Pathways for fatty acid elongation and desaturation in Neurospora crassa.
Neurospora crassa incorporated exogenous deuterated palmitate (16:0) and 14C-labeled oleate (18:1 delta 9) into cell lipids. Of the exogenous 18:1 delta 9 incorporated, 59% was desaturated to 18:2 delta 9,12 and 18:3 delta 9,12,15. Of the exogenous 16:0 incorporated, 20% was elongated to 18:0, while 37% was elongated and desaturated into 18:1 delta 9, 18:2 delta 9,12, and 18:3 delta 9,12,15. The mass of unsaturated fatty acids in phospholipid and triacylglycerol is 12 times greater than the mass of 18:0. Deuterium label incorporation in unsaturated fatty acids is only twofold greater than in 18:0, indicating a sixfold preferential use of 16:0 for saturated fatty acid synthesis. These results indicate that the release of 16:0 from fatty acid synthase is a key control point that influences fatty acid composition in Neurospora.
McKeon
T A
TA
USDA, ARS, Western Regional Research Center, Albany, California 94710, USA.
Goodrich-Tanrikulu
M
M
Lin
J T
JT
Stafford
A
A
D003903:Deuterium / Q000378:metabolism; D005227:Fatty Acids / Q000096:biosynthesis / Q000378:metabolism*; D005231:Fatty Acids, Unsaturated / Q000378:metabolism; D050356:Lipid Metabolism; D008055:Lipids / Q000737:chemistry; D013058:Mass Spectrometry; D009492:Neurospora crassa / Q000378:metabolism*; D019301:Oleic Acid / Q000378:metabolism*; D019308:Palmitic Acid / Q000378:metabolism*; D010743:Phospholipids / Q000737:chemistry / Q000378:metabolism; D014280:Triglycerides / Q000737:chemistry / Q000378:metabolism
D005227:Fatty Acids; D005231:Fatty Acids, Unsaturated; D008055:Lipids; D010743:Phospholipids; D014280:Triglycerides; D019301:Oleic Acid; D019308:Palmitic Acid; D003903:Deuterium