Thioesterases and cells for production of tailored oils

Abstract

The invention features plant acyl-ACP thioesterase genes of the FatB class and proteins encoded by these genes. The genes are useful for constructing recombinant host cells having altered fatty acid profiles. Oleaginous microalga host cells with the new genes or previously identified FatB genes are disclosed. The microalgae cells produce triglycerides with useful fatty acid profiles.

1 . An isolated nucleic acid having at least 80% sequence identity to any of SEQ ID NOS: 21, 27, 30, 69, 72, or 78 or any equivalent sequences by virtue of the degeneracy of the genetic code. 
     
     
         2 . An isolated nucleic acid sequence encoding a protein having at least 80% sequence identity to any of SEQ ID NO: 22, 25, 28, 67, 70, or 77, or a fragment thereof having acyl-ACP thioesterase activity. 
     
     
         3 . The isolated nucleic acid of  claim 2 , wherein, the protein has acyl-ACP thioesterase activity operable to alter the fatty acid profile of an oil produced by a recombinant cell comprising that sequence. 
     
     
         4 . A method of producing a recombinant cell that produces an altered fatty acid profile, the method comprising transforming the cell with a nucleic acid according to  claim 1 . 
     
     
         5 . A host cell produced by the method of  claim 4 . 
     
     
         6 . The host cell of  claim 5 , wherein the host cell is selected from a plant cell, a microbial cell, and a microalgal cell. 
     
     
         7 . A method for producing an oil or oil-derived product, the method comprising cultivating a host cell of  claim 5 , and extracting oil produced thereby, optionally wherein the cultivation is heterotrophic growth on sugar. 
     
     
         8 . The method of  claim 7 , further comprising producing a fatty acid, fuel, chemical, or other oil-derived product from the oil. 
     
     
         9 . An oil produced by the method of  claim 7 , optionally having a fatty acid profile comprising at least 20% C14 or C16 fatty acids. 
     
     
         10 . An oil-derived product produced by the method of  claim 8 . 
     
     
         11 . The oil of  claim 10 , wherein the oil is produced by a microalgae and optionally, lacks C24-alpha sterols.