Arginine phosphate in compound eyes

Summary The steady state levels of various phosphate esters were measured in the compound eyes of two species of decapod crustaceans (Astacus andEupagurus) and of the blowfly (Calliphora). In the crustaceans, free nucleotides—especially ATP—contribute only little to the soluble phosphate fraction. The adenylate charges of all three species are in the range of about 0.8, though the proportion of adenine nucleotides to other organic phosphates differs considerably. The main energy rich phosphate compound in crustacean eyes was found to be arginine phosphate; the ratio ATP/Arg-P is 1:10 inAstacus, and 1:4 inEupagurus; in the blowfly it is near 1:1. Arg-P is considered to play a role as a phosphagen.This investigation was supported by Deutsche Forschungsgemeinschaft, Sonderforschungsbereich 114 (Bionach)