glucose, sucrose, or leucrose.
15. The composition of claim 13 , wherein the composition further comprises glucose, sucrose and leucrose.
16. The composition of claim 1 , wherein the genetically engineered cell is a bacteria cell.
17. The composition of claim 16 , wherein the bacteria cell is an E. coli cell.
18. The composition of claim 16 , wherein the bacteria cell is a Bacillus species cell.
19. The composition of claim 1 , wherein the genetically engineered cell is a yeast cell.
20. The composition of claim 19 , wherein the yeast cell is a Saccharomyces species cell.
21. The composition of claim 19 , wherein the yeast cell is a Pichia species cell.
22. The composition of claim 1 , wherein composition further comprises water.