Human E apoprotein heterogeneity. Cysteine-arginine interchanges in the amino acid sequence of the apo-E isoforms.

The abbreviations used are: apo-E, E apoprotein; VLDL, very low density lipoproteins; E isoforms, E-1, E-2, E-3, and E-4, using the onedimensional gel nomenclature established by Utermann et al. (17).Equivalency of the Zannis and Breslow (20) nomenclature with the Utermann system: p-11 pattern, E-4/E-4 genotype; p-111 pattern, E-3/E-3 genotype; D-IV pattern, E-2/E-2 genotype; a-I1 pattern, E-4/E-3 genotype; a-111 pattern, E-3/E-2 genotype; a-IV pattern, E-4/E-2 genotype.and several different animals (5-10).Metabolically, this Mr ' Expressed as residues per mole, assuming Ala = 1.0 (2 determinations).Converted to homoserine and homoserine lactone, which were present in all of these hydrolysates.Determined as cysteic acid.