ARS | Publication request: PATHWAYS FOR FATTY ACID ELONGATION AND DESATURATION IN NEUROSPORA CRASSA

Submitted to: Lipids Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 29, 1996
Publication Date: N/A

Interpretive Summary: Vegetable oils have food and industrial uses that are dependent on fatty acid composition. Oilseeds can be genetically altered to optimize the fatty acid content for specific uses, but the genes that control vegetable oil composition must be isolated first. These genes may be isolated by expression in certain microbes, such as Neurospora crassa, that make the same fatty acids that are present in vegetable oils. This paper describes important aspects of fatty acid biosynthesis in N. crassa that will help us to identify plant genes that control the level of important fatty acids. The ultimate benefit of this research will be a way to modify vegetable oil composition to improve crop profitability and provide renewable resources that serve as an industrial feedstock.

Technical Abstract: Neurospora crassa readily incorporates exogenous fatty acids (FA) from its culture medium, facilitating studies of FA metabolism. The metabolic fate of two of the major FA of Neurospora was followed by feeding labelled exogenous palmitate (16:0) or oleate (18:1D9). Both FA were incorporated into cell lipids, and were partially converted to other FA. However, while exogenous 18:1D9 was further desaturated to 18:2D9,12 and 18:3D9,12,15, exogenous 16:0 was excluded from the major N. crassa desaturation pathway. The fact that free 16:0 is committed to saturated FA synthesis suggests 16:0 release from FA synthetase is a key control point that can determine the FA composition in Neurospora.