Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 May 15;8(6):1669-1677.
doi: 10.1021/acsptsci.5c00030. eCollection 2025 Jun 13.

Multivalent Tranexamic Acid (TXA) and Benzamidine Derivatives for Serine Protease Inhibition

Tanmaye Nallan Chakravarthula  1   2 , Rodrigo Santillan-Rodriguez  1 , Ziqian Zeng  1   2 , Abigail Hall  1 , Andres Prieto Trujillo  1 , Anushri Umesh  1   2 , Nathan J Alves  1   2
Affiliations

Multivalent Tranexamic Acid (TXA) and Benzamidine Derivatives for Serine Protease Inhibition

Tanmaye Nallan Chakravarthula et al. ACS Pharmacol Transl Sci. .

Abstract

Blood coagulation and fibrinolysis pathways involve many serine proteases in a careful equilibrium. Disruption of this hemostatic balance can cause life-threatening thromboembolic and bleeding disorders that require therapeutic intervention. Heterobivalent molecules synthesized with both benzamidine (active site serine protease inhibitor) and tranexamic acid (TXA, kringle/lysine-site inhibitor) of increasing dPEG linker lengths (dPEG4-dPEG36) were synthesized and analyzed for plasmin, thrombin, and tissue plasminogen activator (tPA) inhibition using soluble enzymatic substrates. Linker lengths greater than the active and lysine binding site separation achieved improved inhibition with plasmin and tPA due to multivalent subsite binding effects. Despite TXA being a weak active site inhibitor, homomultivalent TXA (PAMAM8-TXA) demonstrated strong competitive plasmin inhibition (K i = 2.5 ± 1.8 μM) due to the statistical rebinding effect. IC50 values were also determined by assaying on physiologically relevant, fluorescently tagged, annular fibrin clots to capture the effect of kringle binding inhibition on fibrinolytic potential in the presence and absence of inhibitors.

Keywords: benzamidine; enzyme inhibition; multivalency; serine proteases; tranexamic acid.

PubMed Disclaimer

Similar articles

See all similar articles

References

    1. Di Cera E.. Serine Proteases. IUBMB Life. 2009;61(5):510–515. doi: 10.1002/iub.186. - DOI - PMC - PubMed
    1. Abel R., Salam N. K., Shelley J., Farid R., Friesner R. A., Sherman W.. Contribution of Explicit Solvent Effects to the Binding Affinity of Small-Molecule Inhibitors in Blood Coagulation Factor Serine Proteases. ChemMedChem. 2011;6(6):1049–1066. doi: 10.1002/cmdc.201000533. - DOI - PubMed
    1. Loof T. G., Deicke C., Medina E.. The Role of Coagulation/Fibrinolysis during Streptococcus Pyogenes Infection. Front. Cell. Infection Microbiol. 2014;4(SEP):128. doi: 10.3389/fcimb.2014.00128. - DOI - PMC - PubMed
    1. Syrovets T., Simmet T.. Novel Aspects and New Roles for the Serine Protease Plasmin. CMLS Cell. Mol. Life Sci. 2004;61:873–885. doi: 10.1007/s00018-003-3348-5. - DOI - PMC - PubMed
    1. Adivitiya, Khasa Y. P.. The Evolution of Recombinant Thrombolytics: Current Status and Future Directions. Bioengineered. 2017;8(4):331–358. doi: 10.1080/21655979.2016.1229718. - DOI - PMC - PubMed