[Hemoglobins XLVI: the primary structure of the alpha-chain of armadillo (Dasypus novemcinctus, Edentata) hemoglobin (author's transl)].

The complete primary structure of the identical alpha-chains of the two hemoglobin components of armadillo (Dasypus novemcinctus) is presented. It was established on the tryptic peptides by automatic Edman degradation. The alignment was done according to the homology with human alpha-chains. 25 differences were found between both chains. A comparison of the functional amino acid residues shows one substitution in the surrounding of the heme, there in the alpha 1 beta 1 - and two in the alpha 1 beta 2 - subunit interface. The two replacements alpha 38(C3)Thr leads to Pro and alpha 44(CD) - Pro leads to Ser may contribute to the high oxygen affinity of the armadillo hemoglobin by destabilization of the T-structure.