Study of a kindred with hereditary spherocytosis and glyceraldehyde-3-phosphate dehydrogenase deficiency

A patient with hereditary spherocytosis (HS) was found to have glyceraldehyde-3-phosphate dehydrogenase (G3PD) deficiency by electrophoresis of the isolated red cell membranes on polyacrylamide gels with sodium dodecyl sulfate (PAGE SDS) as demonstrated by a diminished band 6 (G3PD) and confirmed by specific enzyme assay. Thirteen members of his family were studied: four were normal, two had HS alone, three had G3PD deficiency alone, and four had both HS and G3PD deficiency. G3PD deficient kindred members were probably heterozygous, since their red cell enzyme, while qualitatively normal, was present in half normal amounts. The G3PD deficiency alone was asymptomatic, and there was no evidence that the combination of HS with G3PD deficiency increased the clinical severity of the disease. However, G3PD deficiency, when combined with HS, was associated with an increase in protein band 4.5 on PAGE SDS. This band was also increased by incubation of normal red cells without glucose, and appeared to be a protein absorbed to the membrane as a consequence of metabolic stress. Hence, red cells with the combined abnormalities of both HS and G3PD deficiency showed signs of the exceptional metabolic stress to which they were exposed.

Paralimbic scleromalacia. Spontaneous scleral intercalary perforation

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The N-terminal amino acid sequence of two avian leukosis group specific antigens

Two group-specific antigenic proteins from an avian leukosis virus have been compared by amino acid analysis, tryptic peptide fingerprinting, and N-terminal sequence determination, and found to be dissimilar. There was microheterogeneity in the structure of the protein gs-b at residues 6; threonine and glutamic acid were found.

Isolation of a second avian leukosis group-specific antigen (gs-b) from avian myeloblastosis virus

Gs-b, a second group-specific antigenic protein of the avian leukosis group, has been isolated from Tween 80-ether treated avian myeloblastosis virus by Sephadex and carboxymethylcellulose chromatography, and compared by immunological and chemical means with the antigen (gs-a) described previously.