초록
<P><B>Abstract</B></P> <P>Fatty alcohols are important components of a vast array of surfactants, lubricants, detergents, pharmaceuticals and cosmetics. We have engineered <I>Saccharomyces cerevisiae</I> to produce 1-hexadecanol by expressing a fatty acyl-CoA reductase (FAR) from barn owl (<I>Tyto alba</I>). In order to improve fatty alcohol production, we have manipulated both the structural genes and the regulatory genes in yeast lipid metabolism. The acetyl-CoA carboxylase gene (<I>ACC1</I>) was over-expressed, which improved 1-hexadecanol production by 56% (from 45mg/L to 71mg/L). Knocking out the negative regulator of the <I>INO1</I> gene in phospholipid metabolism, RPD3, further enhanced 1-hexadecanol production by 98% (from 71mg/L to 140mg/L). The cytosolic acetyl-CoA supply was next engineered by expressing a heterologous ATP-dependent citrate lyase, which increased the production of 1-hexadecanol by an additional 136% (from 140mg/L to 330mg/L). Through fed-batch fermentation using resting cells, over 1.1g/L 1-hexadecanol can be produced in glucose minimal medium, which represents the highest titer reported in yeast to date.</P> <P><B>Highlights</B></P> <P> <UL> <LI> <I>Saccharomyces cerevisiae</I> was engineered to produce 1-hexadecanol by expressing FAR from barn owl. </LI> <LI> Both structural genes and regulatory genes of yeast lipid metabolism were engineered to increase the 1-hexadecanol production. </LI> <LI> Acetyl-CoA supply in cytoplasm was engineered to further increase 1-hexadecanol production. </LI> <LI> The 1-hexadecanol was produced at the highest reported titer (>1100mg/L) to date in yeast. </LI> </UL> </P>