Primary sequence of the β-chain of badger haemoglobin

• Published in: Biochimica et biophysica acta Vol. 427; no. 1; pp. 107 - 118
• Main Authors: Hombrados, Isabelle, Ducastaing, Simone, Iron, Albert, Neuzil, Eugene, Debuire, Brigitte, Han, Kia-Ki
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 18.03.1976
• Subjects: Amino Acid Sequence; Amino Acids - analysis; Animals; Carnivora; Hemoglobins; Humans; Peptide Fragments - analysis; Species Specificity; Trypsin; Dns-dansyl; Tos Phe CH 2Cl; Ptc
• ISSN: 0005-2795; 0006-3002; 1879-2952
• DOI: 10.1016/0005-2795(76)90289-0

Badger ( Meles meles) haemoglobin was purified by paper electrophoresis and converted into globin. Chain separation was carried out on a CM-cellulose column in the presence of 8 M urea. The β-chain was aminoethylated, purified by gel filtration and submitted to tryptic digestion. A fingerprint obtained with the enzymic digests showed 17 distinct ninhydrin-positive spots from which 20 pure peptides were isolated by further electrochromatographic separations. These peptides were sequenced using Dansyl-Edman and Ptc-Edman degradation techniques. The presence of amide residues was confirmed after aminopeptidase M hydrolysis. Taking human haemoglobin β-chain as a model, the covalent structure could be completely resolved without the help of any further overlapping technique. The following substitutions were noted (badger/human, position): Ala/Pro 5, Ser/Ala 13, Tyr/Phe 41, Asp/Glu 43, Ser/Ala 70, Glu/Asp 73, Lys/Ala 76, Asn/His 77, Lys/Thr 87, Lys/Arg 104 and Gln/Pro 125. A comparison with other haemoglobin β-chains already sequenced shows a greater similarity with dog haemoglobin, the only example of β-chain of known structure in the order of Carnivores.