Production of dihydrosterculic acid and derivatives thereof

A recombinant plant cell, algal cell or fungal cell comprising an exogenous polynucleotide encoding a cyclopropane fatty acid synthetase (CPFAS), wherein extractable oil in the cell contains dihydrosterculic acid (DHS) and/or a fatty acid derivative thereof, and wherein the polynucleotide is operably linked to one or more promoters that are capable of directing expression of the polynucleotide in the cell, and wherein the cell has one or more of the following features,

• i) at least about 3%, or at least about 5%, or at least about 7%, or at least about 10%, or at least about 12%, or at least about 15%, of the total fatty acid in the extractable oil in the cell is DHS and/or a fatty acid derivative thereof,
• ii) the CPFAS converts oleic acid to DHS in the cell with a conversion efficiency of at least about 45%, or at least about 50% or at least about 55%,
• iii) the ratio of oleic acid to DHS and/or fatty acid derivative thereof in the extractable oil in the cell is less than about 2:1, preferably less than about 1.5:1, more preferably less than about 1:1, or
• iv) the CPFAS comprises amino acids having a sequence as provided in any one of SEQ ID NOs:
• 1, or 21 to 28, a biologically active fragment thereof, or an amino acid sequence which is at least 30% identical to any one or more of SEQ ID NOs:
• 1, or 21 to 28, wherein the CPFAS is no longer than about 600 amino acids in length.

A method of selecting a nucleic acid molecule encoding a truncated cyclopropane synthetase (CPFAS), the method comprising

• i) obtaining a nucleic acid molecule operably linked to a promoter, wherein the nucleic acid encodes a truncated variant of a CPFAS,
• ii) introducing the nucleic acid molecule into a plant cell, algal cell or fungal cell in which the promoter is active;
• iii) expressing the nucleic acid molecule in the cell;
• iv) analysing the fatty acid composition of the cell;
• and
• v) selecting the nucleic acid molecule by selecting a cell having one or more of the following features,
• a) at least about 3%, or at least about 5%, or at least about 7%, or at least about 10%, or at least about 15%, of the total fatty acid in extractable oil in the cell is DHS and/or a fatty acid derivative thereof,
• b) converts oleic acid to DHS in the cell with a conversion efficiency of at least about 45%, or at least about 50% or at least about 55%, or
• c) comprises a ratio of oleic acid to DHS and/or fatty acid derivative thereof in extractable oil in the cell less about than 2:1, preferably less than about 1.5:1, more preferably less than about 1:1.