Pattern of sialoglycoproteins obtained by chromatofocusing of chicken liver and hepatoma Mc-29 microsomal preparations labelled in vivo with 3H-leucine and N-acetyl-14C-mannosamine.

Chromatofocusing has been used for separation of chicken liver and virus-induced hepatoma Mc-29 microsomal glycoproteins double labelled in vivo with 3H-leucine and N-acetyl-14C-mannosamine. The sialoglycoprotein profile was obtained by plotting the pH-values, as well as the values of the calculated specific activity (SA-cpm/mg protein) in each fraction, in the graphs. Different patterns for liver and hepatoma sialoglycoproteins were detected. Unlike liver microsomes in which the highest labelled compounds were registered in the alkaline zone of the pH-gradient, special feature for the hepatoma sialoglycoprotein pattern was the presence of highly labelled fraction eluted in the acidic zone of the pH-gradient. A term named "sialylation rate" of a separated sialoglycoproteins was involved. It has been found that liver sialoglycoproteins are more or less uniformly sialylated, independently of the pI-values, while those from hepatoma with acidic pI were sialylated at a higher extent in comparison to the fractions with alkaline pI.