Genetic studies on plasma esterase isozymes in chicken

By starch-gel electrophoresis, the chicken blood plasma was examined and genetically controlled variants of α-naphthyl butyrate esterases were detected.The buffer system used was a modification of POULIK (LUSH, 1961) in which the gel buffer (pH, 8.65) contained 0.076M citric acid, and the electrode buffer (pH, 8.81) contained 0.3M boric acid and 0.1M NaOH. Electrophoresis was carried out horizontally for three hours at 10°C with a potential gradient of 250 volts across the gel (0.5×12.0 ×20.5cm). After the electrophoresis, the starch gel was sliced horizontally into halves and each half was stained for esterases in the following mixture which was prepared immediately before use by the method of PETRAS (1963):Fast blue RR salt 50mg.0.1M, pH 6.8 Phosphate buffer 16ml.1% Acetone soln. of α-naphthyl butyrate 2ml.Distilled water 180ml.In the fastest migrating region, tentatively designated ES-1 bands was intensely stained, and in this region the three phenotypes, ES-1F, ES-1FS, and ES-1S, were observed in both sexes. The mobility of ES-1F was greater than ES-1S. ES-1FS contained the two bands, ES-1F and ES-1S.From mating results, it is proposed that these phenotypes were controlled by a pair of the autosomal codominant alleles, ES-1F and ES-1S.The region was inhibited by Tri-cresyl phosphate and Parathion, whereas it was resistant to eserine. Both aliphatic and aromatic esters were hydrolyzed by the esterases, suggesting these esterases are aliesterases.