The globin composition of Daphia pulex hemoglobin and the comparison of the amino acid composition of invertebrate hemoglobins

Abstract

1. 1. A method was established for the purification to homogeneity of Daphnia pulex and other small sized invertebrate hemoglobins.

2. 2. The purified hemoglobin has an apparent Mr of 420,000–460,000 and a S(20, w) of 17.05.

3. 3. Four globin chains α, β1, β2 and γ with Mr between 32,000 and 35,000 were identified. The α- and β-chains are involved in the formation of disulfide linked dimers (α-α, α-β, β-β). The native molecule is constructed of 12 globin chains.

4. 4. The α-globin chain was purified to homogeneity.

5. 5. The globin chains were separated by preparative PAGE and their amino acid composition determined.

6. 6. The amino acid composition of 140 invertebrate hemoglobins is collected and it is shown that their comparison can be used to establish structural and taxonomical relationships.