Two dimensional infrared four wave mixing spectroscopy of simple molecules, peptides and proteins PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Two dimensional infrared four wave mixing spectroscopy of simple molecules, peptides and proteins PDF full book. Access full book title Two dimensional infrared four wave mixing spectroscopy of simple molecules, peptides and proteins by Paul Murray Donaldson. Download full books in PDF and EPUB format.
Author: Paul Murray Donaldson
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Author: Paul Murray Donaldson
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Author: Paul Murray Donaldson
Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Get Book Here
Book Description
Author: Yukihiro Ozaki
Publisher: Academic Press
ISBN: 0128186119
Category : Science
Languages : en
Pages : 609
Get Book Here
Book Description
Vibrational Spectroscopy in Protein Research offers a thorough discussion of vibrational spectroscopy in protein research, providing researchers with clear, practical guidance on methods employed, areas of application, and modes of analysis. With chapter contributions from international leaders in the field, the book addresses basic principles of vibrational spectroscopy in protein research, instrumentation and technologies available, sampling methods, quantitative analysis, origin of group frequencies, and qualitative interpretation. In addition to discussing vibrational spectroscopy for the analysis of purified proteins, chapter authors also examine its use in studying complex protein systems, including protein aggregates, fibrous proteins, membrane proteins and protein assemblies. Emphasis throughout the book is placed on applications in human tissue, cell development, and disease analysis, with chapters dedicated to studies of molecular changes that occur during disease progression, as well as identifying changes in tissues and cells in disease studies. Provides thorough guidance in implementing cutting-edge vibrational spectroscopic methods from international leaders in the field Emphasizes in vivo, in situ and non-invasive analysis of proteins in biomedical and life science research more broadly Contains chapters that address vibrational spectroscopy for the study of simple purified proteins and protein aggregates, fibrous proteins, membrane proteins and protein assemblies
Author: Lauren P. DeFlores
Publisher:
ISBN:
Category :
Languages : en
Pages : 238
Get Book Here
Book Description
The amide II' diagonal provides a measure of the degree of exchange and the cross peaks between the structurally sensitive amide I/I' vibration and the solvent exposure sensitive amide II and II' modes reveal the location of exchange. Partial exchange of the secondary structure of ubiquitin is revealed by correlation of the different amide signatures through analysis of cross peak line shapes, positions and amplitudes. Results provide direct evidence for a highly stable helix and labile "--Sheet structure.
Author: Huong Tran Kratochvil
Publisher:
ISBN:
Category :
Languages : en
Pages : 231
Get Book Here
Book Description
Understanding the structure and dynamics of proteins is essential to understanding their roles and functions in these physiological processes. In this thesis, I describe the implementation of an ultrafast nonlinear spectroscopic technique, two-dimensional infrared (2D IR) spectroscopy to probe the structure and dynamics of ion channels and amyloid fibers. Regarding ion channels, I describe the combination of semisynthesis, 2D IR spectroscopy and molecular dynamic (MD) simulations in addressing the longstanding question of ion permeation through the selectivity filter of a potassium ion channel. I show that ions and water alternate through the filter and that these ions cannot occupy adjacent binding sites. Furthermore, 2D IR experiments revealed a flipped state that is predicted by MD simulations but not observed in x-ray crystallography. In another aspect of this work, we show that the collapsed state of the filter is structurally different in low K+ and low pH. Moreover, our work also reveals how the large conformational motions of the protein are coupled to structural changes in the selectivity filter, as evidenced by a change in the ion occupancy. In a second research direction, I developed an optical technique to quantify photoactivatable fluorophores with fluorescence microscopy. This technique allows for the quantification of a limitless number of fluorophores, and corrects for stochastic events such as fluorescence intermittency. This work can be extended to the study of amyloids, where determining the number of proteins in a prefibrillar aggregates is necessary for understanding their roles in amyloid related diseases. Finally, using 2D IR spectroscopy we describe the effect of common solvents on the anharmonicity of small molecule chromophores. The data indicates that the carbonyl anharmonicity, and, subsequently, the Stark tuning rate, is an intrinsic property of the carbonyl vibrational probes, which have important implications on the interpretation of carbonyl vibrational frequency shifts in the condensed phase.
Author: Yuan Feng
Publisher:
ISBN: 9781321448368
Category :
Languages : en
Pages : 130
Get Book Here
Book Description
Femtosecond two-dimensional infrared spectroscopy in combination with isotope labeling and molecular dynamics simulation has been used to investigate the structures and dynamics of nonfolding peptides and collagen peptides. Homopolymeric peptides are simple yet important, serve as model systems for investigating the intrinsic propensity of protein folding, especially for those disordered or unfolded peptides in aqueous solution. Here the full structure of (Ala)5 has been studied. Two different isotope-labeled peptides, Ala-(13C)Ala-(13C,18O)Ala-Ala-Ala, and Ala-Ala-(13C,18O)Ala-(13C)Ala-Ala were strategically designed to simplify the four-oscillator system into three two-oscillator systems. By utilizing the different polarization dependence of diagonal and cross peaks, coupling constant β and angle θ between transition dipoles has been extracted through spectral fitting. The coupling constant is around 4 cm-1 and angle around 100. These parameters were related to the dihedral angles characterizing the peptide backbone structure through DFT calculated maps. The derived dihedrals are all located in the polyproline-II region. These results were compared to the conformations sampled by hamiltonian replica-exchange MD simulation with 3 different CHARMM force fields: C22, C36 and Drude. The C22 force field predicted too high α-helix population, whereas C36 predicted that polyproline-II is the dominate conformation, consistent with experimental findings. The Drude model predicted dominating beta-sheet. Since the 2D-IR derived results were obtained from fitting to a single set of structural parameters, the effect of structural fluctuation within one conformation and structural transition between different conformations was also discussed. The C36 MD trajectories were used to simulate 2D IR spectra using the sum-over-state method and the time-averaging approximation (TAA) method. Reasonable agreement with the experimental data was achieved. Collagen is the most abundant protein in mammal. Its structural properties are important for biological functions. Here, the structure and thermal melting of a model collagen peptide, (PPG)10, has been investigated. The temperature dependent linear IR spectra of the unlabeled peptide and two isotopomers (either 13C-16O or 13C-18O labeled on the 4th glycine residue) showed that the triple helix unravels with increasing temperature and leads to greater solvent exposure. With some adjustments of calculation parameters according to linear IR spectra, 2D IR spectral simulation based on MD trajectories and TAA reasonably reproduced experimental spectra taken at the parallel and perpendicular polarization conditions. Further refinement of models and parameters are needed to improve the simulation. Our results for model nonfolding peptides and collagen peptides contribute to the fundamental understanding of peptide structure and dynamics, and to the further development of theoretical models for simulating 2D IR spectra.
Author: Ayanjeet Ghosh
Publisher:
ISBN:
Category :
Languages : en
Pages : 285
Get Book Here
Book Description
Author: Nicholas K. Preketes
Publisher:
ISBN: 9781303603662
Category :
Languages : en
Pages : 152
Get Book Here
Book Description
Simulations of two-dimensional infrared (2DIR) spectroscopy of several proteins are presented. Applications of 2DIR spectroscopy to protein folding, protein aggregation, and photosensing are reported. We demonstrate that 2DIR spectroscopy is an excellent probe of protein structure and dynamics. Our simulations predict future experiments as well as provide detailed explanations of previous experiments. We also present simulations of the related two-dimensional ultraviolet and two-dimensional stimulated resonance Raman spectroscopies, which are shown to provide complementary information to 2DIR spectroscopy. This thesis can be viewed as a guide for the design and analysis of future two-dimensional optical measurements on proteins.
Author: Fouad Husseini
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Author: Erin Rose Birdsall
Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Get Book Here
Book Description
Proteins and peptides associated with cell membranes play a vital role in cell signaling and cell health. From ion channels that allow cells to transduce electrical signals to antibiotic peptides that break open cell membranes, membrane-associated and membrane-bound proteins are of interest due to their importance. However, due to the nature of lipid membranes, the ion channels and other membrane proteins have historically been more challenging to study since they cannot be simply in aqueous solution like soluble proteins. Increased knowledge of protein expression and purification in the last few decades has made membrane-associated and membrane-bound proteins and peptides more readily studied, however, there is still much to learn about the basic function of these macromolecules. For example, one of the most fundamental processes is ion channel conduction. In potassium channels, potassium ions flow at nearly the diffusion limit with exquisite selectivity when the channel is open. The previously established mechanism for ion transduction has been recently called into question. Two-dimensional infrared spectroscopy is an excellent method to study membrane-bound proteins and peptides because of its structural sensitivity, inherent time resolution, and ability to be modeled from structural and computational results. In this dissertation, methods with which to study potassium channels, as well as other membrane-bound peptides are developed, along with strategies to study surfaces, including working with proteins bound in a single lipid bilayer. First, a voltage and pH-sensitive antimicrobial peptide is studied using surface-enhanced 2D IR spectroscopy and an applied voltage. Since the peptide is in a bilayer tethered to a surface, the sample is no longer isotropic and relative intensities of spectral peaks allowed for the extraction of insertion angles upon a change in pH and a change in voltage. Insertion angles were determined through modeling the spectra based on the peptide structure and helical coupling values. Next, progress to studying the selectivity filter of two potassium channels is outlined, including experiment looking at an ester label in the selectivity filter. The ester label causes a water pocket in the ion channel to collapse and changes the binding sites for ions in the selectivity filter. Using waiting time analysis, the dynamics of the labeled residue can be measured. Finally advances to polarization controls to distinguish bulk and surface signals is theoretically developed to create a surface specific spectroscopy. Finally, a chapter is included to disseminate the work presented in this dissertation to the public.
