Structural Adaptation of Bird Hemoglobins to High-Altitude Respiration and the Primary Sequences of Black-Headed Gull(Larus ridibundus,Charadriiformes) αA- and β/β´-Chains

Publisher Website
Google Scholar
Abstract
Two hemoglobin components HbA (.alpha.2A.beta.2) and (.alpha.D2.beta.2) have been detected by analytical electrophoresis in the lysed erythrocytes of the adult Black-Headed Gull (Larus ridibundus). We report the complete primary structure of the .alpha.A- and .beta.-chains of the major hemoglobin component HbA. Following the chain separation and isolation of the tryptic peptides by RP-HPLV, the amino-acid sequence was established by automatic Edman degradation in spinning cup and gas-phase sequencers. The primary structures of .alpha.A- and .beta.-chains from the Black-Headed Gull HbA differ by 11 and by 6 amino-acid residues from the corresponding chains of Greylag Goose. These changes are randomly distributed over both .alpha.-helical and interhelical regions. The presence of .beta./.beta.''-chains is indicated by the observation of Ile/Leu at position .beta.78. An exchange at position .beta.55(D6)Leu-Asn which is known to be involved in the .alpha.1.beta.1-interface with .alpha.119(H2)Pro has been found. It is suggested that packing contacts in the .alpha.1.beta.1-interface are important for high altitude respiration in birds.

This publication has 34 references indexed in Scilit: