Cross-reactivity of an antibody to spiny lobster P450 2l with microsomes from other species

The gene for a new form of P450, CYP2L, was recently sequenced in this laboratory, using a primer designed from the N-terminal amino acid sequence of a P450 partially purified from spiny lobster hepatopancreas microsomes. The partially purified (75% pure) P450 was used to immunize rabbits. Serum containing the rabbit anti-CYP2L antibody was demonstrated to possess good cross-reactivity on Western blots with microsomal preparations from hepatopancreas of the spiny lobster. In Western blot studies with microsomal preparations from other aquatic invertebrates, the horseshoe crab, the blue crab, the slipper lobster, the American lobster and the brown shrimp, the slipper lobster microsomal preparations showed strong cross-reactivity with the spiny lobster antibody and the American lobster weak cross-reactivity. Hepatic microsomes from all of the vertebrate species studied showed cross-reactivity with the anti-CYP2L antibody. The fish species studied were killifish, clear-nose skate, snook and catfish. Strong cross-reactivity was found with killifish and catfish, and weak cross-reactivity was found with skate and snook in the 45–66 kDa region. Cross-reactivity was also found with microsomes from male control and phenobarbital-induced rats. These studies suggest that epitopes in CYP2L are also present in other invertebrate and vertebrate species.