Steps of the coagulation cascade affected by polyphosphate (polyP). PolyP (red) accelerates factor V activation by factors Xa and thrombin, accelerates factor IX back-activation by thrombin, abrogates the ability of TFPI to inhibit factor Xa, and enhances fibrin polymerization. Fibrin polymerization and contact pathway activation are preferentially stimulated by long-chain (LC) polyP, like that present in microorganisms. Modified from Smith and Morrissey.⁸  Professional illustration by Luk Cox, Somersault18:24.