Recombinant oleandolide polyketide synthase

Abstract

Recombinant DNA compounds that encode all or a portion of the oleandolide polyketide synthase are used to express recombinant polyketide synthase genes in host cells for the production of oleandolide, oleandolide derivatives, and polyketides that are useful as antibiotics and motilides.

1 . An isolated recombinant DNA compound that comprises a coding sequence for a domain of a loading module or any one of extender modules one through four, inclusive of an oleandolide polyketide synthase (PKS).  
     
     
         2 . The isolated recombinant DNA compound of  claim 1 , wherein said domain is selected from the group consisting of a thioesterase domain, a KS Q  domain, an AT domain, a KS domain, an ACP domain, a KR domain, a DH domain and an ER domain.  
     
     
         3 . The isolated recombinant DNA compound of  claim 2  that comprises the coding sequence for a loading module and extender modules one and two of the oleandolide PKS.  
     
     
         4 . The isolated recombinant DNA compound of  claim 2  that comprises the coding sequence for the loading module and all six extender modules.  
     
     
         5 . An isolated recombinant DNA compound that comprises a coding sequence for a domain of a loading module or any one of extender modules one through six, inclusive of an oleandolide polyketide synthase (PKS) operably linked to a promoter.  
     
     
         6 . The isolated recombinant DNA compound of  claim 5 , wherein said coding sequence encodes a loading module or any one of extender modules one through four, inclusive, of oleandolide PKS.  
     
     
         7 . The isolated recombinant DNA compound of  claim 5  that is a recombinant DNA expression vector that further comprises an origin of replication or a segment of DNA that enables chromosomal integration.  
     
     
         8 . The recombinant DNA expression vector of  claim 7  that codes for expression of a PKS in Streptomyces host cells.  
     
     
         9 . A recombinant host cell selected from the group consisting of Streptomyces host cells and Saccharopolyspora host cells that comprises a recombinant DNA expression vector of  claim 7 .  
     
     
         10 . The recombinant DNA expression vector of  claim 7  that encodes a hybrid PKS comprising at least a portion of an oleandolide PKS gene and at least a portion of a second PKS gene for a macrolide aglycone other than oleandolide.  
     
     
         11 . The recombinant DNA compound of  claim 10 , wherein said second PKS gene is a DEBS gene.  
     
     
         12 . The recombinant DNA compound of  claim 11 , wherein said hybrid PKS comprises a loading module and any one of extender modules one through four, inclusive, of oleandolide PKS and an extender module of DEBS.  
     
     
         13 . The recombinant DNA compound of  claim 10 , wherein said hybrid PKS comprises a loading module and any one of extender modules one through four, inclusive, of oleandolide PKS and an extender module of narbonolide PKS.  
     
     
         14 . A recombinant host cell, which in its untransformed state does not produce oleandolide, that comprises a recombinant DNA expression vector of  claim 11  and said cell produces a macrolide aglycone synthesized by said hybrid PKS.  
     
     
         15 . The recombinant host cell of  claim 14  that is  Streptomyces lividans.    
     
     
         16 . The recombinant host cell of  claim 14  that is  Saccharopolyspora erythraea.    
     
     
         17 . The recombinant host cell of  claim 13 , wherein said oleandolide PKS has a non-functional KS domain in extender module one.  
     
     
         18 . The recombinant host cell of  claim 17  that is  Streptomyces coelicolor  or  Streptomyces lividans.    
     
     
         19 . The recombinant host cell of  claim 17  that is  Saccharopolyspora erythraea.    
     
     
         20 . A method for producing a polyketide in a cell, which method comprises transforming the cell with a recombinant expression vector that encodes at least a portion of an oleAI, oleAII, or oleAIII gene.