LEADER 05369nam 22007335 450 001 9910300403403321 005 20200706083308.0 010 $a3-319-22210-4 024 7 $a10.1007/978-3-319-22210-3 035 $a(CKB)3710000000494140 035 $a(EBL)4068110 035 $a(SSID)ssj0001585584 035 $a(PQKBManifestationID)16263750 035 $a(PQKBTitleCode)TC0001585584 035 $a(PQKBWorkID)14865418 035 $a(PQKB)10760116 035 $a(DE-He213)978-3-319-22210-3 035 $a(MiAaPQ)EBC4068110 035 $a(PPN)190536829 035 $a(EXLCZ)993710000000494140 100 $a20151020d2015 u| 0 101 0 $aeng 135 $aur|n|---||||| 181 $ctxt 182 $cc 183 $acr 200 10$aStructure Determination of HIV-1 Tat/Fluid Phase Membranes and DMPC Ripple Phase Using X-Ray Scattering$b[electronic resource] /$fby Kiyotaka Akabori 205 $a1st ed. 2015. 210 1$aCham :$cSpringer International Publishing :$cImprint: Springer,$d2015. 215 $a1 online resource (186 p.) 225 1 $aSpringer Theses, Recognizing Outstanding Ph.D. Research,$x2190-5053 300 $aDescription based upon print version of record. 311 $a3-319-22209-0 320 $aIncludes bibliographical references at the end of each chapters. 327 $aIntroduction -- Lipid bilayers -- Tat peptide -- Pb¢ ripple phase -- Structural and Material Perturbations of Lipid Bilayers Due to HIV-1 Tat Peptide -- Introduction -- Materials and Methods -- Analysis of Molecular Dynamics Simulation Data -- Results -- Discussion -- Conclusions -- Ripple Phase -- Introduction -- Materials and Methods -- LAXS Data Reduction -- Results for Fhk Form Factors -- Models to Fit the Fhk and Obtain the Phase Factors -- Electron Density Profiles and Coarse Grained Bilayer Structure -- nGIWAXS: Results -- tWAXS: Results -- Thin Rod Model -- Combining WAXS and LAXS Results for the Major Arm -- Discussion -- Conclusion -- Appendices. 330 $aThis Thesis in biological physics has two components, describing the use of X-ray scattering techniques to study the structure of two different stacked lipid membrane systems.  The first part focuses on the interaction between a short 11-mer peptide, Tat, which is part of the Tat protein in the HIV-1 virus.  Although highly positively charged, the Tat protein has been shown to translocate through hydrocarbon lipid bilayers easily, without requiring the cell?s energy, which is counter to its Born self-energy.  In this work Tat?s location in the headgroup region was demonstrated using a combined X-ray scattering and molecular dynamics approach.  Bilayer thinning was observed as well as softening of different membrane mimics due to Tat.  It was concluded that Tat?s headgroup location, which increases the area/lipid, and its bilayer softening likely reduce the energy barrier for passive translocation. The second part is a rigorous investigation of an enigmatic phase in the phase diagram of the lipid dimyristoylphosphatidylcholine (DMPC).  The ripple phase has fascinated many researchers in condensed matter physics and physical chemistry as an example of periodically modulated phases, with many theoretical and simulation papers published.  Despite systematic studies over the past three decades, molecular details of the structure were still lacking.  By obtaining the highest resolution X-ray data so far, this work revealed the complex nature of the chain packing, as well as confirming that the major side is thicker than the minor side of the saw-tooth ripple structure.  The new model shows that the chains in the major arm are tilted with respect to the bilayer normal and that the chains in the minor arm are slightly more disordered than all-trans gel-phase chains, i.e., the chains in the minor arm are more fluid-like.  This work provides the highest resolution X-ray structure of the ripple phase to-date. 410 0$aSpringer Theses, Recognizing Outstanding Ph.D. Research,$x2190-5053 606 $aBiophysics 606 $aBiological physics 606 $aCrystallography 606 $aCell membranes  606 $aPhysical chemistry 606 $aBiological and Medical Physics, Biophysics$3https://scigraph.springernature.com/ontologies/product-market-codes/P27008 606 $aCrystallography and Scattering Methods$3https://scigraph.springernature.com/ontologies/product-market-codes/P25056 606 $aMembrane Biology$3https://scigraph.springernature.com/ontologies/product-market-codes/L16050 606 $aPhysical Chemistry$3https://scigraph.springernature.com/ontologies/product-market-codes/C21001 615 0$aBiophysics. 615 0$aBiological physics. 615 0$aCrystallography. 615 0$aCell membranes . 615 0$aPhysical chemistry. 615 14$aBiological and Medical Physics, Biophysics. 615 24$aCrystallography and Scattering Methods. 615 24$aMembrane Biology. 615 24$aPhysical Chemistry. 676 $a574.875 700 $aAkabori$b Kiyotaka$4aut$4http://id.loc.gov/vocabulary/relators/aut$0792540 801 0$bMiAaPQ 801 1$bMiAaPQ 801 2$bMiAaPQ 906 $aBOOK 912 $a9910300403403321 996 $aStructure Determination of HIV-1 Tat$91772359 997 $aUNINA