W. A. Schroeder

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.

Human erythrocyte catalase: an improved method of isolation and a reevaluation of reported properties.

An improved method for the isolation of human erythrocyte catalase from large volumes of cells is described. Time of isolation has been reduced and the need for larger equipment has been minimized. The yield is 200–300 mg per liter of packed cells. Amino acid composition, molecular weight, spectral constants, heme content, activity, and N-terminal residues have been determined. Although the isolative procedure is a modification of that of Morikofer-Zwez et al. (1969) (Eur. J. Biochem.11:49), the lability of the product toward oxygen as reported by them has not been observed nor has it been possible to produce extensive changes in properties of the material by subjecting it to the adverse conditions that they describe. However, by chromatographic procedures, it has been shown that the catalase immediately after isolation has a heterogeneity different than they describe and that alteration with time does occur. The cause of the heterogeneity has not been determined.

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

A reinvestigation of the hydrazinolytic procedure for the determination of C-terminal amino acids

Division of Chetnistry and Chemical Engineering,

A comparison of amino acid sequences in the β-chains of adult bovine hemoglobins A and B

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

Lack of influence of fetal hemoglobin levels or erythrocyte indices on the severity of sickle cell anemia.

Abstract This reinvestigation of the hydrazinolytic procedure for C-terminal amino acids has resulted in an improved procedure for isolating and determining the released amino acid and in altered conditions of hydrazinolysis that improve the yield. The method of determination uses isolation by ion-exchange chromatography with volatile developers and subsequent automatic amino acid analysis. The addition of Amberlite CG-50 to the hydrazinolytic mixture has increased the yield of C-terminal amino acids. Upon application to ten proteins with known C-terminal amino acids, five have given uncorrected yields of 90–100% of the theoretical; in only one instance did the yield fall below 64%.

Postnatal Changes in the Chemical Heterogeneity of Human Fetal Hemoglobin

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.

βS-gene-cluster haplotypes in sickle cell anemia : clinical implications

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.