All Six Modules of the Gelatin-binding Domain of Fibronectin Are Required for Full Affinity

摘要: The gelatin-binding sites of fibronectin are confined to a 42-kDa region having four type I and two II modules in the following order: I(6)-II(1)-II(2)-I(7)-I(8)-I(9). To determine relative importance each module for recognition gelatin, recombinant green fluorescent fusion proteins were prepared which individual or groups deleted, resulting tested binding gelatin by analytical affinity chromatography. Deletion both did not eliminate binding, confirming that at least some this able bind gelatin. It was found deletion 6 tends increase affinity, whereas any other decreases it. I(9) had large effect but only if II(2) also present, suggesting an interaction between these noncontiguous modules. Analysis more than 20 products led conclusion all contribute either directly contacting ligand indirectly through module-module interactions.