Joan B. Shelton

High Performance Liquid Cbromatographic Separation of Globin Chains on a Large-Pore C4 Column

Abstract Excellent resolution of human and baboon globin chains may be obtained by HPLC on a Vydac large-pore C4 column. The procedure is rapid and uses a gradient between aqueous trifluoroacetic acid and trifluoroacetic acid in acetonitrile. The common human γ chains are easily separable from each other as are some α- and β-chain variants from the normal chains and from each other.

An examination of conditions for the cleavage of polypeptide chains with cyanogen bromide: Application to catalase

Abstract The poor cleavage of a -Met-Thr- bond in catalase by cyanogen bromide has been improved by modifying the conditions of the reaction. More complete cleavage occurs in 70% trifluoroacetic acid than in 70% formic acid. The much slower rate of reaction in trifluoroacetic acid has been enhanced by increasing the concentration of the reactants.

THE PRESENT STATUS OF THE HETEROGENEITY OF FETAL HEMOGLOBIN IN β‐THALASSEMIA: AN ATTEMPT TO UNIFY SOME OBSERVATIONS IN THALASSEMIA AND RELATED CONDITIONS*

t Laboratory o f Protein Chemistry, Department of Cell and Molecular Biology, Medical College of Georgia and Veterans Administration Hospital Augusta, Georgia 30902

The complete amino acid sequence of bovine liver catalase and the partial sequence of bovine erythrocyte catalase.

Division of Chetnistry and Chemical Engineering,

Postnatal Changes in the Chemical Heterogeneity of Human Fetal Hemoglobin

California Institute of Technology Pasadena, California 91 109 5 Department of Physiology and Biochemistry, Faculty o f Agriculture Department of Pediatrics, Faculty of Medicine University of Skopje Skopje, Yugoslavia Childrens Hospital of Los Angeles and Department of Pediatrics School of Medicine, University of Southern California Los Angeles. California 90027 * * Department of Hematology, Hadassah Medical School Hadassah University Hospital, Hebrew University Jerusalem, Israel

Separation of peptides by high-pressure liquid chromatography for the identification of a hemoglobin variant.

Abstract The data upon which the sequence of the 506 residues in the subunit of bovine liver catalase (BLC) is based are presented in detail. A partial sequence of bovine erythrocyte catalase (BEC) which accounts for 493 residues shows complete concordance with the BLC data. On the other hand, BEC has at least 517 residues, that is, an extension beyond the C terminus of the BLC data. Although normally BLC has only 506 residues, there is evidence that, at some point in its history, it also had the C-terminal extension. It is speculated that this extension is lost in BLC either through a different processing of the molecule in liver than in erythrocytes or by partial degradation in the first stages of catabolism.

Further studies of the frequency and significance of the Tgamma-chain of human fetal hemoglobin.

Abstract The sequences of amino acids in the β-chains of adult bovine hemoglobins A and B have been partially determined and compared. Three differences in sequence are apparent at residues 15, 18, and 119 of the 145-residue chains. There is no evidence of other variation, although this has not been determined with certainty. In an earlier investigation, it was concluded that the α-chains of the two hemoglobins are probably identical in sequence. The multiple differences between these two chains are in contrast to the single difference between most human hemoglobin variants. The relationship between the two bovine hemoglobins is reminiscent of that between human hemoglobins A and A2 or CHarlem, as well as between sheep hemoglobins A and B. The implications of these relationships are discussed.

Nature of fetal hemoglobin in the Greek type of hereditary persistence of fetal hemoglobin with and without concurrent beta-thalassemia.

Extract: The fetal hemoglobin (Hb-F) of blood samples from 11 newborn babies (two normal infants, two sickle cell trait carriers, two Hb-C heterozygotes, two infants with Hb-SG disease, one infant with Hb-Richmond heterozygosity, one β-thalassemia heterozy-gote, and one infant with a heterozygosity for the hereditary persistence of fetal hemoglobin) and from 16 adults (eight normals, two Hb-S heterozygotes, one Hb-C heterozygote, and five SC patients) has been examined to determine the ratio of the two structurally different γ chains, namely the Gγ and Aγ chains. This ratio is about 2:3 in the Hb-F of the adults and, therefore, significantly different from the 3:1 ratio in the Hb-F of the newborn. This newborn ratio undergoes a considerable change between the 3rd and 4th months of life, at which time it approaches that of the Hb-F of adults.Speculation: The mechanism by which the gradual change from γ chain synthesis to β and δ chain synthesis is controlled remains unclear. However, the change in the ratio of production of structurally different γ chains as a function of postnatal age indicates a rather complex mechanism which probably involves an unequal repression of the γ chain structural genes. Any explanation of the mechanism must take into account the fact that the production of two genes, the Gγ and Aγ, is greatly decreased, whereas that of two other genes, the β and δ, is started. Perhaps a closely related or even identical mechanism controls not only the ratio of production of the Gγ and Aγ genes but also that of the β and δ genes.

Amino acid sequence of the α-chain of bovine fetal hemoglobin☆

High-pressure liquid chromatography on a reversed-phase column has been used to separate the tryptic peptides of a human hemoglobin variant which was then identified as hemoglobin E.