Biological methods for modifying cellular carbon flux

A genetically modified cell, comprising:

• one or more genetic modifications that increase the amount or activity of a polypeptide involved in a reaction that generates cytosolic acetyl-CoA, cytosolic malonyl-CoA or peroxisomal acetate in the cell, wherein the cell:
• (i) is able to convert fatty acids or alkanes to dicarboxylic acid through ω-oxidation,
• (ii) does not express a cytosolic acyl-CoA synthetase activity or has been genetically modified to express reduced levels of acyl-CoA synthetase activity relative to the cell that has not been genetically modified to express reduced levels of acyl-CoA synthetase activity and
• (iii) comprises heterologous nucleic acid encoding one or more polypeptides that have acyl-CoA thioesterase activity, wherein the amino acid sequence of the polypeptide that has acyl-CoA thioesterase activity comprises an amino acid sequence that is substantially similar to the amino acid sequence of SEQ ID NO:32;
• further comprising one or more genetic modifications that reduce the amount or activity of a carnitine acetyltransferase in the mitochondria relative to a cell that does not comprise the genetic modification,
• wherein at least one of the one or more genetic modifications that alter the transport of acetyl-carnitine in the cell comprise a disrupted endogenous gene encoding a polypeptide providing for conversion of acetyl-carnitine to acetyl-CoA inside the mitochondria wherein said polypeptide is a mitochondrial carnitine acetyltransferase, and addition of a heterologous nucleic acid comprising a promoter operably linked to nucleic acid encoding the polypeptide providing for conversion of acetyl-carnitine to mitochondrial acetyl-CoA, wherein the mitochondrial carnitine acetyltransferase has reduced enzymatic activity relative to the endogenous mitochondrial carnitine acetyltransferase and comprises an amino acid sequence that is substantially similar to an amino acid sequence selected from SEQ ID NO:
• 10, SEQ ID NO:
• 11 and SEQ ID NO:
• 1Z wherein the promoter provides for reduced expression of the polypeptide providing for conversion of acetyl-carnitine to mitochondrial acetyl-CoA in the cell relative to a cell that does not have the genetic modification(s), wherein the promoter is a glucose-6-phosphate isomerase gene promoter, and
• wherein the cell is a yeast selected from the group consisting of Candida viswanathii and Candida tropicalis.