Enzymatic and immunological comparison of alanine: glyoxylate aminotransferases from different fish and mammalian livers.

Alanine:glyoxylate aminotransferase was highly purified and characterized from mackerel liver. The purified enzyme had a mol. wt of approx. 200,000 with four identical subunits. It was specific for L-alanine and L-serine with glyoxylate and for L-serine with pyruvate as amino acceptor. The mackerel enzyme was similar to partially purified alanine:glyoxylate aminotransferases from other fish (sardine, gopher gray rock cod and yellow mackerel) liver with respect to mol. wts and substrate specificity. These fish enzymes were similar to mammalian liver alanine:glyoxylate aminotransferases 1 in substrate specificity and to mammalian alanine:glyoxylate aminotransferases 2 in mol. wts. An immunological cross-reactivity of hepatic alanine:glyoxylate aminotransferase was observed between mackerel and other fishes but not between mackerel and mammals.