oil equivalents, the use of which was previously limited by its high price resulting in its restriction to medical and cosmetic applications. In addition, the knowledge gathered so far on the substrate specificity of different forms of wax synthase allows for scientists to explore the use of yeast cells, in particular Saccharomyces cerevisiae, in the production of biodiesel fuels. "S. Cerevisiae" is a well-documented industrial microorganism and is easy to cultivate, manipulate genetically, quick growth, and fatty acid metabolism, making it an ideal candidate for the expression of wax esters. S. Cerevisiae is further suitable as for this task as they produce the necessary reactants for wax synthases to create wax esters. Scientists have investigated the possibility of expressing different wax synthase genes, including those of A. baylyi ADP1, M. hydrocarbonoclasticus DSM 8798, R. opacus PD630, M. musculus C57BL/6 and P. arcticus 273-4, in S. cerevisiae, and found that that of Marinobacter hydrocarbonoclasticus DSM 8798 was the most effective since it showed highest relative preference for ethanol, thus allowing for the production of biodiesel fuels, in part taking advantage of the enzyme’s promiscuous nature. References EC 2.3.1 Enzymes of unknown structure