Mise en évidence d'une activité mannosyl-transferase dans les cellules embryonnaires de poulet et influence de la différenciation cellulaire

Summary The microsomal fractions from chick embryo cells were shown to carry out transfer of mannose from GDP-mannose to endogenous protein acceptors. Data also are presented which support that among the subcellular fractions only the rough microsomes are active in the mannose transfer. The maximum mannosyltransferase activity is obtained with 8-day-old embryos. This observation may be related to the proliferation of rough endoplasmic reticulum with regard to smooth microsomes.     

Analyse immunoélectrophorétique de la gonadotropine choriale humaine

Summary The purity of human chorionic gonadotropin showing an activity of 12,000/mg, is confirmed by immuno-electrophoretic analysis. Characteristic antigenic properties of this hormone are revealed by this method.     

Les sites subcellulaires d'incorporation du 1-14C-l-fucose dans les glycoprotéines des cellules normales et cancéreuses en culture in vitro

Summary Protein macromolecules in which the 1-¹⁴C-l-fucose is incorporated exist in non-specialized cancerous (KB strain) or normal (chick embryo fibroblasts) cells cultivated in vitro. The preferential site of incorporation of this precursor is located at the endoplasmic membranes for cancerous cells and in the cell sap for normal cells.     

Caractérisation de laβ-galactosidase d'Helix pomatia par immunoélectrophorèse

Summary Digestive juice ofHelix pomatia was studied by immunoelectrophoresis: after incubation with a chromogenic substrate, 5-bromo-4-chloroindol-3-yl--D-galactopyranoside, two-galactosidases were revealed.