Mapping of the fibrinogen-binding site on the staphylocoagulase C-terminal repeat region.

ABSTRACT: Fibrin (Fbn) deposits are a hallmark of staphylocoagulase (SC)-positive endocarditis. Binding of the N terminus of Staphylococcus aureus SC to host prothrombin triggers formation of an active SC·prothrombin∗ complex that cleaves host fibrinogen to Fbn. In addition, the C-terminal domain of the prototypical SC contains one pseudorepeat (PR) and seven repeats (R1 → R7) that bind fibrinogen/Fbn fragment D (frag D) by a mechanism that is unclear. Here, we define affinities and stoichiometries of frag D binding to C-terminal SC constructs, using fluorescence equilibrium binding, NMR titration, alanine scanning, and native PAGE. We found that constructs containing the PR and single repeats bound frag D with K_D ∼50 to 130 nM and a 1:1 stoichiometry, indicating a conserved binding site

SUBMITTER: Maddur AA 

PROVIDER: S-EPMC8761706 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature