The use of FRET in the analysis of motor protein structure

Luciferase-Based Biosensors in the Era of the COVID-19 Pandemic

Luciferase-based biosensors have a wide range of applications and assay formats, including their relatively recent use in the study of viruses. Split luciferase, bioluminescence resonance energy transfer, circularly permuted luciferase, cyclic luciferase, and dual luciferase systems have all been used to interrogate the structure and function of prominent viruses infecting humans, animals, and plants. The utility of these assays is demonstrated by numerous studies which have not only successfully characterized interactions between viral and host cell proteins but that have also used these systems to identify viral inhibitors. In the present COVID-19 pandemic, luciferase-based biosensors are already playing a critical role in the study of the culprit virus SARS-CoV-2 as well as in the development of serological assays and drug development via high-throughput screening. In this review paper, we provide a summary of existing luciferase-based biosensors and their applications in virology.

Optimization of a Bioluminescence Resonance Energy Transfer-Based Assay for Screening of Trypanosoma cruzi Protein/Protein Interaction Inhibitors

Chagas disease, a parasitic disease caused by Trypanosoma cruzi, is a major public health burden in poor rural populations of Central and South America and a serious emerging threat outside the endemic region, since the number of infections in non-endemic countries continues to rise. In order to develop more efficient anti-trypanosomal treatments to replace the outdated therapies, new molecular targets need to be explored and new drugs discovered. Trypanosoma cruzi has distinctive structural and functional characteristics with respect to the human host. These exclusive features could emerge as interesting drug targets. In this work, essential and differential protein-protein interactions for the parasite, including the ribosomal P proteins and proteins involved in mRNA processing, were evaluated in a bioluminescence resonance energy transfer-based assay as a starting point for drug screening. Suitable conditions to consider using this simple and robust methodology to screening compounds and natural extracts able to inhibit protein-protein interactions were set in living cells and lysates.

Experimental and theoretical investigation of the distance dependence of localized surface plasmon coupled Förster resonance energy transfer

The distance dependence of localized surface plasmon (LSP) coupled Förster resonance energy transfer (FRET) is experimentally and theoretically investigated using a trilayer structure composed of separated monolayers of donor and acceptor quantum dots with an intermediate Au nanoparticle layer. The dependence of the energy transfer efficiency, rate, and characteristic distance, as well as the enhancement of the acceptor emission, on the separations between the three constituent layers is examined. A d(-4) dependence of the energy transfer rate is observed for LSP-coupled FRET between the donor and acceptor planes with the increased energy transfer range described by an enhanced Förster radius. The conventional FRET rate also follows a d(-4) dependence in this geometry. The conditions under which this distance dependence is valid for LSP-coupled FRET are theoretically investigated. The influence of the placement of the intermediate Au NP is investigated, and it is shown that donor-plasmon coupling has a greater influence on the characteristic energy transfer range in this LSP-coupled FRET system. The LSP-enhanced Förster radius is dependent on the Au nanoparticle concentration. The potential to tune the characteristic energy transfer distance has implications for applications in nanophotonic devices or sensors.

Role of computational methods in pharmaceutical sciences

Over the past two decades computational methods have eased up the financial and experimental burden of early drug discovery process. The in silico methods have provided support in terms of databases, data mining of large genomes, network analysis, systems biology on the bioinformatics front and structure-activity relationship, similarity analysis, docking, and pharmacophore methods for lead design and optimization. This review highlights some of the applications of bioinformatics and chemoinformatics methods that have enriched the field of drug discovery. In addition, the review also provided insights into the use of free energy perturbation methods for efficiently computing binding energy. These in silico methods are complementary and can be easily integrated into the traditional in vitro and in vivo methods to test pharmacological hypothesis.

FRET enhancement in multilayer core-shell nanoparticles

This study describes the preparation and characterization of novel multilayer core-shell nanoparticles displaying metal-enhanced Forster resonant energy transfer. The increase in range and efficiency of Forster resonant energy transfer in these fluorescent nanocomposites and their vastly improved luminosity make them promising optical probes for a variety of applications such as cell imaging and biosensing.