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Biomedical subjects

M Heidelberger

Publications and source records attributed to M Heidelberger.

At least 37 records · Page 2Linked to original sources
PubMed1975

Glycoproteins secreted by sublingual glands of the echidna (Tachyglossus aculeatus).

The portion of echnida sublingual glycoproteins which could be solubilized was fractionated by electrophoresis in polyacrylamide gel and by filtration on a column of Sephadex G-100. Analyses for carbohydrate and amino acid are given and are compared with those of the submaxillary mucins of cattle, dog, pig and sheep. The molar ratio of galactosamine to sialic acid was roughly 1:1 in the echidna fractions, the sialic acid was N-acetyl-neuraminic acid, and there was very little neutral sugar. Proline was relatively high in amount, and isoleucine, half-cystine, methionine, leucine, tyrosine, and phenylalanine were absent or present to a very small extent. The material was weakly antigenic in the rabbit.

Amino Acids↗
PubMed1972

Immunochemical studies on the capsular polysaccharide of pneumococcal type IX.

1. In addition to the previously identified components, d-glucose, N-acetyl-d-glucosamine and d-glucuronic acid, the immunologically specific capsular polysaccharide of pneumococcal type IX (polysaccharide S IX) is now found to contain mannosamine and galactosamine, probably as their N-acetyl derivatives. 2. Partial hydrolysis yields a complex mixture of oligosaccharides, several of which have been separated. 3. One of these is alpha-d-glucuronopyranosyl-(1-->3)-d-glucose. It is an inhibitor of the precipitation of antipneumococcal type IX serum by polysaccharide S IX. 4. Two others, d-glucuronopyranosyl-(1-->3)-d-glucosamine and d-glucuronopyranosyl-(1-->3)-d-galactosamine have been identified and a trisaccharide and pentasaccharide partially characterized.

Chromatography, Ion Exchange↗
PubMed1972

Oxidation of the capsular polysaccharide of pneumococcal type IX by periodate.

1. The pneumococcal type IX polysaccharide (polysaccharide S IX) has been oxidized by sodium metaperiodate and reduced by sodium borohydride. Of the constituent monosaccharides, N-acetylglucosamine and N-acetylmannosamine remain unaltered, whereas 40% of the glucose and 90% of the glucuronic acid are oxidized. 2. The effect of oxidation and subsequent reduction on the precipitation of polysaccharide S IX in anti-(pneumococcal) sera is described and interpreted in structural terms. 3. Oligosaccharides produced by oxidation, reduction and hydrolysis with dilute acid have been isolated and partially characterized. 4. The results in this paper and the preceding one (Higginbotham et al., 1972) are used to postulate a possible structure for polysaccharide S IX.

Borohydrides↗
PubMed1970

Degradation of a pneumococcal type-specific polysaccharide with exposure of group-specificity.

Pyruvic acid is an immunological determinant of the quite rigorously type-specific capsular polysaccharide of pneumococcal type IV (S IV). Removal of pyruvic acid by mild hydrolysis converts the capsular polysaccharide of type IV into an analog of the pneumococcal group-specific C-substance. Depyruvylated S IV resembles C-substance so closely immunologically that it not only precipitates a high proportion of the anti-C in antipneumococcal sera, regardless of their immunological types, but also, like C, precipitates human C-reactive protein in the presence of calcium ions. Apparently, the removal of pyruvic acid ketal rings from adjacent sugars unmasks N-acetylgalactosamine residues which must be linked and spaced much as are those in C-substance. Groupings reactive with suitably linked N-acetylgalactosamine, therefore, appear to be located on the surfaces of molecules of human C-reactive protein.

Antigen-Antibody Reactions↗
PubMed1969

Immunochemistry of newly found substituents of polysaccharides of Rhizobium species.

Acetyl and pyruvic acid groups were detected and estimated in the extracellular polysaccharides of Rhizobium trifolii and R. meliloti. Pyruvic acid was found also in the specific polysaccharide of pneumococcal type 27, and is believed to explain the cross-reactivity between antiserum to pneumococcal type 27 and these and other pyruvate-containing bacterial polysaccharides. Removal of pyruvate from a Rhizobium polysaccharide rendered it inactive with its homologous antiserum and with antiserum to pneumococcal type 27, but it then reacted with several antiserums to other pneumococcal types with which the intact material was unreactive.

Acetates↗