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Intrinsically disordered proteins (IDPs) are ubiquitously found in eukaryotic systems. Their lack of a well-defined structure suggests that their broad conformational ensemble is functionally advantageous. Here, we use single-molecule fluorescence resonance energy transfer (smFRET) to investigate the link between the polymer properties of one important IDP network system and the process of coupled binding and folding that leads to functional complexes. Our results suggest that the properties of the disordered IDP ensemble and the stability of the functional complexes are strongly correlated.

Thermodynamic considerations suggest correlation between efficient photo conversion and bright luminescence, in practice we do not usually see that. However, lead-halide perovskites do show excellent efficiencies in both photovoltaic and light-emitting applications. We study perovskite nanocrystals as a model system to further understand the origin of their enigmatic properties.
Low-dimensional colloidal nano-crystals of cesium lead halide demonstrate exceptionally bright emission without shelling and unusual room temperature transformation not common to other semiconductors nanocrystals. These properties suggest a near equilibrium nanocrystal system. In a series of studies we follow the formation and transformations of these nanocrystals. We can now grow quantum confined cesium lead halide nanocrystals with cube, plate and wire shapes and with atomic precision. We demonstrate how quantum confinement and dimensionality dictate the exciton behavior and photophysical properties of these crystals. In the case of two dimensional nanoplates we observe strong quantum confinement of the excitons.(1) In the case of nanowires we show that broken symmetry manifests in significant polarized emission. These nanowires can be further utilized through 3D printing and alignment process to fabricate highly polarized functional metamaterials. In addition to the synthetic shape control, further control of the optical properties is achieved by changing the anion composition. The “softness” of the perovskite crystal allows post synthetic room temperature transformations that tune the material band-gap values throughout the visible spectrum.(2-3) The resulting high quantum yield, combined with the synthetic versatility and facile transformations, position colloidal perovskites as a unique model system for the study of charge dynamics and thermodynamic transformations at the nanoscale, contributing to the understanding of next generation materials for energy. Future developments in perovskites, leading to more stable and lead free materials will also be discussed

To thermodynamically address quantum nanoscopic scenarios that involve very small heat sources and strong system-bath correlation, we suggest a new framework that is based on the principle of passivity. Passivity allows to get many thermodynamic inequalities that constrain observables that were so far outside the scope of thermodynamics. As an example we derive lower and upper bounds on the system-bath energy covariance in the Jaynes-Cummings model (spin-oscillator interaction). Using a stronger version of the passivity principle, we extend the second law to handle initial system-bath correlation (which is common in microscopic strong system-bath coupling scenarios). In addition, it is shown that passivity-based inequalities can detect "sub-Maxwellian” demons that apply a feedback that is too subtle to be detected using the standard second law. Finally an intrinsically quantum feature of strong passivity is exploited to assign a thermodynamic cost for quantum coherence generation.

Plants and apicomplexan parasites are more closely related than many might expect. Both evolved from a red algal ancestor and both still possess plastids. Plants have chloroplasts whereas apicomplexans like the malarial parasite Plasmodium falciparum have an apicoplast. This diminished ‘relic’ plastid is no longer photosynthetic, but remains essential for its production of isoprenoid precursors. Proof the apicoplast was of plant origin was provided, in part, by killing P. falciparum with herbicides. We recently turned this idea on its head asking whether drugs designed to treat malaria might be herbicidal and found many indeed were [1]. This has led us to apply the rapid advances in malaria research over the last decade to the stagnant field of herbicide discovery [2-3]. The success of glyphosate and spiralling cost of bringing new compounds to market stopped discovery programs by agrochemical companies and consequently, no new herbicide mode of action has reach the market in 20 years. Herbicide resistance has the world in a panic. Using antimalarial drug libraries and knowledge of malarial drug action we are attempting to put as many new modes of action ‘on the table’ as we can, each accompanied by an herbicidal molecule to probe each target [4]. A by-product of this applied work has already been knowledge about what, in many cases, are under-studied plant proteins [4].

[1] Corral, Leroux, Stubbs, Mylne (2017) Herbicidal properties of antimalarial drugs. Scientific Reports (PMID 28361906).
[2] Gandy, Corral, Mylne*, Stubbs* (2015) An interactive database to explore herbicide physicochemical properties. Org. Biomol. Chem. (PMID 25895669)
[3] Corral, Leroux, Tresch, Newton, Stubbs*, Mylne* (2017) Exploiting the evolutionary relationship between malarial parasites and plants to develop new herbicides. Angew. Chem. Int. Ed. Engl. (PMID 28654179)
[4] Various et al. (under review or in prep.) ... you have to come to find out more!

The replacement of fossil fuels by a clean and renewable energy source is one of the most urgent and challenging issues our society is facing today, which is why intense research is devoted to this topic recently. Nature has been using sunlight as the primary energy input to oxidize water and generate carbohydrates (a solar fuel) for over a billion years. Inspired, but not constrained, by nature, artificial systems [1] can be designed to capture light and oxidize water and reduce protons or other organic compounds to generate useful chemical fuels. In this context this contribution will present a variety of molecular water oxidation catalysts based on transition metal complexes, together with their activity in homogeneous phase and anchored on solid surfaces to generate electro- and photo-anodes. A detailed analysis of their performance will be discussed.