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I Katnik

Publications and source records attributed to I Katnik.

23 records · Page 2Linked to original sources
PubMed1984

Immunological comparison of glycopeptides obtained from haptoglobin types 1-1, 2-1 and 2-2.

Immunochemical properties of glycopeptides III and IV obtained from haptoglobin (Hp) types 1-1, 2-1, and 2-2, by trypsin digestion were studied by double immunodiffusion test, quantitative precipitation and crossed immunoelectrophoresis with antisera directed against Hp 1-1, Hp 2-1, and Hp 2-2, respectively. Trypsin digestion resulted in an exposition in the glycopeptide IV 1-1 of the antigenic determinant characteristic of Hp 1-1, which had been hidden inside the molecule of the native Hp 1-1. On the contrary, it was not possible to find an antigenic determinant characteristic of the product of alpha 2 gene.

Cross Reactions↗
PubMed1981

The effects of limited proteolysis by trypsin on human haptoglobin.

Trypsin digestion of haptoglobin resulted i four glycopeptides. The glycopeptides were characterized by amino acid composition and molecular weight, as determined by thin-layer chromatography, and sodium dodecyl sulphate-polyacrylamide gel electrophoresis in the presence or absence of 2-mercaptoethanol. Hemoglobin-binding capacity and immunological properties were investigated. glycopeptides I and II did not form an active complex with hemoglobin and they inhibited the reaction of haptoglobin with specific antiserum by over 70%. Glycopeptides III and IV showed 11 and 4% of the hemoglobin-binding capacity and 82 and 67% of antigenic reactivity of native haptoglobin, respectively. Glycopeptide IV contained three antigenic determinants, whereas glycopeptides III contained four, one of them being exposed by trypsin digestion. In crossed two-dimensional immunoelectrophoresis, glycopeptide III showed at least four components reacting with antihaptoglobin serum, and glycopeptide IV, two components.

Amino Acids↗
PubMed1977

Influence of modifications of physicochemical and biological properties of haptoglobin. VII. Immunochemical reactivity of haptoglobin with modified tyrosine residues.

Tyrosine residues in human haptoglobin (Hp) type 2-1 were modified by treatment with various amounts of N-acetylimidazole, iodine or tetranitromethane. Rabbit antisera directed against native Hp, Ac-Hp, 1-Hp and NO2-Hp in cross-reactions by immunoprecipitation showed serologic identify of native Hp and most of the modified derivatives, with the exception of derivatives modified by means of a high excess of N-acetylimidazole, which showed partial identity with remaining preparations, irrespective of the antiserum used. The results indicate that tyrosine residues play no essential role in the immunochemical reactivity of haptoglobin.

Acetylation↗