Remote control of charge transport and chiral induction along a DNA-metallohelicate

Revisiting recent unusual drug-DNA complex structures: Implications for cancer and neurological disease diagnostics and therapeutics

DNA plays a crucial role in various biological processes such as protein production, replication, recombination etc. by adopting different conformations. Targeting these conformations by small molecules is not only important for disease therapy, but also improves our understanding of the mechanisms of disease development. In this review, we provide an overview of some of the most recent ligand-DNA complexes that have diagnostic and therapeutic applications in neurological diseases caused by abnormal repeat expansions and in cancer associated with mismatches. In addition, we have discussed important implications of ligands targeting higher-order structures, such as four-way junctions, G-quadruplexes and triplexes for drug discovery and DNA nanotechnology. We provide an overview of the results and perspectives of such structural studies on ligand-DNA interactions.

Recent Advances in Agglomeration Detection and Dual-Function Application of Surface-Enhanced Raman Scattering (SERS)

Surface-enhanced Raman scattering (SERS) has been widely utilized in early detection of disease biomarkers, cell imaging, and trace contamination detection, owing to its ultra-high sensitivity. However, it is also subject to certain application restrictions in virtue of its expensive detection equipment and long-term stability of SERS-active substrate. Recently, great progress has been made in SERS technology, represented by agglomeration method. Dual readout signal detection methods are combined with SERS, including electrochemical detection, fluorescence detection, etc., establishing a new fantastic viewpoint for application of SERS. In this review, we have made a comprehensive report on development of agglomeration detection and dual-function detection methods based on SERS. The synthesis methods for plasmonic materials and mainstream SERS enhancement mechanism are also summarized. Finally, the key facing challenges are discussed and prospects are addressed.

Tuning DNA Supramolecular Polymers by the Addition of Small, Functionalized Nucleobase Mimics

Nucleobase mimicking small molecules able to reconfigure DNA are a recently discovered strategy that promises to extend the structural and functional diversity of nucleic acids. However, only simple, unfunctionalized molecules such as cyanuric acid and melamine have so far been used in this approach. In this work, we show that the addition of substituted cyanuric acid molecules can successfully program polyadenine strands to assemble into supramolecular fibers. Unlike conventional DNA nanostructure functionalization, which typically end-labels DNA strands, our approach incorporates functional groups into DNA with high density using small molecules and results in new DNA triple helices coated with alkylamine or alcohol units that grow into micrometer-long fibers. We find that small changes in the small molecule functional group can result in large structural and energetic variation in the overall assembly. A combination of circular dichroism, atomic force microscopy, molecular dynamics simulations, and a new thermodynamic method, transient equilibrium mapping, elucidated the molecular factors behind these large changes. In particular, we identify substantial DNA sugar and phosphate group deformations to accommodate a hydrogen bond between the phosphate and the small-molecule functional groups, as well as a critical chain length of the functional group which switches this interaction from intra- to interfiber. These parameters allow the controlled formation of hierarchical, hybrid DNA assemblies simply through the addition and variation of small, functionalized molecules.

Phosphorus Compounds of Natural Origin: Prebiotic, Stereochemistry, Application

Organophosphorus compounds play a vital role as nucleic acids, nucleotide coenzymes, metabolic intermediates and are involved in many biochemical processes. They are part of DNA, RNA, ATP and a number of important biological elements of living organisms. Synthetic compounds of this class have found practical application as agrochemicals, pharmaceuticals, bioregulators, and othrs. In recent years, a large number of phosphorus compounds containing P-O, P-N, P-C bonds have been isolated from natural sources. Many of them have shown interesting biological properties and have become the objects of intensive scientific research. Most of these compounds contain asymmetric centers, the absolute configurations of which have a significant effect on the biological properties of the products of their transformations. This area of research on natural phosphorus compounds is still little-studied, that prompted us to analyze and discuss it in our review. Moreover natural organophosphorus compounds represent interesting models for the development of new biologically active compounds, and a number of promising drugs and agrochemicals have already been obtained on their basis. The review also discusses the history of the development of ideas about the role of organophosphorus compounds and stereochemistry in the origin of life on Earth, starting from the prebiotic period, that allows us in a new way to consider this most important problem of fundamental science.