β Scribed by R. J. Henderson; J. R. Sargent
No coin nor oath required. For personal study only.
A comparison was made of neutral lipid biosynthesis by intact Euchaeta norvegica, gut tissue isolated from E. norvegica and the E. norvegica from which the gut tissue had been removed. Incorporation of radioactive glucose and alanine into triacylglycerols by all three systems exceeded that into wax esters. Whereas 86.7% of the glucose incorporated into triacylglycerols by gut tissue was located in the glycerol moiety, only 21.8 and 23.8% of glucose incorporated into triacylglycerols by intact and disembowelled copepods, respectively, was recovered in the glycerol moiety. Incorporated alanine in triacylglycerols was always located preferentially in the fatty acid moiety. Radioactive hexadecanol was always extensively incorporated into wax esters, with internal tissues being much more active than gut tissue. The major portion of glucose and alanine incorporated into wax esters was in the fatty alcohol moiety. Gut tissue was much more active than internal tissues in oxidising hexadecanol to hexadecanoic acid. We conclude that gut tissue synthesises glycerol 3-phosphate for use in the esterification of dietary fatty acids to form triacylglycerols. Gut tissue is also active in oxidising dietary fatty alcohols. Fatty acid biosynthesis, leading to wax ester formation, is a property of internal tissues rather than of the gut.
π SIMILAR VOLUMES
Preparations of Euchaeta norvegica eatalyse the incorporation of (1-14C) hexadecanol, (9,10-~H~) oleie acid, (U-I~C) glucose, (U-I~C) alanine and (U-I~C) aspartie acid into wax esters. Both the fatty alcohol and fatty acid moieties of the wax esters are labelled, indicating de novo biosynthesis. A l