PURIFICATION AND PROPERTIES OF THE HEMOGLOBINS OF THE PLATYHELMINTH ISOPARORCHIS-HYPSELOBAGRI (TREMATODA, ISOPARORCHIDAE) AND ITS HOST WALLAGU-ATTU (CATFISH)

1. The hemoglobins of the trematode Isoparorchis hypselobagri and of i ts host Wallagu attu (catfish) were isolated and purified. 2. SDS-poly acrylamide gel electrophoresis showed both to consist of single, 15-17 kDa chains, having different electrophoretic mobilities. 3. Isoelectr ic focusing showed the trematode hemoglobin to be homogeneous with a p I of 4.2 and the host hemoglobin to consist of several components. 4. Gel filtration of freshly prepared trematode hemoglobin revealed one p eak corresponding to M(r) approximately 17 kDa; gel filtration of a pr eparation which had been stored for 2-3 months demonstrated the presen ce of two peaks, whose elution volumes corresponded to M(r) of ca 35 a nd 17 kDa, respectively. 5. Reversed-phase chromatography of carboxyme thylated 35 and 17 kDa peaks on a C-8 column, gave a single peak a and two peaks b and c, respectively. 6. Edman degradation of peaks a, h a nd c obtained provided identical sequences of 27 amino acid residues f or peaks a and c and another sequence differing at 10 of the 27 positi ons, for peak b. Edman degradation of the freshly prepared Isoparorchi s hemoglobin provided the first 15 amino acid residues found for peaks a and c. The host hemoglobin gave an N-terminal sequence completely d ifferent from the trematode sequences. 7. Since gel filtration of the 35 and 17 kDa peaks showed no sign of an interconversion equilibrium, it appears that the 35 kDa peak and peak a represent a disulfide-bonde d dimer of a monomer globin chain which shares the 27 N-terminal resid ues with chain c, the major monomer globin component of the 17 kDa pea k. 8. The hemoglobin of L hypselobagri consists of at least three diff erent, monomeric globin chains, with one of the chains exhibiting a ti me-dependent formation of disulfide-bonded dimers.