Selection of brain choline acetyltransferase synthetic peptides.

Choline acetyltransferase (ChAT) of pig brain is a 640 amino acid enzyme. The sequence has recently been published (Berrard et al., 1988). We identified potentially antigenic epitopes on porcine ChAT by primary and secondary structure analysis. We used 12 structural parameters derived from the amino acid sequence, especially surface antigenicity, internal repetitions and protease cleavage site clusters and superposed gliding averages for the complete ChAT protein. Four peptides from 13 to 21 amino acids in length were defined for antibody production. In detail, we describe a nine-step selection process and discuss costs of synthesis and purification.