Molecular properties of lupin and serradella leghaemoglobins

1. Leghaemoglobins were extracted from the root nodules of lupin (Lupinus luteus L.) and serradella (Ornithopus sativus Brot.) plants and fractionated into different leghaemoglobin components on DEAE-cellulose-acetate columns. 2. The first two fractions eluted from columns loaded with either lupin or serradella leghaemoglobins were in the Fe(3+) oxidation state. 3. These components have protohaem IX as the prosthetic group and glycine as the N-terminal amino acid. 4. Other properties are: lupin component I, pI5.08, molecular weight 19000; lupin component II, pI5.13, molecular weight 20600; serradella component I, pI5.00, molecular weight 17500; serradella component II, pI5.05, molecular weight 19100. 5. Leghaemoglobins are thus heterogeneous with respect to size and charge.