Doctoral Researcher (PhD) in Magnetic Resonance with Photo-Excited Molecules

jobs.ethz.ch

Binding Affinity Determines the Success of Endogenous CuII-NTA Spin Labeling for In-Cell Electron Paramagnetic Resonance Distance Measurements

In-cell electron paramagnetic resonance (EPR) spectroscopy requires robust spin-labeling strategies compatible with cellular conditions. CuII-NTA coordination to genetically engineered double-histidin...

doi.org

doi.org

Binding Affinity Determines the Success of Endogenous CuII-NTA Spin Labeling for In-Cell Electron Paramagnetic Resonance Distance Measurements

In-cell electron paramagnetic resonance (EPR) spectroscopy requires robust spin-labeling strategies compatible with cellular conditions. CuII-NTA coordination to genetically engineered double-histidin...

pubs.acs.org

Beyond a Passive Tether: Structural Insights into the Disordered Tail of Hsp90

The molecular chaperone Hsp90 is an abundant and essential homodimer that supports the stability and folding of hundreds of client proteins in cells. Its C-terminal domain (CTD) mediates dimerization and serves as a docking site for cochaperones bearing tetratricopeptide repeat (TPR) domains, which recognize the conserved MEEVD motif located at the end of an intrinsically disordered CTD tail. Despite its conservation, the structural role of this tail remains poorly understood. We investigated the conformational behavior of the yeast Hsp90 (yHsp90) CTD tail and its response to the binding of the TPR-containing PPIase cochaperone Cpr6. Using site-directed spin labeling with nitroxide and Gd(III) labels, we examined full-length yHsp90 (FL), isolated CTD (IsoC), and tail-truncated variants by double electron–electron resonance (DEER) and EPR spectroscopy. The CTD tails in IsoC and FL adopted distinct conformational ensembles, attributed to intramolecular interactions with the middle domain in FL. Cpr6 binding abolished these differences, indicating disruption of intramolecular tail contacts. In IsoC, the tail also stabilized an additional CTD conformation near the dimer interface that was absent in FL and was lost upon tail truncation, consistent with tail–CTD interactions observed by NMR. This population was reduced upon Cpr6 binding, shifting the IsoC conformational distribution toward that of FL. Additionally, this population was reduced in cellular environments and mimics. Together, our results demonstrate that the disordered CTD tail is an active structural element that modulates both its own conformational ensemble and CTD architecture, highlighting its potential functional relevance in the Hsp90 chaperone cycle.

pubs.acs.org

Crystallographic and EPR-based characterisation of Cu2+-binding to serum albumin: ATCUN coordination and additional sites

Copper homeostasis is essential for mammalian physiology. Serum albumin plays an important role in plasma copper transport and buffering, yet its Cu2+ binding sites have remained incompletely characte...

doi.org

Swapped and non-swapped TRAAK states co-exist in membranes at a ratio influenced by temperature

Nature Communications - TRAAK is expressed in the nervous system and helps regulate neuronal excitability. Here, the authors use EPR to quantify the relative populations of TRAAK’s swapped...

rdcu.be

Swapped and non-swapped TRAAK states co-exist in membranes at a ratio influenced by temperature - Nature Communications

TRAAK is expressed in the nervous system and helps regulate neuronal excitability. Here, the authors use EPR to quantify the relative populations of TRAAK’s swapped and non-swapped cap states in membr...

nature.com

Structural characterization and the role of EPR spectroscopy for protein–polymer conjugates

Protein-polymer conjugates (PPCs) are an important class of therapeutic macromolecules offering improvements in protein stability, circulation time, a…

sciencedirect.com

biorxiv.org

Careers

germancareers-bruker.icims.com

Chiral molecular 4f qubits by post functionalization

We herein demonstrate the synthesis of a pair of enantiomerically pure YbIII complexes by post-functionalisation of the parent YbIII complex via condensation with an enantiomerically pure chiral amine...

doi.org

Toward Generalized Solution-State 1H DNP NMR via Particle-Mediated Cross-Relaxation

This study discusses a potential route for enhancing 1H NMR signals in the liquid phase at high magnetic fields for samples on the 100 μL volume scale using dynamic nuclear polarization (DNP). The approach involves dispersing an inert powder that is both rich in protons and capable of undergoing DNP with good efficiency at noncryogenic temperatures, and letting the solid 1H polarization thus enhanced pass from the dispersed particles onto the surrounding liquid via spontaneous cross relaxation effects. To this end, BDPA-doped polystyrene (PS) particles in the μm range were suspended in 30 μL of heptane, loaded into 3.2 mm sapphire rotors, and spun at ≈500 Hz for homogeneity purposes in a 14.1 T magnet. Irradiation with ≈13 W at 395 GHz while maintaining temperature in the 185–220 K range thus enhanced the PS proton polarization ≈12-fold within ≈2 s; after ca. 6 s of irradiation, this resulted in ca. 3-fold enhancements of the heptane proton resonances, while preserving their ≤2 Hz line widths. The conditions over which such particle-mediated transfer occurs were explored over a range of sample composition, deuteration and molecular weight; best results were obtained when polarizing a ball-milled powder made of deuterated-PS/PS/BDPA = 86.4/9.6/4.0 suspended on perdeuterated heptane-d16. While the solution-state enhancements provided by this approach are still relatively modest, its generality could open new avenues in DNP-enhanced 1H NMR that do not sacrifice on the volumes, on the high-resolution conditions, or on the multiscan averaging that is customary in contemporary applications.

pubs.acs.org

Broad substrate scope C-C oxidation in cyclodipeptides catalysed by a flavin-dependent filament - Nature Communications

Cyclodipeptide oxidases are filamentous enzymes. Here, the authors dissect the mechanism of a promiscuous flavoenzyme from the biosynthesis of cyclodipeptide natural products, unveiling fast catalysis...

doi.org

Lecturer in Organic Chemistry - AC2577LS at University of St Andrews

An academic position as a Lecturer in Organic Chemistry - AC2577LS is being advertised on jobs.ac.uk. Click now to find more details and explore additional academic job opportunities.

jobs.ac.uk

University of Reading proposes closing its chemistry department next year

The university joins several others that are considering the future of their departments and undergraduate programmes

chemistryworld.com