Biocompatible, industrially scalable, and opto/electrochemically active biomaterials are promising for biosensor platform design and application. Herein, cyclic oligosaccharide, β-cyclodextrin (BCD), is conjugated with Butein, a chalcone-type polyphenol, via dehydration reaction of the hydroxyl groups of BCD and the benzoyl ring of Butein. Functional group changes in the conjugated BCD-Butein were comprehensively studied using UV-visible absorbance, Fourier transform-infrared, and X-ray photoelectron spectroscopic techniques.
View Article and Find Full Text PDFHybridizing biomolecules with metal oxide nanostructures possessing inherent optical emission and electrochemical functionality is advantageous for external mediator-free analytical applications. This work demonstrates the ultrasonochemical synthesis of hafnium oxide (HfO) nanoparticles and their combination with butein, a chalcone type polyphenol, for the direct electrochemical detection of active herbaceuticals. The underlying hybridization chemistry between HfO and butein within the bio-nano interface is comprehensively investigated using ultraviolet diffuse reflectance, X-ray diffraction, Fourier-transform infrared, and X-ray photoelectron spectroscopic techniques.
View Article and Find Full Text PDFRNA-binding proteins (RBPs) represent a large family of proteins with an extensive array of roles that contribute to coordinating and directing multiple functions in RNA metabolism and transcription [...
View Article and Find Full Text PDFElevated levels of reactive oxygen species (ROS) reduce replication fork velocity by causing dissociation of the TIMELESS-TIPIN complex from the replisome. Here, we show that ROS generated by exposure of human cells to the ribonucleotide reductase inhibitor hydroxyurea (HU) promote replication fork reversal in a manner dependent on active transcription and formation of co-transcriptional RNA:DNA hybrids (R-loops). The frequency of R-loop-dependent fork stalling events is also increased after TIMELESS depletion or a partial inhibition of replicative DNA polymerases by aphidicolin, suggesting that this phenomenon is due to a global replication slowdown.
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