Microorganisms for producing glycogen and methods of using same

1. A recombinant microorganism modified with respect to a native microorganism, the recombinant microorganism comprising a recombinant nucleic acid configured to express a glucose-1-phosphate adenylyltransferase, wherein the recombinant microorganism:

is a cyanobacterium;

exhibits enhanced glucose-1-phosphate adenylyltransferase activity compared to the native microorganism; and

produces an increased amount of glycogen compared to the native microorganism while having a growth rate of at least a growth rate of the native microorganism when grown photoautotrophically in the presence of light and 10% CO 2 .

2. The recombinant microorganism of claim 1 , wherein the glucose-1-phosphate adenylyltransferase is allosterically regulated by a compound selected from the group consisting of adenosine diphosphate and adenosine monophosphate.

3. The recombinant microorganism of claim 1 , wherein the glucose-1-phosphate adenylyltransferase comprises a sequence at least 90% identical to SEQ ID NO:2.

4. The recombinant microorganism of claim 1 , wherein the glucose-1-phosphate adenylyltransferase comprises a glycine at a position corresponding to position 336 of SEQ ID NO:2.

5. The recombinant microorganism of claim 1 , wherein the nucleic acid comprises a glucose-1-phosphate adenylyltransferase coding sequence operably connected to a promoter not operably connected to the coding sequence in nature.

6. The recombinant microorganism of claim 5 , wherein the promoter is an inducible promoter.

7. The recombinant microorganism of claim 5 , wherein the promoter is a constitutive promoter.

8. The recombinant microorganism of claim 1 , wherein the recombinant microorganism exhibits a native glycogen synthase expression level.

9. The recombinant microorganism of claim 1 , wherein the recombinant microorganism exhibits native glycogen synthase activity.

10. The recombinant microorganism of claim 1 , wherein the recombinant microorganism exhibits a native 1,4-alpha-glucan-branching enzyme expression level.

11. The recombinant microorganism of claim 1 , wherein the recombinant microorganism exhibits native 1,4-alpha-glucan-branching enzyme activity.

12. The recombinant microorganism of claim 1 , wherein the recombinant microorganism is capable of producing glycogen as a mass percent of dry cell weight (DCW) in an amount of at least about 25% DCW.

13. A method of producing glycogen comprising culturing the recombinant microorganism of claim 1 .

14. The recombinant microorganism of claim 1 , wherein the recombinant microorganism exhibits a native 1,4-alpha-glucan-branching enzyme expression level and native 1,4-alpha-glucan-branching enzyme activity, and wherein the recombinant microorganism is capable of producing glycogen as a mass percent of dry cell weight (DCW) in an amount of at least about 25% DCW.

15. The recombinant microorganism of claim 14 , wherein the glucose-1-phosphate adenylyltransferase comprises a glycine at a position corresponding to position 336 of SEQ ID NO:2 and is allosterically regulated by a compound selected from the group consisting of adenosine diphosphate and adenosine monophosphate.

16. The recombinant microorganism of claim 14 , wherein the glucose-1-phosphate adenylyltransferase comprises a sequence at least 90% identical to SEQ ID NO:2.

17. The recombinant microorganism of claim 14 , wherein the nucleic acid comprises a glucose-1-phosphate adenylyltransferase coding sequence operably connected to a promoter not operably connected to the coding sequence in nature.

18. The recombinant microorganism of claim 14 , wherein the recombinant microorganism exhibits a native glycogen synthase expression level.

19. The recombinant microorganism of claim 14 , wherein the recombinant microorganism exhibits native glycogen synthase activity.

20. A method of producing glycogen comprising culturing the recombinant microorganism of claim 14 .