Sampling free energy surfaces as slices by combining umbrella sampling and metadynamics

Sampling free energy surfaces as slices by combining umbrella sampling and metadynamics

Metadynamics (MTD) is a very powerful technique to sample high-dimensional free energy landscapes, and due to its self-guiding property, the method has been successful in studying complex reactions and conformational changes. MTD sampling is based on filling the free energy basins by biasing potentials and thus for cases with flat, broad, and unbound free energy wells, the computational time to...

Finite temperature free energy calculations in NWChem: Metadynamics and Umbrella Sampling-WHAM

Umbrella sampling

The calculation of free-energy differences is one of the main challenges in computational biology and biochemistry. Umbrella sampling, biased molecular dynamics (MD), is one of the methods that provide free energy along a reaction coordinate. Here, the method is derived in a historic overview and is compared with related methods like thermodynamic integration, slow growth, steered MD, or the Ja...

Unraveling the Allosteric Inhibition Mechanism of PTP1B by Free Energy Calculation Based on Umbrella Sampling

Protein tyrosine phosphatase 1B (PTP1B) is a promising target for the treatment of obesity and type II diabetes. Allosteric inhibitors can stabilize an active conformation of PTP1B by hindering the conformational transition of the WPD loop of PTP1B from the open to the closed state. Here, the umbrella sampling molecular dynamics (MD) simulations were employed to compute the reaction path of the...

Biomolecular free energy profiles by a shooting/umbrella sampling protocol, "BOLAS".

We develop an efficient technique for computing free energies corresponding to conformational transitions in complex systems by combining a Monte Carlo ensemble of trajectories generated by the shooting algorithm with umbrella sampling. Motivated by the transition path sampling method, our scheme "BOLAS" (named after a cowboy's lasso) preserves microscopic reversibility and leads to the correct...