Heparin binding sites are located in a 40-kD γ-chain and a 36-kD β-chain fragment isolated from human fibrinogen.

Autor: Mohri, Hiroshi, Iwamatsu, Akihiko, Ohkubo, Takao
Zdroj: Journal of Thrombosis & Thrombolysis; Feb1994, Vol. 1 Issue 1, p49-54, 6p
Abstrakt: Objective: We have previously shown thatI-fibrinogen binds to heparin sepharose CL-6B. To identify the localization of the heparin binding domain in human fibrinogen, reduced and alkylated fibrinogen was digested by limited- Staphylococcus aureus V8 protease. Methods/Results: Two fragments have now been isolated and purified to apparent homogeneity by heparin-affinity chromatography. These fragments, denoted the 40-kD and 36-kD fragments, contain NH-terminal sequences of Ala-Ser-Ile-Leu-Thr-His-Asp and Thr-Val-Asn-Ser-Asn-Ile-Pro, respectively. These fragments established the positions of these peptides within the γ chain of fibrinogen as beginning with the residue tentatively designated 124 and within the B chain as beginning with the residue designated 186. Binding ofI-fibrinogen to heparinsepharose CL-6B was completely inhibited by a mixture of these fragments, with an IC of 3.2 μM. The synthetic peptide of the γ chain carboxy-terminal 15 residues (GQQHHLGGAKQAGDV;G15) partially inhibited fibrinogen binding. The mixture of these fragments partially inhibited the ADP-induced aggregation of platelets. Conclusions: These data indicate that the domains for heparin binding may be present on both the γ chain and the β chain of fibrinogen, and that the domain on the γ chain may be close to the binding domain on the carboxy terminus of the fibrinogen γ chain to glycoprotein IIb-IIIa. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index
Externí odkaz: