Sialic Acid Dependent Polypeptide Chain Heterogeneity of Human Fibrinogen Demonstrated by Two-Dimensional Electrophoresis

Summary

Human fibrinogen was compared with asialofibrinogen by two-dimensional electrophoresis to evaluate the contribution of sialic acid to the heterogeneity of the γ- and Bβ-polypeptide chains.

Reduced fibrinogen showed three major variants for both the γ- and Bβ-chains. In addition two minor γ-bands with a more acidic isoelectric point than the normal γ-chains were observed. Electrophoresis in the second dimension (SDS) suggests that these most acidic bands are γ-chain-variants with a higher molecular weight. In asialofibrinogen only two predominant variants with more alkaline isoelectric points were present in each chain type.

It is concluded that enzymatic removal of sialic acid partially reduces the heterogeneity of the γ- and Bβ-polypeptide chains of human fibrinogen, but additional sources producing charge heterogeneity must be sought.

Key words

Key words Fibrinogen - Heterogeneity - Sialic acid - Two-dimensional electrophoresis

• References

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