Human platelets incorporated glucosamine and mannose into protein. Incorporation in whole or disrupted cells was reduced considerably by incubation with thrombin. The effect of thrombin appeared to be due to hydrolysis of glycoprotein. Cyanide and fluoride also markedly inhibited incorporation; concanavalin A, prostaglandin E1, aspirin, ADP, and puromycin had no effect. Neither concanavalin A, ADP or prostaglandin E1 blocked the inhibition of incorporation by thrombin. The experiments indicate that human platelets add carbohydrate onto pre-existing protein by an energy-dependent process and that this glycoprotein is hydrolyzed by thrombin.
ASJC Scopus subject areas
- Molecular Biology