High‐molecular‐weight kininogen is a binding protein for tissue prokallikrein

FEBS Letters

Raab, Armin¹  Kemme, Michael¹ 

[1] Institute for Biochemistry, Darmstadt University of Technology, Petersenstr. 22, 64287 Darmstadt, Germany

关键词: Binding protein;    Kininogen;    Tissue prokallikrein;    Zymogen;    BSA (HSA);    bovine (human) serum albumin;    ELISA;    enzyme-linked immunosorbent assay;    HK;    high-molecular-weight kininogen;    LK;    low-molecular-weight kininogen;    PBS;    phosphate-buffered saline;    SDS–PAGE;    sodium dodecyl sulfate–polyacrylamide gel electrophoresis;   

DOI  :  10.1016/S0014-5793(00)01141-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Human tissue prokallikrein, a zymogen of the kallikrein-kinin system, circulates in plasma bound to neutrophils. Because plasma kininogens contribute to the assembly of kinin-generating components on blood cells, these proteins were assessed for their ability to complex the kallikrein precursor. Using ligand blot and direct binding assays, biotinylated prokallikrein was found to bind only to high-molecular-weight kininogen and not to the low-molecular-weight form. The interaction was specific, reversible, and saturable yielding an estimated dissociation constant K _D=690 nM and a 1:1 stoichiometry. Specific kininogen binding of tissue prokallikrein also occurred at physiological plasma protein concentrations. These results provide the first evidence for a novel function of high-molecular-weight kininogen as a binding protein for tissue prokallikrein that could serve to localize the kallikrein precursor on the neutrophil surface.

【 授权许可】

Unknown