The Primary Sequence of the β Chain of Hb Type Iii of the Virginia White-Tailed Deer (Odocoilus Virginianus), a Comparison with Putative Sequences of the β Chains from Four Additional Deer Hemoglobins, Types Ii, Iv, V, and Vii, and Relationships Between Intermolecular Contacts, Primary Sequence and Sickling of Deer Hemoglobins

Abstract

The amino acid sequence of the β^III chain of the hemoglobin type III present in a Virginia white-tailed deer, Odocoilus Virginianus, was determined by automatic sequencing of the intact chain, of three large fragments, and of two tryptic peptides. Analyses of the β chains of type III Hb's collected from four additional animals have uncovered individually occurring silent mutations at positions 72 or 125 or 144. The more limited data on the β chain of Hb type II suggest 8 structural differences between the β^II and β^III chains which are located at positions 56, 66, 69, 70, 87, 135, 143, and 144. The β chain of Hb type IV likely is a variant of the β^II chain in which lysyl residue in position 87 is replaced by a glutaminyl residue. The “non-sickling” hemoglobins V and VII have closely related 6 chains which differ considerably in their structures from the β chains of “sickling” Hb types II, III and IV. Marked variation is present in the amino terminus while at least five isoleucyl residues are present in the β^V chain as well as in the β^VII chain. The great variability in Hb phenotype in the Virginia white-tailed deer is widespread among members of this species as is evident from results of surveys conducted in ten southeastern states during the past 15 years. The critical intermolecular contact regions in cyanomet deer Hb type III which give rise to the antiparallel double strands in the crystal can be related to the amino acid differences and the sickling of Hb type III, and nonsickling of the Hb types V, VII.