國立虎尾科技大學 |

Structure Determination of HIV-1 Tat/Fluid Phase Membranes and DMPC Ripple Phase Using X-Ray Scattering

Record Type:	Language materials, printed : Monograph/item
Title/Author:	Structure Determination of HIV-1 Tat/Fluid Phase Membranes and DMPC Ripple Phase Using X-Ray Scattering/ by Kiyotaka Akabori.
Author:	Akabori, Kiyotaka.
Description:	XX, 168 p. 114 illus., 89 illus. in color.online resource. :
Contained By:	Springer Nature eBook
Subject:	Biophysics. -
Online resource:	https://doi.org/10.1007/978-3-319-22210-3
ISBN:	9783319222103

Structure Determination of HIV-1 Tat/Fluid Phase Membranes and DMPC Ripple Phase Using X-Ray Scattering
Akabori, Kiyotaka.

Structure Determination of HIV-1 Tat/Fluid Phase Membranes and DMPC Ripple Phase Using X-Ray Scattering[electronic resource] /by Kiyotaka Akabori. - 1st ed. 2015. - XX, 168 p. 114 illus., 89 illus. in color.online resource. - Springer Theses, Recognizing Outstanding Ph.D. Research,2190-5053. - Springer Theses, Recognizing Outstanding Ph.D. Research,.

Introduction -- 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.

This 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.

ISBN: 9783319222103

Standard No.: 10.1007/978-3-319-22210-3doiSubjects--Topical Terms:

581576
Biophysics.

LC Class. No.: QH505

Dewey Class. No.: 571.4

Structure Determination of HIV-1 Tat/Fluid Phase Membranes and DMPC Ripple Phase Using X-Ray Scattering
LDR:04126nam a22004215i 4500 001 959995
003 DE-He213
005 20200706083308.0
007 cr nn 008mamaa
008 201211s2015 gw | s |||| 0|eng d
020 $a 9783319222103 $9 978-3-319-22210-3
024 7 $a 10.1007/978-3-319-22210-3 $2 doi
035 $a 978-3-319-22210-3
050 4 $a QH505
072 7 $a PHVN $2 bicssc
072 7 $a SCI009000 $2 bisacsh
072 7 $a PHVN $2 thema
072 7 $a PHVD $2 thema
082 0 4 $a 571.4 $2 23
100 1 $a Akabori, Kiyotaka. $4 aut $4 http://id.loc.gov/vocabulary/relators/aut $3 1070148
245 1 0 $a Structure Determination of HIV-1 Tat/Fluid Phase Membranes and DMPC Ripple Phase Using X-Ray Scattering $h [electronic resource] / $c by Kiyotaka Akabori.
250 $a 1st ed. 2015.
264 1 $a Cham : $b Springer International Publishing : $b Imprint: Springer, $c 2015.
300 $a XX, 168 p. 114 illus., 89 illus. in color. $b online resource.
336 $a text $b txt $2 rdacontent
337 $a computer $b c $2 rdamedia
338 $a online resource $b cr $2 rdacarrier
347 $a text file $b PDF $2 rda
490 1 $a Springer Theses, Recognizing Outstanding Ph.D. Research, $x 2190-5053
505 0 $a Introduction -- 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.
520 $a This 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.
650 0 $a Biophysics. $3 581576
650 0 $a Biological physics. $3 1253579
650 0 $a Crystallography. $3 583281
650 0 $a Cell membranes . $3 1253580
650 0 $a Physical chemistry. $3 1148725
650 1 4 $a Biological and Medical Physics, Biophysics. $3 1113305
650 2 4 $a Crystallography and Scattering Methods. $3 1142947
650 2 4 $a Membrane Biology. $3 783465
650 2 4 $a Physical Chemistry. $3 668972
710 2 $a SpringerLink (Online service) $3 593884
773 0 $t Springer Nature eBook
776 0 8 $i Printed edition: $z 9783319222097
776 0 8 $i Printed edition: $z 9783319222110
776 0 8 $i Printed edition: $z 9783319370477
830 0 $a Springer Theses, Recognizing Outstanding Ph.D. Research, $x 2190-5053 $3 1253569
856 4 0 $u https://doi.org/10.1007/978-3-319-22210-3
912 $a ZDB-2-PHA
912 $a ZDB-2-SXP
950 $a Physics and Astronomy (SpringerNature-11651)
950 $a Physics and Astronomy (R0) (SpringerNature-43715)