Hybrid polyketide synthases

A non-naturally occurring hybrid polyketide synthase (PKS) which synthesizes adipic acid, wherein the PKS comprises:

• (a) a first module that is a loading module that incorporates succinyl-CoA, wherein the first module comprises an aspartate-specific adenylation (A) domain from the non-ribosomal peptide synthetase (NRPS) from the calcium-dependent antibiotic (CPA) pathway from Saccharopolyspora erythraea linked to a peptidylcarrier protein (PCP) domain from the bleomycin pathway from Streptomyces verticillus;
• wherein the A domain comprises a glutamine substitution for the conserved Asp235 residue of the substrate-binding pocket as defined in the gramicidin S synthase phenylalanine-activating domain;
• and
• a second module comprising at least one extension module and a TE domain;
• or
• (b) a first module that is a loading module that incorporates succinyl-CoA, wherein the first module comprises a loading domain and ACP domain of a chondrochloren PKS in which a succinyl-CoA synthetase replaces a CoA ligase domain and
• a second module comprising at least one extension module and a TE domain;
• or
• (c) an etnangien loading module which incorporates succinate using a trans-AT domain;
• and
• (i) at least one heterologous extension module, and a TE domain:
• or
• (ii) extension module 1 from Sorangium cellulosum PKS in which DH-ER-KR domains are inserted between the ACP2 and ACP3;
• and a TE domain;
• or
• (iii) wherein the etnangien loading module has inactivated the KS domain joined to the KS domain of extension module 2 from Sorangium cellulosum PKS linked to a malonyl-specific AT domain joined to DH-ER-KR-ACP-TE domains;
• or
• (d) a loading module and at least three extension modules as set forth in FIG. 14, wherein the PKS produces the intermediates [a], [b], [c], and [d] set forth in FIG. 14, wherein the 9-carbon backbone of [d] is released from the ACP by the TE domain and converted to adipic and propionic acid by an esterase, an alcohol dehydrogenase, a flavin-binding family monooxygenase, and an aldehyde dehydrogenase as set forth in FIG. 13.