Molecular Basis of Influence of A501X Mutations in Penicillin-Binding Protein 2 of Strain 35/02 on Ceftriaxone Resistance.

The increase in the resistance of mutant strains of to the antibiotic ceftriaxone is pronounced in the decrease in the second-order acylation rate constant, k/K, by penicillin-binding protein 2 (PBP2). These changes can be caused by both the decrease in the acylation rate constant, k, and the weakening of the binding affinity, i.e.

The novel drug candidate VOMG kills Mycobacterium abscessus and other pathogens by inhibiting cell division.

Aims: The incidence of lung infections is increasing worldwide in individuals suffering from cystic fibrosis and chronic obstructive pulmonary disease. Mycobacterium abscessus is associated with chronic lung deterioration in these populations. The intrinsic resistance of M.

Saturation Mutagenesis and Molecular Modeling: The Impact of Methionine 182 Substitutions on the Stability of β-Lactamase TEM-1.

Serine β-lactamase TEM-1 is the first β-lactamase discovered and is still common in Gram-negative pathogens resistant to β-lactam antibiotics. It hydrolyzes penicillins and cephalosporins of early generations. Some of the emerging TEM-1 variants with one or several amino acid substitutions have even broader substrate specificity and resistance to known covalent inhibitors.

Polyamines putrescine and spermidine as modulators of protein aggregation rate: The effect on DTT-induced aggregation of α-lactalbumin.

Protein aggregation is undesirable for cells due to its possible toxicity, and is also undesirable in biotechnology and pharmaceuticals. Polyamines are known to be capable of both suppressing and stimulating protein aggregation. In the present work polyamines (spermidine, putrescine) have been shown to alter the pathway of α-lactalbumin aggregation induced by dithiothreitol, leading to the formation of larger protein particles during the initial stages of aggregation and promoting the later stage of sticking of aggregates.

Single-point substitution F97M leads to in cellulo crystallization of the biphotochromic protein moxSAASoti.

To enhance the photoconversion performance of biphotochromic moxSAASoti protein, a substitution F97 M was introduced. In addition to enhancing the target properties, this substitution also resulted in the crystallization of the recombinant protein within living HeLa cells (also referred to as in cellulo crystallization). The phenomenon of protein crystallization in living cells is not unique, yet the mechanisms and application of in cellulo crystallization remain significant for further research.

A highly specific aptamer for the SARS-CoV-2 spike protein from the authentic strain.

DNA aptamers are oligonucleotides that specifically bind to target molecules, similar to how antibodies bind to antigens. We identified an aptamer named MEZ that is highly specific to the receptor-binding domain, RBD, of the SARS-CoV-2 spike protein from the Wuhan-Hu-1 strain. The SELEX procedure was utilized to enrich the initial 31-mer oligonucleotide library with the target aptamer.

Metagenomic evidence of a novel anammox community in a cold aquifer with high nitrogen pollution.

The process of anaerobic ammonium oxidation by nitrite (anammox) is a globally essential part of N cycle. To date, 8 Candidatus genera and more than 22 species of anammox bacteria have been discovered in various anthropogenic and natural habitats, including nitrogen-polluted aquifers. In this work, anammox bacteria were detected for the first time in the groundwater ecosystem with high anthropogenic nitrogen pollution (up to 1760 mg NO-N/L and 280 mg NH-N/L) and low year-round temperature (7-8 °C) in the zone of a uranium sludge repository.

Proteomic and transcriptomic analyses of biofilms and planktonic cultures in presence of epinephrine.

Transcriptomic and proteomic analysis were performed on 72 h biofilms of the acneic strain and planktonic cultures in the presence of epinephrine. Epinephrine predominantly downregulated genes associated with various transporter proteins. No correlation was found between proteomic and transcriptomic profiles.

Enhanced thermophilic high-solids anaerobic digestion of organic fraction of municipal solid waste with spatial separation from conductive materials in a single reactor volume.

Despite benefits such as lower water and working volume requirements, thermophilic high solids anaerobic digestion (THSAD) often fails due to the rapid build-up of volatile fatty acids (VFAs) and the associated drop in pH. Use of conductive materials (CM) can promote THSAD through stimulation of direct interspecies electron transfer (DIET), while the need for their constant dosing due to poor separation from effluent impairs economic feasibility. This study used an approach of spatially separating magnetite and granular activated carbon (GAC) from the organic fraction of municipal solid waste (OFMSW) in a single reactor for THSAD.

Efficacy of macozinone in mice with genetically diverse susceptibility to Mycobacterium tuberculosis infection.

Host heterogeneity in pulmonary tuberculosis leads to varied responses to infection and drug treatment. The present portfolio of anti-TB drugs needs to be boosted with new drugs and drug regimens. Macozinone, a clinical-stage molecule targeting the essential enzyme, DprE1, represents an attractive option.

Modulating mycobacterial envelope integrity for antibiotic synergy with benzothiazoles.

Developing effective tuberculosis drugs is hindered by mycobacteria's intrinsic antibiotic resistance because of their impermeable cell envelope. Using benzothiazole compounds, we aimed to increase mycobacterial cell envelope permeability and weaken the defenses of , serving as a model for Initial hit, BT-08, significantly boosted ethidium bromide uptake, indicating enhanced membrane permeability. It also demonstrated efficacy in the -zebrafish embryo infection model and -infected macrophages.

Role of phosphate-coordinating arginine residues in the thermal stability of uridine phosphorylase from Shewanella oneidensis MR-1.

The role of phosphate-coordinating arginine residues in the thermal stability of uridine phosphorylase from Shewanella oneidensis MR-1 was investigated by mutation analysis. Uridine phosphorylase mutant genes were constructed by site-directed mutagenesis. The enzyme mutants were prepared and isolated, and their kinetic parameters were determined.

Nanobubble technology to enhance energy recovery from anaerobic digestion of organic solid wastes: Potential mechanisms and recent advancements.

Nanobubble (NB) technology has gained popularity in the environmental field owing to its distinctive characteristics and ecological safety. More recently, the application of NB technology in anaerobic digestion (AD) systems has been proven to promote substrate degradation and boost the production of biogas (H and/or CH). This review presents the recent advancements in the application of NB technology in AD systems.

The role of the correlated motion(s) of the chromophore in photoswitching of green and red forms of the photoconvertible fluorescent protein mSAASoti.

Wild-type SAASoti and its monomeric variant mSAASoti can undergo phototransformations, including reversible photoswitching of the green form to a nonfluorescent state and irreversible green-to-red photoconversion. In this study, we extend the photochemistry of mSAASoti variants to enable reversible photoswitching of the red form. This result is achieved by rational and site-saturated mutagenesis of the M163 and F177 residues.

Lactobacilli and Klebsiella: Two Opposites in the Fight for Human Health.

The problem of antibiotic resistance is currently very acute. Numerous research and development of new antibacterial drugs are being carried out that could help cope with various infectious agents. One of the promising directions for the search for new antibacterial drugs is the search among the probiotic strains present in the human gastrointestinal tract.

Antibiotic Adjuvant 4-Hexylresorcinol Enhances the Efficiency of Antituberculosis Drugs.

We studied the possibility of using 4-hexylresorcinol to increase the efficiency of anti-mycobacterial chemotherapy. In an in vitro experiment, 4-hexylresorcinol increased the efficiency of rifampicin, kanamycin, and isoniazid against Mycobacterium smegmatis by 3-5 times. Experiments in sanitation of BALB/c mice infected with M.

In-Depth Genome Characterization and Pan-Genome Analysis of Strain KMM 296, a Producer of Highly Active Alkaline Phosphatase; Proposal for the Reclassification of and as the Later Heterotypic Synonyms of and , and Emended Description of the Species and .

A strictly aerobic, Gram-stain-negative, rod-shaped, and motile bacterium, designated strain KMM 296, isolated from the coelomic fluid of the mussel , was investigated in detail due to its ability to produce a highly active alkaline phosphatase CmAP of the structural family PhoA. A previous taxonomic study allocated the strain to the species , a member of the family of the class . However, 16S rRNA gene sequencing showed KMM 296's relatedness to NRIC 0815.

Nonsteady-State Electric Circuit in Electrophoresis on Paper: Thermal Consideration of Electrophoretic Lateral-Flow Assays.

Nonsteady-state behaviors are not expected in electric circuits that lack significant capacitance, inductivity, and/or active feedback. Here, we report that electrophoresis on paper─used, e.g.

Molecular mechanism of rhinovirus escape from the Pyrazolo[3,4-d]pyrimidine capsid-binding inhibitor OBR-5-340 via mutations distant from the binding pocket: Derivatives that brake resistance.

Rhinoviruses (RVs) cause the common cold. Attempts at discovering small molecule inhibitors have mainly concentrated on compounds supplanting the medium chain fatty acids residing in the sixty icosahedral symmetry-related hydrophobic pockets of the viral capsid of the Rhinovirus-A and -B species. High-affinity binding to these pockets stabilizes the capsid against structural changes necessary for the release of the ss(+) RNA genome into the cytosol of the host cell.

Photochemical activity in developing pea (Pisum sativum L.) cotyledons depends on the light transmittance of covering tissues and the spectral composition of light.

Many crops require not only leaf photosynthesis for their seed development but also the photochemical reactions that occur in the seeds. The purpose of this work was a comparative analysis of light transmittance and photochemical activity in the leaves of Pisum sativum L. and its pericarp, seed coat, and cotyledons at the early, middle, and late maturation stages.

Novel His-tag Variants for Insertion Inside Polypeptide Chain.

His-tags are protein affinity tags ubiquitously used due to their convenience and effectiveness. However, in some individual cases, the attachment of His-tags to a protein's N- or C-termini resulted in impairment of the protein's structure or function, which led to attempts to include His-tags inside of polypeptide chains. In this work, we describe newly designed internal His-tags, where two triplets of histidine residues are separated by glycine residues to avoid steric hindrances and consequently minimize their impact on the protein structure.

Antidepressant-like Effect of the Eburnamine-Type Molecule Vindeburnol in Rat and Mouse Models of Ultrasound-Induced Depression.

Vindeburnol (VIND, RU24722, BC19), a synthetic molecule derived from the eburnamine-vincamine alkaloid group, has many neuropsychopharmacological effects, but its antidepressant-like effects are poorly understood and have only been described in a few patents. To reliably estimate this effect, vindeburnol was studied in a model of long-term variable-frequency ultrasound (US) exposure at 20-45 kHz in male Wistar rats and BALB/c mice. Vindeburnol was administered chronically for 21 days against a background of simultaneous ultrasound exposure at a dose of 20 mg/kg intraperitoneally (IP).

The accumulation of methylated porphyrins in dormant cells of Mycolicibacterium smegmatis is accompanied by a decrease in membrane fluidity and an impede of the functioning of the respiratory chain.

Transition of Mycolicibacterium smegmatis (Msm) and Mycobacterium tuberculosis to dormancy in vitro is accompanied by an accumulation of free methylated forms of porphyrins (tetramethyl coproporphyrin - TMC) localized in the cell wall of dormant bacteria. A study of the fluorescence anisotropy of BODIPY based fluorescent probes on individual cell level using confocal microscope revealed significant changes in this parameter for BODIPY FL C16 from 0.05 to 0.

Structure-Functional Examination of Novel Ribonucleoside Hydrolase C (RihC) from LR1.

Ribonucleoside hydrolase C (RihC, EC 3.2.2.