Extensins glycosylation

Although the principal cell wall components of plants are carbohydrates, proteins account for 5-10% of the mass.165 Predominant among these are glycoprotein extensins. Like collagen, they are rich in 4-hydroxyproline which is glycosylated with arabi-nose oligosaccharides and galactose (p. 181). Other... 

Karr, A. L. Isolation of an Enzyme System which will Catalyze the Glycosylation of Extensin. Plant Physiol. 50, 275 (1972). 

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