Assessing the Interactions between Snake Venom Metalloproteinases and Hydroxamate Inhibitors Using Kinetic and ITC...

Area of Science:

• Biochemistry and Pharmacology
• Toxicology
• Computational Chemistry

Background:

• Bothrops snakebites are a major health issue in Central and South America, causing severe local tissue damage and systemic bleeding.
• Snake venom metalloproteinases (SVMPs) are key toxins responsible for hemorrhage and necrosis, with current antivenom therapy showing limited efficacy against tissue destruction.
• Developing small molecule inhibitors targeting SVMPs offers a promising strategy to complement antivenom treatment for snakebite victims.

Purpose of the Study:

• To computationally assess the interactions between six hydroxamate inhibitors and two P-I SVMPs (Atroxlysin-I and Leucurolysin-a) from Bothrops species.
• To identify scoring functions that accurately predict the binding affinities of these inhibitors to SVMPs.
• To elucidate enzyme-inhibitor interactions that explain the broad-spectrum activity of hydroxamate inhibitors.

Main Methods:

• Docking calculations and molecular dynamics simulations were employed to model inhibitor-SVMP interactions.
• A variety of end-point free energy methods combined with entropic terms were used to develop scoring functions for relative affinities.
• Computational predictions were validated against experimental kinetic activity assay data.

Main Results:

• Six hydroxamate inhibitors were characterized for their inhibitory potential against hemorrhagic and non-hemorrhagic P-I SVMPs.
• The study identified specific enzyme-inhibitor interactions contributing to the broad-spectrum efficacy of the tested molecules.
• Energetic and entropic terms that enhance the performance of scoring functions for predicting inhibitor affinity were identified.

Conclusions:

• Hydroxamate inhibitors show potential as adjunct therapies for Bothrops snakebites, particularly for preventing necrosis.
• Computational approaches, including molecular dynamics and free energy calculations, are valuable tools for designing effective SVMP inhibitors.
• Understanding the detailed interactions between inhibitors and SVMPs can guide the development of more potent and selective snake venom toxins inhibitors.