title: Fatty alcohol production inLipomyces starkeyiandYarrowia lipolytica.
abstract: BACKGROUND
  Current biological pathways to produce biofuel intermediates amenable to separations and catalytic upgrading to hydrocarbon fuels are not cost effective. Previously, oleaginous yeasts have been investigated primarily for lipid production. However, yeasts store neutral lipids intracellularly making recovery difficult and expensive. In addition, once recovered from the cells, lipids are difficult to blend directly with the existing fuels without upgrading. We have, therefore, begun to investigate secreted fatty acid-derived products which can be easily recovered and upgraded to fuels.
  
  
  RESULTS
  In this study, we successfully demonstrate the production of fatty alcohols by the oleaginous yeasts,Yarrowia lipolyticaandLipomyces starkeyi, through expression of the fatty acyl-CoA reductase gene fromMarinobactor aquaeoleiVT8. This strategy resulted in the production of 167 and 770 mg/L of fatty alcohols in shake flask fromY. lipolyticaandL starkeyi, respectively. When using a dodecane overlay during fermentation, 92 and 99% of total fatty alcohols produced byY. lipolyticaandL. starkeyi, respectively, were extracted into the dodecane phase, which compares favorably to the 3 and 50% recovered, respectively, without the dodecane layer. In both oleaginous yeasts, long chain length, saturated fatty alcohols, i.e., hexadecanol (C16:0) and octadecanol (C18:0), were predominant and accounted for more than 85% of the total fatty alcohols produced. To the best of our knowledge, this is the first report of fatty alcohol production inL. starkeyi.
  
  
  CONCLUSIONS
  This work demonstrates that the oleaginous yeasts,Y. lipolyticaandL. starkeyi, can serve as platform organisms for the production of fatty acid-derived biofuels and bioproducts.
authors: Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401 USA.
authors: Wei
authors: W
authors: Wang
authors: Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401 USA.
authors: Hui
authors: H
authors: Wei
authors: National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO 80401 USA.
authors: Eric
authors: E
authors: Knoshaug
authors: National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO 80401 USA.
authors: Stefanie
authors: S
authors: Van Wychen
authors: Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401 USA.
authors: Qi
authors: Q
authors: Xu
authors: Biosciences Center, National Renewable Energy Laboratory, Golden, CO 80401 USA.
authors: Michael E
authors: ME
authors: Himmel
authors: National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO 80401 USA.
authors: Min
authors: M
authors: Zhang
keywords: Fatty alcohols; Lipomyces starkeyi; Metabolic engineering; Oleaginous yeasts; Yarrowia lipolytica