Étude chimique de la mucoprotéine responsable du phénomène d'obstacle de donaggio

Abstract

The glycoprotein extracted from the urine of cancerous patients is shown by electrophoresis to be a mixture of substances; the active fraction can be isolated in a pure state by zone electrophoresis on starch or on ‘Hyflo-super-cel’. This fraction is rich in dicarboxylic amino acids and in glycine. The free α-amino groups belong principally to glutamic acid and aspartic acid; the free α-carboxylic groups to glycine, tryptophan and threonine. The molecular proportions of the ‘oses’ and of ‘osamine’ are as follows: galactose 10, glucose 2, mannose 7, fucose 7, osamine 11. The large proportion of fucose is characteristic, and the oses/osamine ratio is quite low (2.36), as a consequence of the high level of osamine. Donaggio's substance is thus rather distinct from the urinary glycoprotein isolated by adsorption on benzoic acid and from the glycoprotein that inhibits the hemagglutination with different viruses.