Protein nanoparticles with ligand-binding and enzymatic activities.

Purpose: To develop a general method for NP fabrication from various proteins with maintenance of biological activity.

Methods: A novel general approach for producing protein nanoparticles (NP) by nanoprecipitation of the protein solutions in 1,1,1,3,3,3-hexafluoroisopropanol is described. Protein NP sizes and shapes were analyzed by dynamic light scattering, scanning electron and atomic force microscopy (SEM and AFM).

Polymorphism of G4 associates: from stacks to wires via interlocks.

We examined the assembly of DNA G-quadruplexes (G4s) into higher-order structures using atomic force microscopy, optical and electrophoretic methods, NMR spectroscopy and molecular modeling. Our results suggest that parallel blunt-ended G4s with single-nucleotide or modified loops may form different types of multimers, ranging from stacks of intramolecular structures and/or interlocked dimers and trimers to wires. Decreasing the annealing rate and increasing salt or oligonucleotide concentrations shifted the equilibrium from intramolecular G4s to higher-order structures.

i-Clamp phenoxazine for the fine tuning of DNA i-motif stability.

Non-canonical DNA structures are widely used for regulation of gene expression, in DNA nanotechnology and for the development of new DNA-based sensors. I-motifs (iMs) are two intercalated parallel duplexes that are held together by hemiprotonated C-C base pairs. Previously, iMs were used as an accurate sensor for intracellular pH measurements.

Corrigendum: Interaction of Toxin with Outer Membrane Vesicles Reveals New Mechanism of Its Secretion and Delivery.

[This corrects the article on p. 2 in vol. 7, PMID: 28144586.

Interaction of Toxin with Outer Membrane Vesicles Reveals New Mechanism of Its Secretion and Delivery.

The only recognized virulence factor of enterotoxigenic (ETBF) that accompanies bloodstream infections is the zinc-dependent non-lethal metalloprotease toxin (BFT). The isolated toxin stimulates intestinal secretion, resulting in epithelial damage and necrosis. Numerous publications have focused on the interrelation of BFT with intestinal inflammation and colorectal neoplasia, but nothing is known about the mechanism of its secretion and delivery to host cells.