The goal of this proposal is to develop a new computational method to efficiently quantify protein-ligand association in a way that explicitly considers protein flexibility. Molecular recognition between molecules through noncovalent association plays a fundamental role in virtually all processes in biological systems. Although many computational concepts exist to simulate drug-protein recognition, an efficient and accurate quantification of these interactions has still not been achieved. We propose a novel computational method that addresses some of the most serious shortcomings of present approaches: protein flexibility and a reliable quantification of binding affinities. We introduce the new concept of a hypothetical 'ligand model': a virtual ligand that binds to the protein and dynamically changes its shape and properties during molecular dynamics (MD) simulations, essentially representing a large ensemble of different chemical species binding to the same target protein. This approach allows sampling protein conformations relevant to its interaction with chemicals or drug candidates. This method also will allow us to probe conformational flexibility of the protein upon ligand binding. The 'ligand-model'concept will result in an efficient decoupling of sampling using MD simulations and subsequent docking. This method consequently combines both accuracy in quantifying molecular recognition and efficiency in virtual screening of large compound libraries. The software is anticipated to be of wide interest for researchers in all areas of protein-ligand interactions, including drug design, structural biology, and environmental toxicology.

Public Health Relevance

Molecular recognition between molecules through noncovalent association plays a fundamental role in virtually all processes in biological systems. This project is aimed toward developing a novel computational method to efficiently quantify protein-ligand binding, explicitly including the dynamics of the protein. It will have wide applicability for drug design and environmental toxicology.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21GM085604-02
Application #
7663070
Study Section
Macromolecular Structure and Function D Study Section (MSFD)
Program Officer
Preusch, Peter C
Project Start
2008-08-01
Project End
2011-05-31
Budget Start
2009-06-01
Budget End
2011-05-31
Support Year
2
Fiscal Year
2009
Total Cost
$148,714
Indirect Cost
Name
Purdue University
Department
Pharmacology
Type
Schools of Pharmacy
DUNS #
072051394
City
West Lafayette
State
IN
Country
United States
Zip Code
47907
Danielson, Matthew L; Lill, Markus A (2012) Predicting flexible loop regions that interact with ligands: the challenge of accurate scoring. Proteins 80:246-60
Xu, Mengang; Lill, Markus A (2012) Utilizing experimental data for reducing ensemble size in flexible-protein docking. J Chem Inf Model 52:187-98
Cueva, Juan Pablo; Chemel, Benjamin R; Juncosa Jr, Jose I et al. (2012) Analogues of doxanthrine reveal differences between the dopamine D1 receptor binding properties of chromanoisoquinolines and hexahydrobenzo[a]phenanthridines. Eur J Med Chem 48:97-107
Xu, Mengang; Lill, Markus A (2011) Significant enhancement of docking sensitivity using implicit ligand sampling. J Chem Inf Model 51:693-706
Bonner, Lisa A; Laban, Uros; Chemel, Benjamin R et al. (2011) Mapping the catechol binding site in dopamine D? receptors: synthesis and evaluation of two parallel series of bicyclic dopamine analogues. ChemMedChem 6:1024-40
Lill, Markus A; Thompson, Jared J (2011) Solvent interaction energy calculations on molecular dynamics trajectories: increasing the efficiency using systematic frame selection. J Chem Inf Model 51:2680-9
Lill, Markus A (2011) Efficient incorporation of protein flexibility and dynamics into molecular docking simulations. Biochemistry 50:6157-69
Danielson, Matthew L; Desai, Prashant V; Mohutsky, Michael A et al. (2011) Potentially increasing the metabolic stability of drug candidates via computational site of metabolism prediction by CYP2C9: The utility of incorporating protein flexibility via an ensemble of structures. Eur J Med Chem 46:3953-63
Cueva, Juan Pablo; Gallardo-Godoy, Alejandra; Juncosa, Jose I et al. (2011) Probing the steric space at the floor of the D1 dopamine receptor orthosteric binding domain: 7ýý-, 7ýý-, 8ýý-, and 8ýý-methyl substituted dihydrexidine analogues. J Med Chem 54:5508-21