Search results (51)
|First High-Resolution Structures of Antimicrobial Peptides Reveal Important Structural Features||
Structures of antimicrobial peptides piscidins 1 and 3 were solved in two bacterial cell mimics by oriented sample solid-state NMR. A significant finding of this work is that in contrast to the ideal structures shown in mechanistic studies of AMPs, the structures of both peptides are disrupted and kinked at a conserved central glycine, which results in stronger interactions with the lipid bilayers. The more pronounced imperfect amphipathicity of piscidin 1 over piscidin 3 that is revealed helps better understand why the former more effectively mixes the lipids as needed to induce the greatest damage to bacterial cells.
|Nucleotide-Induced Conformational Changes in Tetrameric GroEL Mapped by Hydrogen/Deuterium Exchange||
GroEL is a large (molecular weight ≈ 800,000) protein complex composed of two heptamers arranged like stacked doughnuts. By “spray-painting” the complex with heavy water, and then cutting into pieces with an enzyme and weighing the pieces, we are able to map the solvent accessibility throughout the complex, and observe conformational changes induced by binding of an analog of adenosine triphosphate (ATP), thereby illuminating the mechanism by which ATP activates the complex for its biological function.
|Dissolution DNP Polarizer for In Vivo 13C MRI||
The MagLab’s AMRIS facility has recently implemented dissolution DNP technology. The system utilizes a 5 T magnet in which samples are cooled to 14,000 gain in SNR on dissolution and injection into our 4.7T MRI/S scanner.
|Solid state NMR Structural Characterization of Oligomeric β-amyloid (1-42) Peptide||
Solid state NMR measurements reveal an important structural distinction between different disease-relevant aggregates: oligomers and fibrils. While molecular confirmations are similar within both structures, oligomers differ from fibrils in terms of intermolecular organization of beta-strands.
|In vivo Chlorine and Sodium MRI of Rat Brain at 21.1 T||
Using the lab’s 21 tesla magnet to image chlorine in the brain, researchers explore new ways to track tumor growth.
|Creating a Pseudo-Atomic Model of the COPII Cage||
Using a novel combination of techniques, scientists researching the COPII protein created a pseudo-atomic model of the COPII cage, gaining a better understanding of how its 96 subunits fit together.
|Topology of the Cell Metabolome by NMR||
Using a novel NMR approach, scientists characterize the metabolome of E. coli cells, determining 112 topologies of unique metabolites from a single sample.
|High-Frequency and -Field EPR Detection of a Di-radical Intermediate||
This work defines a new mechanism for radical-mediated catalysis of a protein substrate, and has broad implications for applied biocatalysis and for understanding oxidative protein modification during oxidative stress.
|Male and Female Mating Pheromones in Panagrellus redivivus||
Nematodes are the most abundant animal on earth, and they live in virtually every ecological niche on earth. Parasitic species have a significant health and economic impact through the infection of crops, domestic animals, and humans. Therefore, we are working to unravel the chemical language used by nematodes, with the ultimate goals of better understanding the role of small molecules in regulating behavior and of developing new approaches to control nematode parasites.
|High-Resolution MRI Probe for STRAFI Studies of Solid Material||
Magnetic resonance imaging (MRI) of solid materials entails numerous problems from short longitudinal relaxation (T2) times to requiring strong gradients to attain high resolution images. A promising technique to address these issues is the Stray Field Imaging (STRAFI) method.