Producing dicarboxylic acids using polyketide synthases
The present invention provides for a polyketide synthase (PKS) capable of synthesizing a dicarboxylic acid (diacid). Such diacids include diketide-diacids and triketide-diacids. The invention includes recombinant nucleic acid encoding the PKS, and host cells comprising the PKS. The invention also includes methods for producing the diacids.
1. A recombinant polyketide synthase (PKS) capable of synthesizing a dicarboxylic acid (diacid), said PKS comprising a loading module containing a beta-keto acyl carrier protein synthase Q domain (KS Q ) lacking decarboxylase activity, one or more extender modules and a thioesterase (TE) domain.
2. The PKS of claim 1 , wherein said diacid is pentane-1,5-dioic acid, and said PKS has a loading module that utilizes malonate and a single extender module that has a malonate-specific acyltransferase (AT) domain and a full set of reduction domains.
3. The PKS of claim 2 , wherein the loading module is from spiromycin, the single extender module is module 5 or module 6 from nystatin PKS or module 3 from the oligomycin PKS, and the TE domain is from erythromycin PKS.
4. The PKS of claim 1 , wherein said diacid is heptane-1,7-dioic acid; and said PKS has a loading module that utilizes malonate; a first and a second extender module, each of which has a malonate-specific acyltransferase (AT) domain; and a full set of reduction domains.
5. The PKS of claim 4 , wherein the loading module is from spiromycin, the first extender module is module 5 or module 6 from nystatin PKS or module 3 from the oligomycin PKS, the second extender module is module 5 from the epothilone PKS, and the TE domain is from erythromycin PKS.
6. The PKS of claim 1 , wherein said PKS comprises the loading module and module 1 of the spiramycin, oligomycin, or primaricin PKS; and the TE domain from erythromycin PKS or the TE domain encoded by the monCII gene; wherein the KS Q domain of the loading module is deleted or modified to inactivate the decarboxylase activity.
7. The PKS of claim 1 , wherein the diacid comprises from 1 to 10 ketide units.
8. The PKS of claim 7 , wherein the diacid comprises from 1 to 6 ketide units.
9. The PKS of claim 8 , wherein the diacid comprises from 1 to 3 ketide units.
10. The PKS of claim 9 , wherein the diacid is one described in Tables 2A-F and Tables 3A-KK.
11. A host cell comprising the PKS of claim 1 .
12. The host cell of claim 11 , wherein the host cell is a prokaryotic host cell.
13. The host cell of claim 12 , wherein the prokaryotic host cell is an E. coli or a Streptomyces sp. cell.
14. The host cell of claim 11 , wherein the host cell is a yeast host cell.