Structural analysis of hERG channel blockers and the implications for drug design.

The repolarizing current (I) produced by the hERG potassium channel forms a major component of the cardiac action potential and blocking this current by small molecule drugs can lead to life-threatening cardiotoxicity. Understanding the mechanisms of drug-mediated hERG inhibition is essential to develop a second generation of safe drugs, with minimal cardiotoxic effects. Although various computational tools and drug design guidelines have been developed to avoid binding of drugs to the hERG pore domain, there are many other aspects that are still open for investigation.

Copper (0) Mediated Single Electron Transfer-Living Radical Polymerization of Methyl Methacrylate: Functionalized Graphene as a Convenient Tool for Radical Initiator.

Polymer nanocomposites have been synthesized by the covalent addition of bromide-functionalized graphene (Graphene-Br) through the single electron transfer-living radical polymerization technique (SET-LRP). Graphite functionalized with bromide for the first time via an efficient route using mild reagents has been designed to develop a graphene based radical initiator. The efficiency of sacrificial initiator (ethyl α-bromoisobutyrate) has also been compared with a graphene based initiator towards monitoring their Cu(0) mediated controlled molecular weight and morphological structures through mass spectroscopy (MOLDI-TOF) and field emission scanning electron microscopy (FE-SEM) analysis, respectively.

An experimental and steered molecular dynamics simulation approach to histidine assisted liquid-phase exfoliation of graphite into few-layer graphene.

A simple and green approach to exfoliate graphite in water was developed by its reaction with an amino acid, histidine (His), resulting in the spatial expansion of the interlayer space. Subsequent sonication led to few-layered nanosheets of graphene in water. Steered molecular dynamics (MD) simulations revealed that the exfoliating graphene sheet underwent sheered motion before completely scaling off from the other layer.

Protein Arrangement Effects on the Exciton Dynamics in the PE555 Complex.

The environmental coupling of the phycobiliprotein antenna complex PE555 and its excitonic energy transfer mechanisms are studied in detail. Molecular dynamics simulations were performed followed by calculations of the vertical transition energies along the classical ground-state trajectory. To this end, the distributions of energy levels for the PE555 complex were found to be similar to those of the PE545 complex despite the clear differences in the respective protein structures.

Relation between Dephasing Time and Energy Gap Fluctuations in Biomolecular Systems.

Excitation energy and charge transfer are fundamental processes in biological systems. Because of their quantum nature, the effect of dephasing on these processes is of interest especially when trying to understand their efficiency. Moreover, recent experiments have shown quantum coherences in such systems.

Influence of Force Fields and Quantum Chemistry Approach on Spectral Densities of BChl a in Solution and in FMO Proteins.

Studies on light-harvesting (LH) systems have attracted much attention after the finding of long-lived quantum coherences in the exciton dynamics of the Fenna-Matthews-Olson (FMO) complex. In this complex, excitation energy transfer occurs between the bacteriochlorophyll a (BChl a) pigments. Two quantum mechanics/molecular mechanics (QM/MM) studies, each with a different force-field and quantum chemistry approach, reported different excitation energy distributions for the FMO complex.