The Biosynthesis of Glycoproteins III. GLUCOSAMINE INTERMEDIATES IN PLASMA GLYCOPROTEIN SYNTHESIS IN LIVERS
نویسنده
چکیده
It was previously shown that the particulate fraction of liver was the site of incorporation of glucosamine-l-14C into rat plasma glycoproteins (1). In continuing these studies, we wished to determine whether this incorporation was dependent on the synthesis of protein de nova. Since puromycin inhibits protein biosynthesis (2-5), we have studied the effect of this drug on the incorporation of glucosamine into liver and plasma proteins in viva. Puromycin inhibited the incorporation of glucosamine-r4C into liver and plasma proteins, and there was an accumulation of radioactive glucosamine derivatives in the acid-soluble fraction of the liver. The nature of these compounds has been elucidated.
منابع مشابه
The Metabolism of Plasma Glycoproteins II. Studies on the Rate of Incorporation of Glucosamine-l-14C into Protein-bound Hexosamine in the Rat Bearing Walker 256 Carcinoma1
The origin of the elevated serum glycoproteins observed in rats bearing 6and 12-day-old Walker 256 carcinoma has been studied utilizing glucosamine-l-l4C as a precursor. The results indicate that the liver is quantitatively the major site of serum glycoprotein biosynthesis as is the case in the normal animal. While the rate of incorporation of glucosamine-l-14C into hepatic protein-bound hexosa...
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The origin of the elevated serum glycoproteins observed in rats bearing 6and 12-day-old Walker 256 carcinoma has been studied utilizing glucosamine-l-l4C as a precursor. The results indicate that the liver is quantitatively the major site of serum glycoprotein biosynthesis as is the case in the normal animal. While the rate of incorporation of glucosamine-l-14C into hepatic protein-bound hexosa...
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It was previously shown that the particulate fraction of liver was the site of incorporation of glucosamine-l-14C into rat plasma glycoproteins (1). In continuing these studies, we wished to determine whether this incorporation was dependent on the synthesis of protein de nova. Since puromycin inhibits protein biosynthesis (2-5), we have studied the effect of this drug on the incorporation of g...
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