Glycoproteins sialic acid-rich

The surfactant contains four unique proteins, designated SP-A, SP-B, SP-C, and SP-D.c e The major protein (SP-A) is a sialic acid-rich glycoprotein derived from a 26-kDa peptide, which contains a short collagen-like domain.eTk Like collagen, this domain contains glycosylated hydroxyproline. 

Carlson, D. M., Isolation of a Sialic Acid-Rich Glycoprotein from an... 

Basic Fuschin 550 Glycoprotein, nucleic acids, sialic acid-rich glycoproteins... 

Whyte and Loke 1978, Rosati and de Santis 1980). Despite good evidence, it is still not certain that the immune barrier between mother and child is achieved solely by sialic acid-rich glycoproteins. Of at least equal importance is the fact that the maternal organism synthesizes immunosuppressive factors in the early phase of pregnancy (Beer and Billingham 1978, Noonan et al. 1979). 

This fraction contained carbohydrates typical of membrane glycoproteins and was especially rich in galactose and sialic acid. Glycoproteins in this fraction avidly bound the lectin Concanavalin A. 

The basic role of platelets is haemostasis, or stopping bleeding, when tissue is damaged. The platelets adhere to exposed subendothelium on vessel walls, are activated and aggregate to form a thrombus that covers the damaged area or blocks oif complete vessels when they are involved. These functions involve a number of receptors, all of which are membrane glycoproteins. Platelets are very rich in glycoproteins and contain some 11 times more sialic acid than erythrocytes. 

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