"Leucine aminopeptidase" (neutral arylamidase) in sheep sera: improved resolution with gradient gel electrophoresis.

Electrophoretic resolution of the heterogeneity of sheep serum "leucine aminopeptidase" is greatly improved by the use of gradients of acrylamide polymer, together with enzyme localisation involving L-alanyl beta-naphthylamide and cobaltous ion. The improved resolution contradicts an earlier claim of the existence of only two patterns of individual variation in the heterogeneity of sheep serum "leucine aminopeptidase", with one pattern completely dominant to the other. While the sheep enzyme is unusual among mammalian serum "leucine aminopeptidases" in its complex heterogeneity, it does conform to the typical mammalian pattern of codominant individual variation. The complexity of sheep serum "leucine aminopeptidase" is useful in the study of sheep evolution.