Isolation of a Delta5-fatty acid desaturase gene from Mortierella alpina.
Arachidonic acid (C20:4 Delta5,8,11,14) is a polyunsaturated fatty acid synthesized by the Delta5-fatty acid desaturation of di-homo-gamma-linolenic acid (C20:3 Delta8,11,14). In mammals, it is known to be a precursor of the prostaglandins and the leukotrienes but it is also accumulated by the filamentous fungus Mortierella alpina. We have isolated a cDNA encoding the Delta5-fatty acid desaturase from M. alpina via a polymerase chain reaction-based strategy using primers designed to the conserved histidine box regions of microsomal desaturases, and confirmed its function by expression in the yeast Saccharomyces cerevisiae. Analysis of the lipids from the transformed yeast demonstrated the accumulation of arachidonic acid. The M. alpina Delta5-desaturase is the first example of a cloned Delta5-desaturase, and differs from other fungal desaturases previously characterized by the presence of an N-terminal domain related to cytochrome b5.
School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, United Kingdom. louise.michaelson@bristol.ac.uk
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Michaelson
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Lazarus
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Griffiths
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Napier
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Stobart
D000595:Amino Acid Sequence; D016718:Arachidonic Acid / Q000096:biosynthesis; D003001:Cloning, Molecular; D004271:DNA, Fungal / Q000302:isolation & purification*; D000090943:Delta-5 Fatty Acid Desaturase; D044943:Fatty Acid Desaturases / Q000235:genetics* / Q000302:isolation & purification; D008401:Gas Chromatography-Mass Spectrometry; D008969:Molecular Sequence Data; D009090:Mucorales / Q000201:enzymology* / Q000235:genetics; D030821:Plants, Genetically Modified
D004271:DNA, Fungal; D000090943:Delta-5 Fatty Acid Desaturase; D016718:Arachidonic Acid; D044943:Fatty Acid Desaturases