Sheep submaxillary gland, glycoproteins

An A-acetylneuraminic acid has been isolated from bovine submaxillary mucin and the urinary glycoprotein (urinary mucoprotein of Tamm and Horsfall) following the enzymic action of the influenza virus on the glycoproteins 108), Gynaminic acid, from milk and meconium appear to be identical to the A-acetylneuraminic acid (sialic acid ) from sheep submaxillary gland and different from that from bovine submaxillary glands and lactaminic acid from bovine colostrum 102b, 109),... 

Molnar et al. (1964) found that puromydn administered to intact rats almost completely inhibited incorporation of both glucosamine-l- C and DL-leucine-l- C into liver and plasma proteins. Inhibition of protein synthesis by puromycin indicates operation of the usual ribosomal mechanism of protein synthesis. Since the great bulk of carbohydrate incorporation into glycoprotein appears to occur by postribosomal mechanisms (see Section IV), inhibition of carbohydrate incorporation by puromycin suggests that there is no appreciable reservoir of nonglycosylated polypeptide in either rat liver or sheep submaxillary gland. 

L-Cysteic acid residues were produced within the peptide chain when submaxillary-gland glycoprotein from sheep was treated with alkali (pH 9.0), during 24 hours at room temperature in the presence of sulfite (0.1 M). The yield was —55% on the basis of the L-serine decomposed, and the corresponding derivative from L-threonine was not detected.167... 

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