The detailed structural and mechanical properties of a @entity68386 (TOCL) bilayer were determined using neutron spin echo (NSE) spectroscopy, small angle neutron and X-ray scattering (SANS and SAXS, respectively), and @entity74 ( @entity74 ) simulations. We used @entity74 simulations to develop a scattering density profile (SDP) model, which was then utilized to jointly refine SANS and SAXS data. In addition to commonly reported lipid bilayer structural parameters, component distributions were obtained, including the volume probability, electron density and neutron scattering length density. Of note, the distance between electron density maxima DHH (39.4   ) and the @entity7294 chain thickness 2DC (29.1   ) of TOCL bilayers were both found to be larger than the corresponding values for @entity14146 ( @entity14146 ) bilayers. Conversely, TOCL bilayers have a smaller overall bilayer thickness DB (36.7   ), primarily due to their smaller headgroup volume per @entity1391 . SDP analysis yielded a lipid area of 129.8   (2), indicating that the cross-sectional area per oleoyl chain in TOCL bilayers (i.e., 32.5   (2)) is smaller than that for @entity14146 bilayers. Multiple sets of @entity74 simulations were performed with the lipid area constrained at different values. The calculated surface tension versus lipid area resulted in a lateral area compressibility modulus KA of 342 mN m(-1), which is slightly larger compared to @entity14146 bilayers. Model free comparison to experimental scattering data revealed the best simulated TOCL bilayer from which detailed molecular interactions were determined. Specifically, Na(+) cations were found to interact most strongly with the glycerol hydroxyl linkage, followed by the @entity1391 and backbone carbonyl oxygens. Inter- and intra-lipid interactions were facilitated by @entity3884 bonding between the glycerol hydroxyl and phosphate oxygen, but not with the backbone @entity6738 . Finally, analysis of the intermediate scattering functions from NSE spectroscopy measurements of TOCL bilayers yielded a bending modulus KC of 1.06 * 10(-19) J, which was larger than that observed in @entity14146 bilayers. Our results show the physicochemical properties of cardiolin bilayers that may be important in explaining their functionality in the inner mitochondrial membrane.

Structural and mechanical properties of cardiolipin lipid bilayers determined using neutron spin echo, small angle neutron and X-ray scattering, and XXXX simulations.

@entity3884 :: ('MESH:D006859', 'Chemical') :: ['hydrogen'] @entity7294 :: ('CHEBI:24632', 'Chemical') :: ['hydrocarbon'] @entity68386 :: ('CHEBI:60356', 'Chemical') :: ['tetraoleoyl cardiolipin'] @entity1391 :: ('CHEBI:26020', 'Chemical') :: ['phosphate'] @entity74 :: ('MESH:D030342', 'Disease') :: ['molecular dynamics', 'MD'] @entity6738 :: ('CHEBI:23019', 'Chemical') :: ['carbonyl'] @entity14146 :: ('MESH:C017251', 'Chemical') :: ['DOPC', 'dioleoyl phosphatidylcholine']
@entity74 :: (MESH:D030342,Disease) :: ['molecular dynamics']
