VTechWorks staff will be away for the Thanksgiving holiday beginning at noon on Wednesday, November 27, through Friday, November 29. We will resume normal operations on Monday, December 2. Thank you for your patience.
 

Molecular simulation study of structural and dynamic properties of mixed DPPC/DPPE bilayers

Simple item page
dc.contributorVirginia Techen
dc.contributor.authorLeekumjorn, S.en
dc.contributor.authorSum, A. K.en
dc.contributor.departmentChemical Engineeringen
dc.date.accessed2014-02-05en
dc.date.accessioned2014-02-26T19:10:06Zen
dc.date.available2014-02-26T19:10:06Zen
dc.date.issued2006-06-01en
dc.description.abstractMolecular dynamics simulations have been used to study structural and dynamic properties of fully hydrated mixed 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (DPPE) bilayers at 0, 25, 50, 75, and 100 mol % DPPE. Simulations were performed for 50 ns at 350 K and 1 bar for the liquid-crystalline state of the mixtures. Results show that the average area per headgroup reduces from 0.65 +/- 0.01 nm(2) in pure DPPC to 0.52 +/- 0.01 nm 2 in pure DPPE systems. The lipid tails become more ordered with increasing DPPE concentration, resulting in a slight increase in membrane thickness (3.43 +/- 0.01 nm in pure DPPC to 4.00 +/- 0.01 nm in pure DPPE). The calculated area per headgroup and order parameter for pure DPPE deviates significantly from available experimental measurements, suggesting that the force field employed requires further refinement. In-depth analysis of the hydrogen-bond distribution in DPPE molecules shows that the amine groups strongly interact with the phosphate and carbonyl groups through inter/intramolecular hydrogen bonds. This yields a bilayer structure with DPPE headgroups preferentially located near the lipid phosphate and ester oxygens. It is observed that increasing DPPE concentrations causes competitive hydrogen bonding between the amine groups (hydrogen-donor) and the phosphate/carbonyl groups or water (hydrogen-acceptor). Due to the increasing number of hydrogen-donors from DPPE molecules with increasing concentration, DPPE becomes more hydrated. Trajectory analysis shows that DPPE molecules in the lipid mixtures move laterally and randomly around the membrane surface and the movement becomes more localized with increasing DPPE concentrations. For the conditions and simulation time considered, no aggregation or phase separation was observed between DPPC and DPPE.en
dc.format.mimetypeapplication/pdfen
dc.identifier.citationLeekumjorn, S; Sum, AK. "Molecular simulation study of structural and dynamic properties of mixed DPPC/DPPE bilayers," Biophysical Journal 90(11), 3951-3965 (2006); doi: 10.1529/biophysj.105.076596en
dc.identifier.doihttps://doi.org/10.1529/biophysj.105.076596en
dc.identifier.issn0006-3495en
dc.identifier.urihttp://hdl.handle.net/10919/25781en
dc.identifier.urlhttp://www.sciencedirect.com/science/article/pii/S0006349506725784en
dc.language.isoen_USen
dc.publisherCELL PRESSen
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subjectParticle-mesh ewalden
dc.subjectPhosphatidylethanolamine lipid-bilayersen
dc.subjectRangeen
dc.subjectElectrostatic interactionsen
dc.subjectH-2 NMR-spectroscopyen
dc.subjectPhospholipid membraneen
dc.subjectOrder parametersen
dc.subjectSaccharomyces-cerevisiaeen
dc.subjectMagnetic resonanceen
dc.subjectSystemsen
dc.subjectPhosphatidylcholinesen
dc.titleMolecular simulation study of structural and dynamic properties of mixed DPPC/DPPE bilayersen
dc.title.serialBiophysical Journalen
dc.typeArticle - Refereeden
dc.type.dcmitypeTexten

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
1-s2.0-S0006349506725784-main.pdf
Size:
9.55 MB
Format:
Adobe Portable Document Format
Description:
Main article
Download

Collections

Scholarly Works, Chemical Engineering