Peculiarities of Emulsions Stabilized by Stimuli-Responsive Interpenetrating Polymeric Network Microgels.

Emulsions have become a crucial product form in various industries in modern times. Expanding the class of substances used to stabilize emulsions can improve their stability or introduce new properties. Particularly, the use of stimuli-responsive microgels makes it possible to create "smart" emulsions whose stability can be controlled by changing any of the specified stimuli.

Interactions of Nucleosomes with Acidic Patch-Binding Peptides: A Combined Structural Bioinformatics, Molecular Modeling, Fluorescence Polarization, and Single-Molecule FRET Study.

In eukaryotic organisms, genomic DNA associates with histone proteins to form nucleosomes. Nucleosomes provide a basis for genome compaction, epigenetic markup, and mediate interactions of nuclear proteins with their target DNA loci. A negatively charged (acidic) patch located on the H2A-H2B histone dimer is a characteristic feature of the nucleosomal surface.

Micromorphology of the leaf surface in some species of Dryadoideae (Rosaceae).

The leaf surface of 5 species of the subfamily Dryadoideae (Rosaceae) was studied for the first time by cryoscanning electron microscopy. In the studied representatives of Dryadoideae, some signs of micromorphology were found that are characteristic of other Rosaceae. In Dryas drummondii and D.

Swift Janitor: Efficient Absorption of a Minor Component from the Mixtures of Immiscible Liquids by Thermoresponsive Macroscopic and Microscopic Hydrogels.

Polymer hydrogels are known to be efficient absorbents of various aqueous solutions. Along with the hydrophilicity of the polymer network, the presence of specific functional groups is required for the absorption of respective solutes. Alternatively, a selective uptake can be realized without any specific attraction of solutes to the network, which is shown in this paper.

Behavior of PNIPAM Microgels in Different Organic Solvents.

In this research, we studied, in detail, the behavior of common PNIPAM microgels, obtained through surfactant-free precipitation polymerization, in a number of organic solvents. We showed that many of the selected solvents serve as good solvents for the PNIPAM microgels and that the size and architecture of the microgels depend on the solvent chosen. Expanding the range of solvents used for PNIPAM microgel incubation greatly enhances the possible routes for microparticle functionalization and modification, as well as the encapsulation of water-insoluble species.

Antiseptic Materials on the Base of Polymer Interpenetrating Networks Microgels and Benzalkonium Chloride.

Polymer microgels, including those based on interpenetrating networks (IPNs), are currently vastly studied, and their practical applications are a matter of thriving research. In this work, we show the perspective for the use of polyelectrolyte IPN microgels either as scavengers or carriers of antiseptic substances. Here, we report that poly--isopropylacrylamide/polyacrylic acid IPN microgels can efficiently absorb the common bactericidal and virucidal compound benzalkonium chloride.

Histone dynamics mediate DNA unwrapping and sliding in nucleosomes.

Nucleosomes are elementary building blocks of chromatin in eukaryotes. They tightly wrap ∼147 DNA base pairs around an octamer of histone proteins. How nucleosome structural dynamics affect genome functioning is not completely clear.

Linking chromatin composition and structural dynamics at the nucleosome level.

Nucleosomes are fundamental units of chromatin compaction, which organize ∼200 DNA base pairs using an octamer of histone proteins. Their ubiquitous presence in the cell nucleus since the first eukaryotes compelled the chromatin machinery to coevolve and learn how to exploit various modes of nucleosome dynamics and sense differences in nucleosome composition. Alterations to histone or DNA sequences, post-translational modifications (PTM) of histones, recruitment of chromatin proteins modulate nucleosome dyn amics and provide epigenetic regulation to the DNA processing pathways (transcription, replication, repair, etc.

Structural interpretation of DNA-protein hydroxyl-radical footprinting experiments with high resolution using HYDROID.

Hydroxyl-radical footprinting (HRF) is a powerful method for probing structures of nucleic acid-protein complexes with single-nucleotide resolution in solution. To tap the full quantitative potential of HRF, we describe a protocol, hydroxyl-radical footprinting interpretation for DNA (HYDROID), to quantify HRF data and integrate them with atomistic structural models. The stages of the HYDROID protocol are extraction of the lane profiles from gel images, quantification of the DNA cleavage frequency at each nucleotide and theoretical estimation of the DNA cleavage frequency from atomistic structural models, followed by comparison of experimental and theoretical results.

[Combined effect of zeatin and hydrogen peroxide on growth of rape and tomato germs as applied to the conditions of biological life support systems].

Cytokine-regulated growth of germs' roots and hypocotyls was investigated on a background of modeled oxidative outbreak caused by the stress from exogenous hydrogen peroxide. Germs of rape (1-d old) and tomato (56-d old) in Petri dishes with solutions containing substances under study were subjected to 24-48 hour incubation in the dark. Exogenous zeatin inhibited growth; in different tests treatment with H2O2 brought about both acceleration and inhibition of root and hypocotyl growth.

[Polyphase character of the dependence of Brassica napus germ root and hypocotyl growth on zeatin and thidiazuron concentrations with view of applicability to biological life support systems].

Physiologically active substances are considered as a potential component of plant cultivation technologies for biological life support systems. In spacelight, plant reactions to growth-regulating agents may be changed by the specific stress factors such as microgravity, radiation, and trace admixtures in cabin air. Complex character of the concentration dependence of PAS efficiency and consequent variability generate a need to optimize plant growth regulating technologies in order to stabilize the wanted effect.

Investigation of physical-chemical properties of agarose hydrogels with embedded emulsions.

Composite agarose hydrogels with embedded tetradecane emulsions stabilized by cetylpyridinium chloride were studied. The absorption efficiency of 4-nitrophenyl ethers of carbonic acids by the composite agarose gels increases with the length of the hydrocarbon tail of the ester. The diffusion rate of amphiphilic substances in the composite gels was demonstrated to be much less that than in the standard agarose gels.

Intelligent gels and cryogels with entrapped emulsions.

Smart thermoresponsive gels and cryogels with incorporated emulsions have been synthesized and studied. The gels were obtained by three-dimensional copolymerization of N-isopropylacrylamide and N,N'-methylene-bis-acrylamide or N,N'-bis(acryloyl)cystamine in the presence of dispersion of tetradecane stabilized with sodium dodecylsulfate. Polymerization was performed at room temperature and below the water crystallization temperature.

[Effect of the medium composition on the accumulation of 2-keto-D-gluconic acid in Pseudomonas putida cultures].

The effect of the composition of the culture medium and the age of the culture on the activities of the enzymes involved in accumulation of 2-ketogluconic acid by Pseudomonas putida was studied. The activities of glucose and gluconate dehydrogenases that are responsible for direct oxidation of glucose to 2-ketogluconic acid, were 2-3 times higher during the active growth of the culture than in the stationary phase. The activities of 2-ketogluconokinase and 2-keto-6-phosphogluconate reductase, enzymes converting 2-ketogluconic acid, increased 2-4-fold on the glucose exhausting.

[Alcohol oxidation by Candida guilliermondii yeasts grown on hexadecanol].

A number of enzyme systems involved in the first steps of hexadecane oxidation can be induced by hexadecanol, an intermediate product of hexadecane degradation. It has also been found that, in Candida guilliermondii cells and in their mitochondrial fraction, an oxidase system is induced when the cells are grown on hexadecanol. This system is similar to that in cells grown on hexadecane; it oxidises higher alcohols at a high rate and is not inhibited by the inhibitors of the man phosphorylating respiration chain.

[Octanol oxidation by the mitochondria of Torulopsis candida].

Octanol oxidation by the mitochondria of Torulopsis candida grown on hexadecane was studied. Octanol oxidation involves an enzyme system labile to heating but resistant to the main inhibitors of the phosphorylating respiration chain. When octanol is oxidized in aerobic conditions, cytochrome b is reduced, with the absorption maxima in alpha, beta and gamma bands being at 555, 526 and 425 nm, respectively.

[Formation of antibiotic 2562 by a culture of the actinomycete, Streptomyces griseovariabilis].

An actinomycetous culture 2562 inhibiting the growth of gramnegative bacteria was isolated from a soil sample. The culture was classified as Streptomyces griseovariabilis. It was found that culture 2562 produced an antibiotic belonging to the group of novobiocin.

[New species of the genus Nocardia and its antibiotic properties].

A culture of a new species of Nocardia, i.e. N.

[Formation of a new antibiotic, nocamycin, by a culture of Nocardiopsis syringae sp. nov].

A culture of a new actinomycetous species, Nocardiopsis syrinage was isolated from a soil sample. The antibiotic produced by it was named nocamycin. It accumulated in the culture fluid on cultivation of the organism in a nutrient medium containing soybean meal, glycerin, sodium chloride and calcium carbonate.

[Effect of aeration conditions on the biosynthesis of carminomycin by an actinomadura carminata culture].

The effect of the aeration rate on biosynthesis of carminomycin by Actinomadura carminata and biochemical changes in the fermentation broth on the use of 3 complex media of different composition was studied. The carminomycin-producing organism can grow and produce the antibiotic within the ranges of the aeration changes from 0.98 to 18.