| 摘要 |
Described are engineered strains of the oleaginous yeast Yarrowia lipolytica capable of producing an oil comprising greater than 50 weight percent of eicosapentaenoic acid ["EPA"], an ?-3 polyunsaturated fatty acid, measured as a weight percent of total fatty acids ["% TFAs"] and having a ratio of at least 3.1 of EPA % TFAs, to linoleic acid, measured as % TFAs. These strains over-express at least one ?9 elongase/?8 desaturase multizyme, in addition to other heterologous ?9 elongases, ?8 desaturases, ?5 desaturases, ?17 desaturases, ?12 desaturases, C16/18 elongases, and optionally over-express diacylglycerol cholinephosphotransferases, malonyl CoA synthetases and/or acyl-CoA lysophospholipid acyltransferases. The expression of at least one peroxisome biogenesis factor protein is down-regulated. Methods for producing EPA within said host cells, oils obtained from the cells, and products therefrom are claimed. |
