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Research Highlights

Chemistry Department Research Highlights

Li group and collaborators publish emissive supramolecules in Nature Communications

>> February 8, 2018

Coordination-driven self-assembly has emerged as a powerful bottom-up approach to construct various supramolecular architectures with increasing complexity and functionality. Dr. Li and his collaborators constructed a series of supramolecular materials with precisely-controlled rosettes-like structures. Such supramolecules display tunable emissive properties with respect to different generations, particularly, pure white-light emission.

Li Group Nature Communications
Self-assembled supramolecules with rosette-like structures

Dr. Xiaopeng Li, Assistant Professor in the Chemistry Department at USF, reports the self-assembly of three generations of giant supramolecules with rosettes-like structures. Such supramolecules display tunable emissive properties with respect to different generations, particularly, pure white-light emission. His Nature Communications paper entitled "Self-assembly of emissive supramolecular rosettes with increasing complexity using multitopic terpyridine ligands" was published this February.

Most traditional fluorophores only exhibit emission in dilute solution but not in aggregation state due to aggregation caused quenching (ACQ) phenomenon. Dr. Li and his team introduced two levels of restrictions to minimize the intramolecular rotation through elaborate molecular design. They obtained strong emissive supramolecular materials in both solution and aggregation states. Another striking discovery is that G2 exhibited highly pure white light emission property under a wide range of good/poor solvents ratios. The single-component white light emitter is expected to exhibit superior performance improved stability, good reproducibility, and simple device fabrication procedure compared to those multi-component emitters. The team eventually named those structures as supramolecular rosettes, and hopefully, they can give out a bright light in both supramolecular chemistry and emissive materials community to inspire us to seek more complicated structures with tunable properties. The team was also invited by Nature Communications to write a story Behind the Paper.


Gelis group and collaborators publish ground-breaking paper on Hsp90 in Nature Communications

>> January 26, 2018

Dr. Ioannis Gelis, Assistant Professor in the Chemistry Department at USF, reports a ground-breaking study on the Hsp90 chaperone. His Nature Communications paper entitled "Phosphorylation induced cochaperone unfolding promotes kinase recruitment and client class-specific Hsp90 phosphorylation" was published this January. The study shows how phosphorylation controls the timely progression of the critical Hsp90 machinery through different steps of the chaperone cycle and resulted in a more complete understanding of its mechanism, which will aid cancer drug development.

Gelis group Nature Communications
Prof. Ioannis Gelis and graduate student Ashleigh Bachman

Hsp90 is important for cancer and helps other proteins fold. It needs the Cdc37 cochaperone to mediate folding of protein kinases, in a cycle regulated by phosphorylation. Using high field NMR, the Gelis lab showed that phosphorylation of Cdc37 results in partial unfolding of Cdc37. The unfolding did not affect Cdc37 association with the machinery, but revealed a SH2 domain binding motif, which recruited other kinases to subsequently phosphorylate Hsp90. The latter phosphorylation caused dissociation of Cdc37 from the Hsp90 complex, without affecting the interaction with other cochaperones. Aspects of the study were validated by cellular experiments in collaboration with Dr. Len Neckers' group from the National Cancer Institute at NIH, and computer simulations by Dr. Arjan van der Vaart's group in the Chemistry Department at USF.