Functional properties of complement factor H-related proteins FHR-3 and FHR-4: binding to the C3d region of C3b and differential regulation by heparin

被引：108

作者：

Hellwage, J

Jokiranta, TS

Koistinen, V

Vaarala, O

Meri, S

Zipfel, PF

机构：

[1] Bernhard Nocht Inst Trop Med, D-20359 Hamburg, Germany

[2] Haartman Inst, FIN-00290 Helsinki, Finland

[3] HD Diagnost, Dept Bacteriol & Immunol, FIN-00290 Helsinki, Finland

[4] Natl Publ Hlth Inst, Dept Biochem, FIN-00300 Helsinki, Finland

[5] Univ Jena, Clin Anaesthesiol & Intens Care Med, D-07740 Jena, Germany

来源：

FEBS LETTERS | 1999年 / 462卷 / 03期

基金：

芬兰科学院;

关键词：

complement regulation; heparin binding; surface plasmon resonance; alternative pathway; Streptococcus pneumoniae;

D O I：

10.1016/S0014-5793(99)01554-9

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

The human factor H-related proteins FHR-3 and FHR-4 are members of a family of proteins related to the complement factor H. Here, we report that the two proteins bind to the C3d region of complement C3b, The apparent KA values for the interactions of FHR-3 and FHR-4 with C3b are 7.5 X 10(6) M-1 and 2.9 X 10(6) M-1, respectively. Binding studies performed with C3b-coated pneumococci confirmed the results obtained with the biosensor system. A C-terminal construct of factor H showed similar binding characteristics. The interaction of FHR-3, but not of FHR-4, with opsonised pneumococci was inhibited by heparin, (C) 1999 Federation of European Biochemical Societies.

引用

页码：345 / 352

页数：8

共 34 条

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