In our study in @natcomms.nature.com we used #EPR #DEER #PELDOR spectroscopy with single subunit heterologous spin labelling and monitored the entire cap conformational ensemble of the human mechanosensitive TRAAK channel and showed it adopts two states in membranes.
www.nature.com/articles/s41...
TRAAK is expressed in the nervous system and helps regulate neuronal excitability. Here, the authors use EPR to quantify the relative populations of TRAAKâs swapped and non-swapped cap states in membr...
Our #openaccess work shows that P. fluorescens #Esterase is robust in crowded media and most divalent metals. But CuÂČâș and ZnÂČâș inhibit activity through aggregation. Insights into enzyme behavior in complex environments.
đ doi.org/10.1002/cbic...
#Biocatalysis #Enzymology
doi.org
âš New paper out in #JACS! We looked at the intrinsically disordered CTD tail of #Hsp90 often seen as a passive linker. Turns out, itâs not.
#StructuralBiology #Biophysics #EPR #NMR
pubs.acs.org/doi/10.1021/...
Angeliki Giannouli
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 electronâelectron 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 tailâCTD 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.
Proteinâpolymer conjugates: how do we understand their structure & dynamics? đŹOur new review highlights EPR spectroscopy+complementary techniques for insights in vitro & in cells.
Read more đ
www.sciencedirect.com/science/arti...
#ProteinPolymerConjugates #EPR #Biomaterials #PolymerScience
Angeliki Giannouli
Angeliki Giannouli
Protein-polymer conjugates (PPCs) are an important class of therapeutic macromolecules offering improvements in protein stability, circulation time, aâŠ
Just published đ: Binding Affinity Determines the Success of Endogenous CuII-NTA Spin Labeling for In-Cell Electron Paramagnetic Resonance Distance Measurements | The Journal of Physical Chemistry Letters @pubs.acs.org @ackermannkatrin.bsky.social pubs.acs.org/doi/10.1021/... #chemsky đ§Ș
pubs.acs.org
In-cell electron paramagnetic resonance (EPR) spectroscopy requires robust spin-labeling strategies compatible with cellular conditions. CuII-NTA coordination to genetically engineered double-histidin...
Work just published in @natcomms.nature.com rdcu.be/e9ieD demonstrating how pulse dipolar EPR can resolve different states of a human transporter in native membranes. EPR contributions by @ackermannkatrin.bsky.social @st-andrewschem.bsky.social
Great collaboration with @pliotasgroup.bsky.social and @yuemauom.bsky.social
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 TRAAKâs swapped...
