Membranes and their embedded ion channels play a crucial role in numerous cell processes such as: signaling, energy conversion, and ion conductance. The long term goal of the proposed studies is to provide a detailed understanding of the biophysical properties of these biological membranes through molecular modeling. For this proposal, we aim to obtain a detailed description of oligomeric ion channel structure and dynamics embedded within a membrane. Completion of this aim will promote public health by providing essential information needed for the rational design of novel antimicrobial, antiviral, and pharmaceutical agents which target ion channels. The knowledge gained has the potential to further enable humans to combat many diseases and to alleviate some of the shortcomings currently encountered with today's therapeutics. We propose to elucidate the spatial (about 1 micrometer) and temporal (about 1 millisecond) mesoscale salient features of membrane associated ion channels using coarse grain molecular modeling, such as the mechanism of formation from monomeric peptides. Currently, these spatial and temporal regions are difficult to determine either experimentally or with conventional simulation methodologies. These novel coarse grain methods allow us to elucidate fundamental membrane mechanisms such as oligomerization.
The specific aims are a carefully planned series of simulations to examine the interactions of ion channels embedded within membranes. The goal is to quantify the structural and dynamical properties of ion channels and their interactions with membranes. Calculations will begin with the structural and dynamical characterization of single transmembrane amphipathic peptides, and we will simultaneously analyze the perturbations caused by the peptide on the lipid membrane. Additionally, we will measure the structural and dynamical characteristics of homo-oligomeric ion channels composed of several transmembrane amphipathic peptides. Ultimately, we aim to calculate the binding free energy of ion channel formation, and elucidate the mechanism of formation of homo-oligomeric ion channels from monomeric peptides.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Academic Research Enhancement Awards (AREA) (R15)
Project #
1R15GM075990-01
Application #
7011345
Study Section
Biochemistry and Biophysics of Membranes Study Section (BBM)
Program Officer
Chin, Jean
Project Start
2006-01-01
Project End
2008-06-30
Budget Start
2006-01-01
Budget End
2008-06-30
Support Year
1
Fiscal Year
2006
Total Cost
$228,336
Indirect Cost
Name
University of the Sciences Philadelphia
Department
Chemistry
Type
Schools of Arts and Sciences
DUNS #
079497681
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Nguyen, Thuy Hien T; Liu, Zhiwei; Moore, Preston B (2013) Molecular dynamics simulations of homo-oligomeric bundles embedded within a lipid bilayer. Biophys J 105:1569-80
Pantano, Diego A; Klein, Michael L; Discher, Dennis E et al. (2011) Morphologies of charged diblock copolymers simulated with a neutral coarse-grained model. J Phys Chem B 115:4689-95
Nguyen, Thuy Hien T; Rao, Niny Z; Schroeder, William M et al. (2010) Coarse-grained molecular dynamics of tetrameric transmembrane peptide bundles within a lipid bilayer. Chem Phys Lipids 163:530-7
Kalescky, Robert J B; Shinoda, Wataru; Moore, Preston B et al. (2009) Area per ligand as a function of nanoparticle radius: a theoretical and computer simulation approach. Langmuir 25:1352-9