This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Cryo-electron microscopy provides density maps of biomolecular complexes in their functional states, but only at low resolution, unlike X-ray crystallography, which provides atomic-resolution structures of biomolecules but usually not in a physiological state. Computational methods to combine information from both techniques hold the promise of generating physiologically accurate, high-resolution structures of biomolecular complexes. To combine experimental data from these two sources, the Resource developed a novel method, molecular dynamics flexible fitting (MDFF;www.ks.uiuc.edu/Research/mdff) [1,2], to fit atomic structures into cryo-EM density maps. MDFF employs molecular dynamics (MD) to perform the fitting, which allows flexibility while maintaining a realistic conformation. The standard MD force field is modified by incorporating the EM density map as an attractive potential that drives atoms into high-density regions. Furthermore, restraints are applied to preserve secondary structure of the biomolecules. MDFF setup and analysis are performed with the Resource's molecular visualization program, VMD, and MDFF simulations are conducted using the Resource's MD simulation software, NAMD. Since NAMD is highly scalable and supports simulation of large systems, MDFF can be applied to large macromolecular complexes such as the ribosome [3].

Agency
National Institute of Health (NIH)
Institute
National Center for Research Resources (NCRR)
Type
Biotechnology Resource Grants (P41)
Project #
5P41RR005969-22
Application #
8363655
Study Section
Special Emphasis Panel (ZRG1-BCMB-E (40))
Project Start
2011-08-01
Project End
2012-09-09
Budget Start
2011-08-01
Budget End
2012-07-31
Support Year
22
Fiscal Year
2011
Total Cost
$66,312
Indirect Cost
Name
University of Illinois Urbana-Champaign
Department
Type
Organized Research Units
DUNS #
041544081
City
Champaign
State
IL
Country
United States
Zip Code
61820
Decker, Karl; Page, Martin; Aksimentiev, Aleksei (2017) Nanoscale Ion Pump Derived from a Biological Water Channel. J Phys Chem B 121:7899-7906
Wolfe, Aaron J; Si, Wei; Zhang, Zhengqi et al. (2017) Quantification of Membrane Protein-Detergent Complex Interactions. J Phys Chem B 121:10228-10241
Radak, Brian K; Chipot, Christophe; Suh, Donghyuk et al. (2017) Constant-pH Molecular Dynamics Simulations for Large Biomolecular Systems. J Chem Theory Comput 13:5933-5944
Sun, Chang; Taguchi, Alexander T; Vermaas, Josh V et al. (2016) Q-Band Electron-Nuclear Double Resonance Reveals Out-of-Plane Hydrogen Bonds Stabilize an Anionic Ubisemiquinone in Cytochrome bo3 from Escherichia coli. Biochemistry 55:5714-5725
Belkin, Maxim; Aksimentiev, Aleksei (2016) Molecular Dynamics Simulation of DNA Capture and Transport in Heated Nanopores. ACS Appl Mater Interfaces 8:12599-608
Poudel, Kumud R; Dong, Yongming; Yu, Hang et al. (2016) A time course of orchestrated endophilin action in sensing, bending, and stabilizing curved membranes. Mol Biol Cell 27:2119-32
Vermaas, Josh V; Taguchi, Alexander T; Dikanov, Sergei A et al. (2015) Redox potential tuning through differential quinone binding in the photosynthetic reaction center of Rhodobacter sphaeroides. Biochemistry 54:2104-16
Belkin, Maxim; Chao, Shu-Han; Jonsson, Magnus P et al. (2015) Plasmonic Nanopores for Trapping, Controlling Displacement, and Sequencing of DNA. ACS Nano 9:10598-611
Han, Wei; Schulten, Klaus (2014) Fibril elongation by A?(17-42): kinetic network analysis of hybrid-resolution molecular dynamics simulations. J Am Chem Soc 136:12450-60
Chaudhry, Jehanzeb Hameed; Comer, Jeffrey; Aksimentiev, Aleksei et al. (2014) A Stabilized Finite Element Method for Modified Poisson-Nernst-Planck Equations to Determine Ion Flow Through a Nanopore. Commun Comput Phys 15:

Showing the most recent 10 out of 367 publications