Title | Atomically detailed lipid bilayer models for the interpretation of small angle neutron and X-ray scattering data |
Author/s |
Joseph C. Fogarty
Department of Physics, University of South Florida, Tampa, FL 33620, USA Mihir Arjunwadkar Centre for Modeling and Simulation, Savitribai Phule Pune University, Pune 411 007, India Sagar A. Pandit, and Jianjun Pan Department of Physics, University of South Florida, Tampa, FL 33620, USA |
Abstract | We present a new atom density profile (ADP) model and a statistical approach for extracting structural characteristics of lipid bilayers from X-ray and neutron scattering data. Models for five lipids with varying head and tail chemical composition in the fluid phase, 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine (DOPC), 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC), 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC), 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylserine (POPS), and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylglycerol (POPG), are optimized using a simplex based method to simultaneously reproduce both neutron and X-ray scattering data. Structural properties are determined using statistical analysis of multiple optimal model structures. The method and models presented make minimal assumptions regarding the atomic configuration, while taking into account the underlying physical properties of the system. The more general model and statistical approach yield data with well defined uncertainties, indicating the precision in determining density profiles, atomic locations, and bilayer structural characteristics. Resulting bilayer structures include regions exhibiting large conformational variation. Due to the increased detail in the model, the results demonstrate the possibility of a distinct hydration layer within the interfacial (backbone) region. |
Keywords | Model membrane; SAXS; SANS; Simplex based optimization |
Download | Journal |
Citing This Document | Joseph C. Fogarty, Mihir Arjunwadkar, Sagar A. Pandit, and Jianjun Pan , Atomically detailed lipid bilayer models for the interpretation of small angle neutron and X-ray scattering data . Technical Report CMS-TR-20141125 of the Centre for Modeling and Simulation, Savitribai Phule Pune University, Pune 411007, India (2014); available at http://cms.unipune.ac.in/reports/. |
Notes, Published Reference, Etc. | Published as Biochimica et Biophysica Acta 1848 (2015) 662-672 |
Contact | pandit AT usf.edu |
Supplementary Material |