A newly identified fatty alcohol oxidase gene is mainly responsible for the oxidation of long-chain ω-hydroxy fatty acids inYarrowia lipolytica

Abstract

Nine potential (fatty) alcohol dehydrogenase genes and one alcohol oxidase gene were identified in Yarrowia lipolytica by comparative sequence analysis. All relevant genes were deleted in Y. lipolytica H222ΔP which is lacking β-oxidation. Resulting transformants were tested for their ability to accumulate ω-hydroxy fatty acids and dicarboxylic acids in the culture medium. The deletion of eight alcohol dehydrogenase genes (FADH, ADH1-7), which may be involved in ω-oxidation, led only to a slightly increased accumulation of ω-hydroxy fatty acids, whereas the deletion of the fatty alcohol oxidase gene (FAO1), which has not been described yet in Y. lipolytica, exhibited a considerably higher effect. The combined deletion of the eight (fatty) alcohol dehydrogenase genes and the alcohol oxidase gene further reduced the formation of dicarboxylic acids. These results indicate that both (fatty) alcohol dehydrogenases and an alcohol oxidase are involved in ω-oxidation of long-chain fatty acids whereby latter plays the major role. This insight marks the first step toward the biotechnological production of long-chain ω-hydroxy fatty acids with the help of the nonconventional yeast Y. lipolytica. The overexpression of FAO1 can be further used to improve existing strains for the production of dicarboxylic acids.

Combinatorial Engineering of Yarrowia lipolytica as a Promising Cell Biorefinery Platform for the de novo Production of Multi-Purpose Long Chain Dicarboxylic Acids

“…In the same fashion, amplification of the P450 reductase gene was found to enhance LCDCA production from C. tropicalis [14]. Similarly, it was reported that the overexpression of YlFAO1 improves LCDCA production from exogenous hydrophobic substrates [42]. This accords with the contribution of FAO1 to diacid production observed in C. tropicalis [95].…”

Fatty Aldehyde Dehydrogenase Multigene Family Involved in the Assimilation of n-Alkanes in Yarrowia lipolytica

“…The missing link in the n-alkane assimilation pathway is the enzyme(s) that catalyze(s) the oxidation of fatty alcohols to fatty aldehydes. It has been reported that a deletion mutant lacking the alcohol dehydrogenase genes, FADH and ADH1-ADH7, and a fatty alcohol oxidase gene, FAO1, exhibited defects in the oxidation of long chain -hydroxy fatty acids, but was still able to metabolize n-dodecane and oxidize 1-dodecanol (26). It is thus possible that multiple genes are involved in the oxidation of fatty alcohols, as is the case for n-alkanes and fatty aldehydes.…”

“…An orthologous gene, however, has not been identified in the genome sequence of Y. lipolytica. It was recently shown that alcohol dehydrogenase genes, FADH and ADH1-ADH7, and a fatty alcohol oxidase gene, FAO1, are involved in the oxidation of -hydroxy fatty acids in Y. lipolytica; however, the deletion mutant strain lacking all these genes is able to oxidize dodecanol (26). FALDH activities have been reported in C. tropicalis, Y. lipolytica, and Candida intermedia (27)(28)(29), but the enzymes catalyzing the reactions remain unidentified.…”

Characterization of threeYarrowia lipolyticastrains in respect to different cultivation temperatures and metabolite secretion

“…The second minimal medium YSM triggers the lipid accumulation in Y. lipolytica due to its low nitrogen content as well as high glucose concentration (50 g L -1 ). Therefore it was used to analyze lipid production of the two wild type strains in comparison to H222Δ pox1-6 harbouring a blockade of the fatty acid degradation (Gatter et al 2014) .…”

“…Schauer, Ernst-Moritz-Arndt University Greifswald, Germany) referred to as 63 and 1889, respectively. Additionally, the laboratory strain H222Δ pox1-6 was used (Gatter et al 2014) .…”