The heights of energy barriers separating two (macro-)states are useful for estimating transition frequencies. In non-degenerate landscapes the decomposition of a landscape into basins surrounding local minima connected by saddle points is straightforward and yields a useful definition of macro-states. In this work we develop a rigorous concept of barrier trees for degenerate landscapes. We pre...

Much of the information about the multi-valley structure of disordered spin systems can be convened in a simple tree structure – a barrier tree – the leaves and internal nodes of which represent, respectively, the local minima and the lowest energy saddles connecting those minima. Here we apply several statistics used in the study of phylogenetic trees to barrier trees that result from the ener...

MOTIVATION Energy landscapes provide a valuable means for studying the folding dynamics of short RNA molecules in detail by modeling all possible structures and their transitions. Higher abstraction levels based on a macro-state decomposition of the landscape enable the study of larger systems; however, they are still restricted by huge memory requirements of exact approaches. RESULTS We pres...

Molecular docking programs play a crucial role in drug design and development. In recent years, much attention has been devoted to the protein-peptide docking problem in which docking of a flexible peptide with a known protein is sought. In this work we present a new docking algorithm which is based on the use of a filling function method for continuos constrained global optimization. Indeed, t...

The heavily used protein-protein docking server ClusPro performs three computational steps as follows: (1) rigid body docking, (2) RMSD based clustering of the 1000 lowest energy structures, and (3) the removal of steric clashes by energy minimization. In response to challenges encountered in recent CAPRI targets, we added three new options to ClusPro. These are (1) accounting for small angle X...

{Global optimization approaches are proposed for addressing both the protein folding and peptide docking problems. In the protein folding problem, the ultimate goal involves predicting the native protein conformation. A common approach, based on the thermodynamic hypothesis, assumes that this conformation corresponds to the structure exhibiting the global minimum free energy. However, molecular...

Understanding energetics and mechanism of protein-protein association remains one of the biggest theoretical problems in structural biology. It is assumed that desolvation must play an essential role during the association process, and indeed protein-protein interfaces in obligate complexes have been found to be highly hydrophobic. However, the identification of protein interaction sites from s...

We perform simulations of model proteins to study folding on rugged energy landscapes. We construct "first-passage" networks as the system transitions from unfolded to native states. The nodes and bonds in these networks correspond to basins and transitions between them in the energy landscape. We find power-law relations between the folding time and the number of nodes and bonds. We show that ...

We describe a real-time docking method using molecular graphics and high-speed calculation of the energy of interaction between a drug and a receptor. A three-dimensional tabulation of the potential is computed prior to the docking experiment, and the total interaction energy is calculated and updated on the display screen in real-time to provide immediate visual feedback to the user as the dru...