We report the complete solid-state MAS NMR resonance assignment of a medium-sized, trimeric membrane protein, YadA-M. The protein YadA (Yersinia adhesin A) is an important virulence factor of enteropathogenic Yersinia species (such as Yersinia enterocolitica and Yersinia pseudotuberculosis). YadA is localized on the bacterial cell surface and is involved in adhesion to host cells and tissues. It is anchored in the outer membrane by a transmembrane anchor domain (YadA-M). This domain hosts the so-called autotransporter function of YadA: it transports its own N-terminal domain through the outer membrane. The assignment is based on a dataset that consisted of several MAS NMR correlation spectra, recorded on a single, uniformly (13)C, (15)N- labelled microcrystalline preparation. Except for the single C-terminal residue and the mobile strep tag, we were able to completely assign YadA-M. From this, secondary structure elements were predicted, which, combined with several long-range interstrand restraints, yielded the architecture of the β-sheet.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3495290 | PMC |
http://dx.doi.org/10.1038/srep00803 | DOI Listing |
Polymers (Basel)
December 2024
Institute of Chemistry, Federal University of Uberlândia, Uberlândia 38400-902, Brazil.
Cellulose tosylate (MCC-Tos) is a key derivative for surface modification and a crucial precursor for cellulose compatibilization in click reactions, enabling its functionalization for advanced applications. Replacing tosyl groups with alkyne groups broadens cellulose's potential in biocompatible reactions, such as thiol-yne click chemistry and protein/enzyme immobilization. To achieve this, we optimized the heterogeneous synthesis of MCC-Tos using a Doehlert matrix statistical design, evaluating the influence and interaction of the reaction conditions.
View Article and Find Full Text PDFJ Magn Reson
December 2024
Oral Product Development, Pharmaceutical Technology & Development, Operations, AstraZeneca, Gothenburg, Sweden.
A new 3.2 mm H-F-X magic angle spinning dynamic nuclear polarization NMR (MAS DNP-NMR) probe was developed with a unique coil design with separate radiofrequency channels for H excitation and C or F detection to enable acquisition of H-F cross-polarization (CP) MAS experiments, direct-detected F spectra with proton decoupling, and acquisition on C with simultaneous double decoupling on the H and 19F channels as well as H-F-C double-CP experiments under low temperature MAS DNP conditions. We use these sequences to study AZD2811, which is an active pharmaceutical ingredient (API), in its pure dry state as well as in its corresponding drug delivery formulation consisting of drug-loaded polymeric nanoparticles (PNPs).
View Article and Find Full Text PDFChem Sci
January 2025
Materials Science and Engineering Program, The Graduate School, Florida State University 2005 Levy Ave. Tallahassee FL 32310 USA
Solid electrolytes (SEs) are crucial for advancing next-generation rechargeable battery technologies, but their commercial viability is partially limited by expensive precursors, unscalable synthesis, or low ionic conductivity. Lithium tetrahaloaluminates offer an economical option but exhibit low Li conductivities with high activation energy barriers. This study reports the synthesis of lithium aluminum chalcohalide (LiAlClS) using inexpensive precursors one-step mechanochemical milling.
View Article and Find Full Text PDFJ Phys Chem Lett
January 2025
National High Magnetic Field Laboratory, Florida State University, 1800 E. Paul Dirac Dr, Tallahassee, Florida 32310, United States.
The contribution of protons in or near biradical polarizing agents in Dynamic Nuclear Polarization (DNP) has recently been under scrutiny. Results from selective deuteration and simulations have previously suggested that the role of protons in the biradical molecule depends on the strength of the electron-electron coupling. Here we use the cross effect DNP mechanism to identify and acquire H solid-state NMR spectra of the protons that contribute to propagation of the hyperpolarization, via an experimental approach dubbed Nuclear-Nuclear Double Resonance (NUDOR).
View Article and Find Full Text PDFStroke
January 2025
Population Health Research Institute, University of British Columbia, Vancouver, Canada. (M.A.S., J.W.E., A.H.K., A. Shoamanesh, A.T., R.G.H., A.C., R.Z.).
Background: Stroke secondary to intracranial atherosclerotic disease (ICAD) is associated with high recurrence risk despite currently available secondary prevention strategies. In patients with systemic atherosclerosis, a significant reduction of stroke risk with no increase in intracranial or fatal hemorrhage was seen when rivaroxaban 2.5 mg twice daily was added to aspirin.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!