Immunochemical Investigations with Highly Purified Glutamate Dehydrogenase from Pea Seeds by Means of the Ouchterlony Test

Abstract

Monospecific antibodies have been prepared with a homogeneous protein fraction of the main activity band of pea seed glutamate dehydrogenase. This protein precipitates with its antibodies in a single band with complete fusion as seen by the Ouchterlony double-diffusion test. Identical behaviour is observed with the protein of the adjacent activity bands of the multiple molecular forms of this enzyme and the antibodies to the former fraction. Organ-specific ‘isoenzymes’ of glutamate dehydrogenase with preparations of pea roots and epicotyls are not detected by this procedure. Partially purified glutamate dehydrogenase preparations from Lemna perpusilla, Zea mays, and Oryza sativa also precipitate with the antibodies to the pea protein. The Lemna protein is shown to be different from the pea enzyme as judged from immunological behaviour. The pea antibodies¹ do not cross-react with glutamate dehydrogenases from Candida or beef liver, nor do the beef liver antibodies react with the pea and Candida enzymes.