Mucoproteins classification

In this classification of the compounds into mucopolysaccharides, mucoproteins, and mucolipids, it must be emphasized most strongly that since the mode of isolation of any naturally occurring high polymer influences profoundly its composition and biological properties, the difference between divisions is not always sharp and there may be some degree of overlapping. 

In view of the small amount of firmly bound carbohydrate in purified elastin it is doubtful if there could be any useful purpose in regarding the fiber substance as a mucoprotein many albumins and globulins contain similar small residues of carbohydrate and to describe them all as muco-proteins would only serve to negate the value of an accepted and useful system of classification. 

The most radical change of classification in this group is the abandonment of Levene s definition that the carbohydrate group of all mucoproteins is conjugated with sulfuric acid. ... 

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