Effect of Chemical Chaperones on the Stability of Proteins during Heat- or Freeze-Thaw Stress.

The importance of studying the structural stability of proteins is determined by the structure-function relationship. Protein stability is influenced by many factors among which are freeze-thaw and thermal stresses. The effect of trehalose, betaine, sorbitol and 2-hydroxypropyl-β-cyclodextrin (HPCD) on the stability and aggregation of bovine liver glutamate dehydrogenase (GDH) upon heating at 50 °C or freeze-thawing was studied by dynamic light scattering, differential scanning calorimetry, analytical ultracentrifugation and circular dichroism spectroscopy.

Pyrrolo[2,3-]indazole as a novel chemotype for both influenza A virus and pneumococcal neuraminidase inhibitors.

Influenza infections are often exacerbated by secondary bacterial infections, primarily caused by . Both respiratory pathogens have neuraminidases that support infection. Therefore, we hypothesized that dual inhibitors of viral and bacterial neuraminidases might be an advantageous strategy for treating seasonal and pandemic influenza pneumonia complicated by bacterial infections.

Ways of Long-Term Survival of Hydrocarbon-Oxidizing Bacteria in a New Biocomposite Material-Silanol-Humate Gel.

Immobilized bacterial cells are presently widely used in the development of bacterial preparations for the bioremediation of contaminated environmental objects. Oil hydrocarbons are among the most abundant pollutants. We have previously described a new biocomposite material containing hydrocarbon-oxidizing bacteria (HOB) embedded in silanol-humate gels (SHG) based on humates and aminopropyltriethoxysilane (APTES); high viable cell titer was maintained in this material for at least 12 months.

Multiscale Simulations of the Covalent Inhibition of the SARS-CoV-2 Main Protease: Four Compounds and Three Reaction Mechanisms.

We report the results of computational modeling of the reactions of the SARS-CoV-2 main protease (M) with four potential covalent inhibitors. Two of them, carmofur and nirmatrelvir, have shown experimentally the ability to inhibit M. Two other compounds, X77A and X77C, were designed computationally in this work.

Assessing the Differential Methylation Analysis Quality for Microarray and NGS Platforms.

Differential methylation (DM) is actively recruited in different types of fundamental and translational studies. Currently, microarray- and NGS-based approaches for methylation analysis are the most widely used with multiple statistical models designed to extract differential methylation signatures. The benchmarking of DM models is challenging due to the absence of gold standard data.

DFT potentials from a chemical perspective: Anatomy of electron (de)localization in molecules and crystals.

We introduce a fermionic potential, , as a comprehensive measure of electron (de)localization in atomic-molecular systems. Unlike other common descriptors as ELF, LOL, etc., it characterizes all physical effects responsible for (de)localization of electrons, namely: an exchange hole depth, its tendency to change, a sensitivity of an exchange correlation hidden in a pair density and kinetic potential to local variations in electron density.

Distortion of Population Statistics due to the Use of Different Methodological Approaches to the Construction of Genomic DNA Libraries.

Several different methods of DNA library preparation for paleogenetic studies are now available. However, the chemical reactions underlying each of them can affect the primary sequence of ancient DNA (aDNA) in the libraries and taint the results of a statistical analysis. In this paper, we compare the results of a sequencing of the aDNA libraries of a Bronze Age sample from burials of the Caucasian burial ground Klady, prepared using three different approaches: (1) shotgun sequencing, (2) strategies for selecting target genomic regions, and (3) strategies for selecting target genomic regions, including DNA pre-treatment with a mixture of uracil-DNA glycosylase (UDG) and endonuclease VIII.

Speeding up SDS-PAGE: Theory and experiment.

In order to accelerate Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), here we propose an optimized version of the technique enabled by experimental tuning reinforced by theoretical description. In the resulting system, the gel buffer was diluted twofold and supplemented with glycine at a low concentration, whereas a higher voltage was applied. This approach reduced runtime from 90 to 18 min.

Hypobiosis of Mycobacteria: Biochemical Aspects.

Under suboptimal growth conditions, bacteria can transit to the dormant forms characterized by a significantly reduced metabolic activity, resistance to various stress factors, and absence of cell proliferation. Traditionally, the dormant state is associated with the formation of highly differentiated cysts and spores. However, non-spore-forming bacteria can transfer to the dormant-like hypobiotic state with the generation of less differentiated cyst-like forms (which are different from spores).

Comparative effect of conductive and dielectric materials on methanogenesis from highly concentrated volatile fatty acids.

Various conductive materials and their dielectric counterparts were used to get deeper insights into contribution of direct interspecies electron transfer (DIET) in improving methanogenesis from highly concentrated volatile fatty acids (12.5 g/L). Potential CH yield, maximum CH production rate and lag phase were significantly (up to 1.

Electrophoretic Assembly of Antibody-Antigen Complexes Facilitates 1000 Times Improvement in the Limit of Detection of Serological Paper-Based Assay.

Serological assays detect the presence of specific antibodies in blood. There are urgent and important applications for serological point-of-care (POC) assays. However, available detection methods are either insufficiently sensitive or too complex for POC settings.

C-Type Natriuretic Peptide Acts as a Microorganism-Activated Regulator of the Skin Commensals and in Dual-Species Biofilms.

The effect of C-type natriuretic peptide in a concentration closer to the normal level in human blood plasma was studied on the mono-species and dual-species biofilms of the skin commensal bacteria HL043PA2 and ATCC14990. Despite the marginal effect of the hormone on cutibacteria in mono-species biofilms, the presence of staphylococci in the community resulted in a global shift of the CNP effect, which appeared to increase the competitive properties of , its proliferation and the metabolic activity of the community. was mostly inhibited in the presence of CNP.

Simultaneous addition of CO-nanobubble water and iron nanoparticles to enhance methane production from anaerobic digestion of corn straw.

In this research, CO-nanobubble water (CO-NBW) and iron nanoparticles (FeNPs) were added simultaneously to exploit individual advantages to enhance the methanogenesis process from both the stability of anaerobic digestion (AD) system and the activity of anaerobic microorganism aspects. Results showed that the AD performance was enhanced by supplementing with CO-NBW or FeNPs individually, and could be further improved by simultaneous addition of the two additives. The maximum methane yield was achieved in the CO-NBW + FeNPs reactor (141.

Biochemical hydrogen potential assay for predicting the patterns of the kinetics of semi-continuous dark fermentation.

The performance and kinetics response of thermophilic semi-continuous dark fermentation (DF) of simulated complex carbohydrate-rich waste was investigated at various hydraulic retention times (HRT) (2, 2.5, and 3 d) and compared with data obtained from biochemical hydrogen potential assay (BHP). A culture of Thermoanaerobacterium thermosaccharolyticum was used as the inoculum and dominated both in BHP and semi-continuous reactor.

Food Freshness Measurements and Product Distinguishing by a Portable Electronic Nose Based on Organic Field-Effect Transistors.

Determination of food freshness, which is the most ancient role of the human sense of smell, is still a challenge for compact and inexpensive electronic nose devices. Fast, sensitive, and reusable sensors are long-awaited in the food industry to replace slow, labor-intensive, and expensive bacteriological methods. In this work, we present microbiological verification of a novel approach to food quality monitoring and spoilage detection using an electronic nose based on organic field-effect transistors (OFETs) and its application for distinguishing products.

Bioinformatics-Structural Approach to the Search for New D-Amino Acid Oxidases.

D-amino acid oxidase (DAAO, EC 1.2.1.

High-Level Production of Soluble Cross-Reacting Material 197 in Cytoplasm Due to Fine Tuning of the Target Gene's mRNA Structure.

Cross-reacting material 197 (CRM197) is a non-toxic mutant of the diphtheria toxin and is widely used as a carrier protein in conjugate vaccines. This protein was first obtained from the supernatant of the mutant strain. This pathogenic bacteria strain is characterized by a slow growth rate and a relatively low target protein yield, resulting in high production costs for CRM197.

Evolution of Ceftriaxone Resistance of Penicillin-Binding Proteins 2 Revealed by Molecular Modeling.

Penicillin-binding proteins 2 (PBP2) are critically important enzymes in the formation of the bacterial cell wall. Inhibition of PBP2 is utilized in the treatment of various diseases, including gonorrhea. Ceftriaxone is the only drug used to treat gonorrhea currently, and recent growth in PBP2 resistance to this antibiotic is a serious threat to human health.

Antituberculosis Macozinone Extended-Release Tablets To Enhance Bioavailability: a Pilot Pharmacokinetic Study in Beagle Dogs.

Macozinone (MCZ; PBTZ169) is a first-in-class antituberculosis clinical-stage benzothiazinone-based drug candidate. Although its efficacy and safety have been strongly proven in several preclinical and clinical studies, the physicochemical and pharmacokinetic properties specific to MCZ required further optimization. Accordingly, this study aimed to evaluate the pharmacokinetics of MCZ administered as extended-release (ER) tablets F2 and F6 compared to immediate-release (IR) dispersible tablets for oral suspension.

Effects of Molecular Crowding and Betaine on HSPB5 Interactions, with Target Proteins Differing in the Quaternary Structure and Aggregation Mechanism.

The aggregation of intracellular proteins may be enhanced under stress. The expression of heat-shock proteins (HSPs) and the accumulation of osmolytes are among the cellular protective mechanisms in these conditions. In addition, one should remember that the cell environment is highly crowded.

[CRISPR Interference in Regulation of Bacterial Gene Expression].

The review is devoted to the use of the CRISPR/Cas system for obtaining knockdowns of target bacterial genes by CRISPR-mediated interference (CRISPRi). CRISPRi is based on the preservation of the ability of the inactivated dCas nuclease in complex with guide RNA to bind a target, which leads to reversible repression of the selected genes. The review describes the principle of operation of CRISPR/Cas and CRIS-PRi/dCas and provides examples of various approaches to the use of CRISPRi with the most popular inactivated nucleases dCas9 and dCas12a.

Single substitution in α-helix of active center enhanced thermostability of Aspergillus awamori exo-inulinase.

Exo-inulinases are applied in inulin hydrolysis and production of feed additives and need to be stable at temperatures of 60-95 °C. Aspergillus awamori exo-inulinase Inu1 is considerably thermostable, with a T of 73.2 °C.

Electrophoresis-Assisted Multilayer Assembly of Nanoparticles for Sensitive Lateral Flow Immunoassay.

Lateral flow immunoassay (LFIA) is a rapid, simple, and inexpensive point-of-need method. A major limitation of LFIA is a high limit of detection (LOD), which impacts its diagnostic sensitivity. To overcome this limitation, we introduce a signal-enhancement procedure that is performed after completing LFIA and involves controllably moving biotin- and streptavidin-functionalized gold nanoparticles by electrophoresis.

Dependence of the content of starch and reducing sugars on the level of expression of the genes of β-amylases StBAM1 and StBAM9 and the amylase inhibitor StAI during long-term low-temperature storage of potato tubers.

Solanum tuberosum L. is the most important non-grain starch crop with a potential yield of 38-48 t/ha and a starch content of 13.2-18.

Influence of the Active Site Flexibility on the Efficiency of Substrate Activation in the Active Sites of Bi-Zinc Metallo-β-Lactamases.

The influence of the active site flexibility on the efficiency of catalytic reaction is studied by taking two members of metallo-β-lactamases, L1 and NDM-1, with the same substrate, imipenem. Active sites of these proteins are covered by L10 loops, and differences in their amino acid compositions affect their rigidity. A more flexible loop in the NDM-1 brings additional flexibility to the active site in the ES complex.