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

Nonfiction, Science & Nature, Science, Chemistry, Crystallography, Biological Sciences, Biophysics
Cover of the book Structure Determination of HIV-1 Tat/Fluid Phase Membranes and DMPC Ripple Phase Using X-Ray Scattering by Kiyotaka Akabori, Springer International Publishing
View on Amazon View on AbeBooks View on Kobo View on B.Depository View on eBay View on Walmart
Author: Kiyotaka Akabori ISBN: 9783319222103
Publisher: Springer International Publishing Publication: October 20, 2015
Imprint: Springer Language: English
Author: Kiyotaka Akabori
ISBN: 9783319222103
Publisher: Springer International Publishing
Publication: October 20, 2015
Imprint: Springer
Language: English

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.

View on Amazon View on AbeBooks View on Kobo View on B.Depository View on eBay View on Walmart

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.

More books from Springer International Publishing

Cover of the book Descriptional Complexity of Formal Systems by Kiyotaka Akabori
Cover of the book Theoretical and Empirical Studies on Cooperatives by Kiyotaka Akabori
Cover of the book Portfolio Selection Using Multi-Objective Optimisation by Kiyotaka Akabori
Cover of the book Pervasive Computing Paradigms for Mental Health by Kiyotaka Akabori
Cover of the book Psychology of Bilingualism by Kiyotaka Akabori
Cover of the book Urban Transformations in Rio de Janeiro by Kiyotaka Akabori
Cover of the book Advances in Mathematics Education Research on Proof and Proving by Kiyotaka Akabori
Cover of the book Technology, Commercialization and Gender by Kiyotaka Akabori
Cover of the book Reviews of Environmental Contamination and Toxicology Volume 236 by Kiyotaka Akabori
Cover of the book Development of an Ultrasonic Sensing Technique to Measure Lubricant Viscosity in Engine Journal Bearing In-Situ by Kiyotaka Akabori
Cover of the book Intelligent Natural Language Processing: Trends and Applications by Kiyotaka Akabori
Cover of the book The Dynamics of Transculturality by Kiyotaka Akabori
Cover of the book Image and Graphics by Kiyotaka Akabori
Cover of the book Foundations and Practice of Security by Kiyotaka Akabori
Cover of the book Common Complications in Endodontics by Kiyotaka Akabori
We use our own "cookies" and third party cookies to improve services and to see statistical information. By using this website, you agree to our Privacy Policy