Abstract: A microbial cell, which is genetically modified to increase the expression relative to the corresponding genetically unmodified cell of an AlkB alkane hydroxylase (Eb) having an amino acid sequence at least 95% identical with the amino acid sequence of SEQ ID NO: 1 and a wax-ester synthase (Ef) having an amino acid sequence at least 95% identical with the amino acid sequence of SEQ ID NO: 2. The cell does not have a genetic modification that increases formation of a carboxylic acid or a carboxylate ester from a simple carbon source.

Abstract: There is provided a microbial cell for producing at least one omega-functionalized carboxylic acid ester from at least one alkane, wherein the cell is genetically modified to increase the expression relative to the wild type cell of (i) Enzyme E1 capable of converting the alkane to the corresponding 1-alkanol; (ii) Enzyme E2 capable of converting the 1-alkanol of (i) to the corresponding 1-alkanal; (iii) Enzyme E3 capable of converting the 1-alkanal of (ii) to the corresponding alkanoic acid; (iv) Enzyme E4 capable of converting the alkanoic acid of (iii) to the corresponding alkanoic acid ester; and (iv) Enzyme E5 capable of converting the alkanoic acid ester of (iv) to the corresponding omega-hydroxy-alkanoic acid ester, and wherein the cell does not comprise a genetic modification that increases the expression relative to the wild type cell of at least one of the following enzymes E20-E24 selected from the group consisting of: E20 Acyl-ACP thioesterase, of EC 3.1.2.14 or EC 3.1.2.