HETEROGENEITY OF THE HEMOGLOBIN OF THE OHRID TROUT (SALMO L TYPICUS)

We have analyzed the hemoglobins of five individual trout from the Ohrid Lake (Salmo L. typicus) by electrophoretic methods, by reversed-phase high-performance liquid chromatography, and by limited structural analyses. The two major classes of hemoglobin are type I (35% of total) and type IV (65%). Type IV is the major oxygen-transporting hemoglobin; it consists of three types of beta chain (in about equal quantities) and three types of a chain (one major and two minor types). Several structural differences have been observed between these three beta(IV) chains and between the three alpha(IV) chains, suggesting a complex genetic system governing the synthesis of these proteins. Moreover, a few amino acid substitutions occur at positions involved in contacts between chains, which suggests that differences in oxygen affinity may exist between these various type IV hemoglobins. Type I hemoglobin is less complex because it contains one type of beta chain and two a chains; the latter two differ in numerous positions, suggesting duplications of the alpha(I)-globin gene. The alpha and beta chains of type I hemoglobin differ considerably from the alpha and beta chains of type IV hemoglobin, indicating the existence of alpha(I)- and beta(I)-globin genes separate from the alpha(IV)- and beta(IV)-globin genes.