Immunochemical characterization of the multimolecular forms of squid ink gland tyrosinase

Tyrosinase extracts were prepared from squid ink glands, Hardy-Passey mouse melanoma and human melanoma, and rabbit anti-squid tyrosinase serum was raised. Immunodiffusion and immuno-electrophoresis were carried out and the presence of specific tyrosinase antibody complexes detected. The antiserum reacted only with squid tyrosinase, the latter retaining its enzymic activity, which is therefore dependent on a site other than the immuno-chemically reacting one. Two forms of the enzyme were evident from immunodiffusion, 3 from immuno-electrophoresis. Two of the latter were immunochemically similar and probably contain similar antigenic groups, but their relationship with the other form cannot be determined with these techniques and will be investigated.