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Biomedical subjects

L H Ericsson

Publications and source records attributed to L H Ericsson.

67 records · Page 4Linked to original sources
PubMed1974

A comparison of bovine prothrombin, factor IX (Christmas factor), and factor X (Stuart factor).

A comparison has been made of the electrophoretic behavior, chemical composition, amino-terminal sequence, and immunological properties of bovine prothrombin, factor IX (Christmas factor), and factor X (Stuart factor). Some immunological crossreactivity was found between the antibody to prothrombin and factor X although prothrombin and factor X differ substantially in amino-acid and carbohydrate composition. Considerable amino-acid sequence homology was found in the amino-terminal portion of prothrombin, factor IX, and the light chain of factor X. These data provide further evidence to support the hypothesis that at least three of the vitamin K-dependent clotting factors have evolved from a common ancestral gene.

Amino Acid Sequence↗
PubMed1973

The function of the two subunits of thermophilic aminopeptidase I.

The thermophilic high-molecular-weight aminopeptidase I (EC 3.4.11.1) from Bacillus stearothermophilus is composed of 12 subunits of two different types (alpha,beta) which can combine in various ratios. Only one type of subunit (alpha) is needed for the degradation of neutral peptides, but dipeptides having amino-terminal aspartic or gultamic acid are substantially hydrolyzed only by enzyme containing the other subunit (beta) as well. Asp-Gly inhibits the enzymatic hydrolysis of glutamic acid 1-(4-nitroanilide) very strongly but hardly affects the hydrolysis of leucine p-nitroanilide. These results indicate that both types of subunit have hydrolytic activity but different specificity. The two subunits have identical molecular weights and their amino-terminal regions are homologous, suggesting that the two chains originate from a single ancestral gene by gene duplication and independent mutation.

Amino Acid Sequence↗
PubMed1969

The amino acid sequence of bovine carboxypeptidase A.

The amino acid sequence of the four fragments produced by treatment of bovine carboxypeptidase A with cyanogen bromide has been completed. The alignment of these fragments, previously established by peptic digest of the whole protein, allows for the description of the complete primary structure of the molecule. A comparison of the proposed functional residues, identified by X-ray diffraction analyses, has either confirmed their assignments or provided their correct identity. The functional and structural residues of principal importance include Arg 145, Tyr 248, and Glu 270 as the binding site of the substrate carboxyl group, the proton donor, and the nucleophilic moiety, respectively, which were correctly assigned; His 196 as the third zinc ligand and Tyr 265 as the binding site of the alpha-carboxyl group have been corrected from their original X-ray assignments. The other two zinc ligands, His 69 and Glu 72, were identified previously from chemical and X-ray studies. The assignment of the two half-cystinyl residues and the postulation of the existence of a disulfide bond have been confirmed.

Amino Acid Sequence↗