Moscow University Chemistry Bulletin

Melnikov, M. Ya.; Gromov, O. I.; Pergushov, V. I.; Pomogailo, D. A.; Sorokin, I. D.

2024 Moscow University Chemistry Bulletin

doi: 10.3103/s0027131424700111

The review is dedicated to the photochemical reactions of radical cations (RC) of various organic oxygen-containing compounds stabilized in low-temperature matrices. The nature of RC and the products of their photochemical reactions has been established via quantum chemistry, electron paramagnetic resonance (EPR) and low-temperature optical spectroscopy. Depending on the structure of the precursor molecule, various mechanisms of photoconversion arise for these RC: charge transfer to matrix molecules, hydrogen atom and proton transfer, isomerization, dissociation. This study allowed us to posit that there is no correlation between the structure of the molecule of the precursor molecule and the variety of available phototransformation channels for the corresponding RC in frozen matrices.

Shishova, V. V.; Lokteva, E. S.; Maksimov, G. S.; Maslakov, K. I.; Kaplin, I. Yu.; Maksimov, S. V.; Golubina, E. V.

2024 Moscow University Chemistry Bulletin

doi: 10.3103/s0027131424700123

Pd/ZrO2 and Pd/ZrO2SiO2 catalysts prepared by wet impregnation and reduced with H2 under mild (30°C, aqueous suspension) or harsh (320°C) conditions are compared in the hydrodechlorination of the microecotoxicant diclofenac (DCF) in an aqueous solution at 30°С. According to the TPR and XPS data, the addition of SiO2 to the support reduces the degree of metal-support interaction and facilitates the reduction of palladium. Despite the lower Pd0 fraction, the Pd/ZrO2 catalyst is more active in the batch reactor: after reduction at 320°С, it slightly, and after mild reduction, significantly (7 times), exceeds Pd/ZrO2SiO2 in catalytic activity. XRD and TEM show a wider size distribution of palladium nanoparticles in the Pd/ZrO2 sample, while low-temperature N2 adsorption, XPS, and TPR demonstrated better accessibility of palladium on the Pd/ZrO2 surface due to the reduced decoration by the support components and increased pore size. These features explain the increased activity of Pd/ZrO2. Testing in the flow system demonstrated higher DCF conversion in the presence of catalysts reduced at 320°C and higher stability of Pd/ZrO2SiO2 compared to Pd/ZrO2. The stability is ensured by the increased reducibility of Pd2+ with H2 and by the developed surface of Pd/ZrO2SiO2, which prevents deactivation under the action of HCl released in hydrodechlorination.

Grigoryan, I. V.; Spiridonov, V. V.; Adelyanov, A. M.; Koksharov, Yu. A.; Potapenkov, K. V.; Taranov, I. V.; Khomutov, G. B.; Yaroslavov, A. A.

2024 Moscow University Chemistry Bulletin

doi: 10.3103/s0027131424700135

This paper presents new colloidal systems that have prospects for use as carriers of medicinal compounds and are polymer complexes based on polyacrylic acid molecules of various molecular weights and biogenic polyamine, additionally modified with magnetic iron oxide nanoparticles. The main physicochemical characteristics of the resulting polycomplexes are determined. The possibility of incorporating a doxorubicin medicinal compound in the polycomplexes is demonstrated, and the magnetic properties of the polycomplexes functionalized with magnetic iron oxide nanoparticles are studied.

Makeeva, A. A.; Shumilkin, A. S.; Ryzhkova, A. S.; Vernaya, O. I.; Shabatin, A. V.; Semenov, A. M.; Shabatina, T. I.

2024 Moscow University Chemistry Bulletin

doi: 10.3103/s0027131424700147

Biopolymer materials based on natural collagen (gelatin, hydrolyzed collagen) are widely used in the food, pharmaceutical, and cosmetic industries due to their low toxicity, high biocompatibility, low antigenicity, and unique mechanical and technological properties. Hydrolyzed collagen, unlike gelatin, is formed by peptides with a lower molecular weight. Its advantages are higher bioavailability and biodegradability in comparison with gelatin. In this study, biopolymer matrices containing a dioxidine antibacterial drug are obtained based on hydrolyzed collagen using low-temperature technologies. It is shown that, varying synthesis parameters such as the concentration of hydrolyzed collagen in the precursor solution (from 1 to 10%), matrix crosslinking time (0.1–24 h), and cryoforming temperature (–30 and –196°C), it is possible to change the morphology and structure of the matrix, its degradation time, and drug release time. The composition and structure of dioxidine/hydrolyzed collagen systems are characterized by SEM and IR and UV spectroscopy. The antibacterial activity of the resulting dioxidine/hydrolyzed collagen systems against E. coli and S. aureus is characterized by the disk diffusion method.

Bogush, T. A.; Basharina, A. A.; Romanov, I. P.; Grishanina, A. N.; Bogush, E. A.; Scherbakov, A. M.; Ravcheeva, A. B.; Lee, A.; Kosorukov, V. S.

2024 Moscow University Chemistry Bulletin

doi: 10.3103/s0027131424700159

A quantitative assessment of the expression of estrogen receptors alpha (ERα) is carried out in 115 samples of non-small cell lung cancer (NSCLC) by an immunofluorescent assay and flow cytometry. It is shown that a high level of ERα of ≥20% predicts a higher aggressiveness of NSCLC than at a low level of <20%: median survival based on a follow-up period of 78 months increases by 1.5 times; the risk of death is reduced by a factor of almost 2.0 (p = 0.04). The time to death increases on average by 18 months in about 20% of patients with a low ERα expression. The results validate the informative value of the immunofluorescence analysis and flow cytometry for quantifying the ERα expression and substantiate the prospects of antiestrogen therapy as a new option for NSCLC treatment, in particular, by analogy with breast cancer—in a long-term adjuvant therapy in ERα+ NSCLC patients.

Gotmanova, N. N.; Bacheva, A. V.

2024 Moscow University Chemistry Bulletin

doi: 10.3103/s0027131424700160

This review is devoted to the consideration of pathological intracellular mechanisms characteristic of Huntington’s disease and the central role of huntingtin protein in these processes. The features of mutant huntingtin aggregates utilization by the ubiquitin–proteasome system and autophagy, as well as the possibilities of polyglutamine-containing substrates hydrolysis by proteasome are discussed.

Rastriga, N. V.; Eremeev, N. L.; Klimov, D. A.; Levashov, P. A.

2024 Moscow University Chemistry Bulletin

doi: 10.3103/s0027131424700172

In this study, an attempt is made to analyze the published data regarding the effectors of bacterial lysis in the presence of various bacteriolytic enzymes. Despite the differences between such enzymes, it is possible to identify certain general patterns of their action on a highly complex substrate—a living bacterial cell protected by a cell wall and additional complexes of biopolymers associated with it. Chicken and human lysozymes are the best known of these enzymes. They have some structural differences but are generally very similar in properties. Understanding the characteristics of the antibacterial action of bacteriolytic enzymes present both in medications and in the human immune system is extremely important for the development of new approaches to combat bacterial infections, including antibiotic-resistant ones. Moreover, certain logical and methodological approaches used to study bacteriolytic enzymes can be extremely useful for studying and describing other enzymes that affect complex polymer substrates in real biological situations.

Frank, L. A.; Krasitskaya, V. V.

2024 Moscow University Chemistry Bulletin

doi: 10.3103/s0027131424700184

This review presents the data on the structure of bioluminescent systems of marine animals that use coelenterazine-dependent luciferases as light-emitting proteins. It is shown that these luciferases and their genetic variants with new useful properties are successfully used as reporter molecules in a variety of analytical systems in vitro and in vivo due to the availability, stability, and high quantum yield of the reactions. Their application ensures a high level of sensitivity, simple design, and fast analysis.

Marynich, N. K.; Savitsky, A. P.

2024 Moscow University Chemistry Bulletin

doi: 10.3103/s0027131424700196

A search for amino acid residues, whose replacement could contribute to the optimal maturation of the moxSAASoti fluorescent protein at 37°C, is carried out. For many other fluorescent proteins, this characteristic was improved by chance through many rounds of random mutagenesis; however, we managed to find two positions, 74 and 125, which clearly affect the process of moxSAASoti maturation, which is verified by introducing substitutions at these positions by site-directed and site-saturation mutagenesis.

Ovsyannikov, V. O.; Mikhailova, A. Yu.; Budanova, U. A.; Sebyakin, Yu. L.

2024 Moscow University Chemistry Bulletin

doi: 10.3103/s0027131424700202

Recently, due to the growth in bacterial infections resistant to antibiotics, there is an urgent need for developing alternative antibacterial drugs. Alkyl-indolyl-L-lysines are a promising class of compounds; their amphiphilic structure is crucial in antimicrobial efficacy. A scheme is developed and five new derivatives of indolylbutyric and indolylacetic acids containing a polar amino acid residue with an ethylenediamine linker binding alkyl fragments with different lengths are synthesized. The antibacterial activity of the new amphiphiles against gram-positive and gram-negative bacterial strains is evaluated. The minimum binding energy of the synthesized compounds with human serum albumin (HSA) is determined by molecular docking. A lower affinity of the studied objects in comparison with control indolmycin is shown.