To assess the daily distribution of temporal resolution in visual detection, binocular double-pulse resolution (DPR) was measured over a 24 h period in six healthy subjects. DPR showed a significant daily variation with an amplitude for the foveal stimulus of up to 60%. Like in other vigilance-dependent daily rhythms, optimal performance occurred around midday. The DPR measurements described he...

Helicases are molecular motors that separate DNA strands for efficient replication of genomes. We probed the kinetics of individual ring-shaped T7 helicase molecules as they unwound double-stranded DNA (dsDNA) or translocated on single-stranded DNA (ssDNA). A distinctive DNA sequence dependence was observed in the unwinding rate that correlated with the local DNA unzipping energy landscape. The...

Stoichiometry of molecular complexes plays a crucial role in biology. Moreover, for quantitative fluorescence studies, it is often useful to know the number of fluorophores labeled onto the molecules studied. In this work, we propose an approach to determine the number of independent fluorescence emitters on fluorescent molecules based on fluorescence blinking caused by photo-induced triplet st...

The exonucleolytic degradation of high-density labeled DNA by exonuclease III was monitored using two-color fluorescence correlation spectroscopy (FCS). One strand of the double stranded template DNA was labeled on either one or two base types and additionally at one end via a 5' Cy5 tagged primer. Exonucleolytic degradation was followed via the diffusion time, the brightness of the remaining D...

in this study, the interaction of the anthracycline antibiotic doxorubicin with dna-hmg 1 complex was investigated employing uv/vis spectroscopy, thermal denaturation and dna cellulose chromatography techniques. the results indicated that the binding of doxorubicin to the protein reduces its tm in a dose dependent manner. although doxorubicin protects free dna against thermal denaturation in th...

Synthetic linear SARS-CoV-2 RNA fragments (ssRNA) and a double-stranded DNA plasmid harbouring the nucleocapsid (N) gene are evaluated in four different VTM for up to 10 freeze–thaw cycles by qRT-PCR following magnetic bead extraction.

For the isolation of single stranded plasmid DNA, various E. coli and E. coli-Streptomyces shuttle plasmids were equipped with the phage f1 replication origin. The transformation of some representative Streptomyces species with plasmid vectors occurred irrespective of whether single or double stranded DNA was used. In contrast, the transformation of Streptomyces was 10 to 100 times more efficie...

gene delivery might be affected by several tribulations based on carrier/vector applied. bacteriophages lambda and m13 have different genome conformations; linear double-stranded and circular single-stranded respectively. therefore, it might be expected that these two common classes of gene delivery vehicles will have different capacity for gene delivery and expression in eukaryote cells. to ad...

The wormlike chain model describes the micromechanics of semiflexible polymers by introducing the persistence length. We propose a method of measuring the persistence length of DNA in a controllable near-native environment. Using a dark field microscope, the projected positions of a gold nanoparticle undergoing constrained Brownian motion are captured. The nanoparticle is tethered to a substrat...