The hemolymph proteins of the blue crab, callinectes sapidus—I. Hemocyanins and certain other major protein constituents

Abstract

1. 1. Starch-gel electrophoresis revealed considerable qualitative and quantitative variation in the proteins of hemolymph samples from individual adult specimens of Callinectes sapidus. 2. 2. Partial separation of the hemolymoh proteins was achieved by continuous-flow paper curtain electrophoresis. 3. 3. Two hemocyanins, fast and slow, are not interconvertible. 4. 4. Removal of copper from isolated hemocyanins by dialysis against cyanide-containing buffers produced apohemocyanins with electrophoretic mobilities identical to those of the intact hemocyanins. 5. 5. Fast hemocyanin has a copper-protein ratio of 0·2:100 and dissociates at alkaline pH. 6. 6. Slow hemocyanin is found almost exclusively in hemolymph from females. 7. 7. Another female-limited protein is found only in those specimens with maturing oocytes; this yellow, high-density lipoprotein is apparently associated with vitellogenesis. 8. 8. A “complex” protein, extremely variable in quantity, binds 59Fe and possesses amylase activity. 9. 9. A clotting protein is more abundant in serum than in plasma from the same animal. 10. 10. Species specificity of the electrophoretic patterns is confined to the characteristic mobility and dissociation of fast hemocyanin, the only protein found to be present in all samples of blue crab hemolymph.