Fatty acid metabolism in the calanoid copepod Paracalanus parvus: 1. Polyunsaturated fatty acids

The metabolic fate of radioactive linoleate and alpha-linolenate administered to the South Atlantic copepod Paracalanus parvus was studied. The wild copepod was able to incorporate the labeled acids dissolved in seawater. The radioactive linoleate was elongated to 20:2omega6 and 22:2omega6 and desaturated by a delta6 desaturase to 18:3omega6. alpha-Linolenate was also desaturated by a delta6 desaturase to 18:4omega3 and elongated to 20:3omega3. The copepod was able to convert alpha-18:3 to 20:5omega3 and 22:6omega3.