The sodium alkyl sulfates, which activate protyrosinase,1 yield polar-nonpolar anions, (RSO4). Alkylamine hydrochlorides, however, give polar-nonpolar cations (RNH3.H+), and do not activate protyrosinase.† This distinction may be of value in the search for the kind of chemical group or part of protyrosinase which is involved in its activation.Three similar preparations of protyrosinase were extracted from grasshopper eggs (Melanoplus differentialis) by a method involving trituration, fractional precipitation, and dialysis.1 Activities, measured in a Warburg apparatus, were compared by the reciprocal—multiplied by 1000—of the time in minutes for the first 100 μ1 of oxygen uptake with tyramine hydrochloride as substrate.The ascending limb of curve A (Fig. 1) shows the activation of protyrosinase that occurs in the presence of sodium dodecyl sulfate. With dodecylamine hydrochloride (Curve F, Fig. 1) there seems to be no conversion of protyrosinase into tyrosinase. When solutions of alkyl sulfates and alkylam...