Phosphoglycerate kinase: an X-linked polymorphism in man

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Initiation of rabbit hemoglobin synthesis: methionine and formylmethionine at the N-terminal

Ribosome-bound peptides were prepared from rabbit reticulocytes incubated in a reaction mixture that contained all essential amino acids except tryptophan. The peptides were fractionated by Sephadex gel filtration and the N-termini of these peptides were examined. Longer uncompleted hemoglobin chains (larger than 30 amino acids) had unblocked valine at the N-terminal position. In contrast, shorter initial parts of chains (smaller than 16 amino acids) did not have valine at the N-terminal position. These small peptides had methionine at the N-terminal, and 8% of the terminal methionine was presumably formylated. These findings indicate that hemoglobin chains are initiated from methionine or N-formylmethionine (or from both methionine and N-formylmethionine), and that the methionyl residue is hydrolyzed at an early stage of chain elongation.

Single chain alkali resistance in hemoglobin Rainier: beta 145 tyrosine-histidine

The mechanism of alkali resistance in hemoglobin Rainier, an adult human hemoglobin variant (beta 145 tyrosinie --> histidinie), has been investigated. Alkali denaturation kinetics, electrophoretic and hybridization study. and ultracentrifuge analysis provided evidence for a monomeric beta Rainiier chain resisting denaturation at alkaline pH. These data provide evidence for a previously unrecognized effect of a single amino acid substitution, that is, the change of the alkali denaturation properties of monomneric chains.

A pseudocholinesterase variant (E Cynthiana) associated with elevated plasma enzyme activity

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Hemoglobin Rainier (beta145 Tyrosine rarr Histidine): Alkali-Resistant Hemoglobin with Increased Oxygen Affinity

Hemoglobin Rainier, a new hemoglobin variant associated with erythrocytosis, was found in six members of a Caucasiant family. Structurally, it represents substitution of histidine for the invariant residute H23 tyrosine in the beta-hemoglobin polypeptide chain (beta(145) tyrosine --> histidine). Hemoglobin Rainier is the first example of a single amino acid substitution in adult human hemoglobin, causing increased resistance to alkali denaturation.

Clonal origin of chronic myelocytic leukemia in man

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