Comparison of the incorporation of oleate and ricinoleate into phosphatidylcholines and acylglycerols in soybean microsomes.
The incorporations of oleate (endogenous) and ricinoleate (nonendogenous) into phosphatidylcholine (PC) and acylglycerol (AG) in immature soybean microsomes were compared. [(14)C]Oleate and [(14)C]ricinoleate were incubated individually with soybean microsomal preparations for up to 4 h, and molecular species of PC and AG incorporated were identified and quantified by HPLC. The activities of acyl CoA:lysoPC acyltransferase and phospholipase A(2) are in general not affected by the fatty acid (FA) chain at the sn-1 position. However, comparison between oleate and ricinoleate revealed that different FA incorporated at sn-2 of PC showed some different selection of the molecular species of lysoPC. The incorporation of [(14)C]ricinoleate into triacylglycerols (TAG) was slightly better than that of [(14)C]oleate and indicated that soybean was capable of incorporating ricinoleate into TAG when ricinoleate can be produced endogenously in a transgenic soybean. The incorporation of FA into TAG in soybean microsomes was much slower than that in castor microsomes.
Western Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, 800 Buchanan Street, Albany, California 94710, USA. jtlin@pw.usda.gov
Jiann-Tsyh
JT
Lin
Marc D
MD
Ikeda
Thomas A
TA
McKeon
D002250:Carbon Radioisotopes; D002851:Chromatography, High Pressure Liquid; D005989:Glycerides / Q000378:metabolism*; D008861:Microsomes / Q000378:metabolism*; D019301:Oleic Acid / Q000378:metabolism*; D010713:Phosphatidylcholines / Q000378:metabolism*; D012277:Ricinoleic Acids / Q000378:metabolism*; D013025:Glycine max / Q000648:ultrastructure*; D014280:Triglycerides / Q000378:metabolism
D002250:Carbon Radioisotopes; D005989:Glycerides; D010713:Phosphatidylcholines; D012277:Ricinoleic Acids; D014280:Triglycerides; D019301:Oleic Acid; C030521:ricinoleic acid