Publications by authors named "Maria S Zharkova"

Article Synopsis
  • - Innate immunity in invertebrates provides effective antimicrobial peptides (AMPs) that combat drug-resistant infections, sparking interest in finding new β-hairpin AMPs from worm proteins with a BRICHOS domain.
  • - Researchers discovered new BRICHOS AMPs from caecilians, a lesser-known group of vertebrates, revealing similarities to lung surfactants and suggesting a unique lung function.
  • - The identified peptides show strong antibacterial properties against multidrug-resistant ESKAPE pathogens while being low in toxicity, indicating potential as a new antibiotic model and highlighting a previously unrecognized lung immunity mechanism.
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The link between copper metabolism and tumor progression motivated us to use copper chelators for suppression of tumor growth. We assume that silver nanoparticles (AgNPs) can be used for lowering bioavailable copper. Our assumption is based on the ability of Ag(I) ions released by AgNPs in biological media and interfere with Cu(I) transport.

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Article Synopsis
  • * The interaction between AMPs and antiseptics is less studied than AMPs and antibiotics, yet analyzing their combined antibacterial and cytotoxic activities reveals both synergistic and antagonistic effects.
  • * Optimizing AMP/antiseptic combinations could enhance treatment efficacy, reduce toxicity, and limit bacterial resistance, but careful evaluation is needed to avoid potential interference that may diminish AMP effectiveness.
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Silver nanoparticles (AgNPs) and antimicrobial peptides or proteins (AMPs/APs) are both considered as promising platforms for the development of novel therapeutic agents effective against the growing number of drug-resistant pathogens. The observed synergy of their antibacterial activity suggested the prospect of introducing antimicrobial peptides or small antimicrobial proteins into the gelatinized coating of AgNPs. Conjugates with protegrin-1, indolicidin, protamine, histones, and lysozyme were comparatively tested for their antibacterial properties and compared with unconjugated nanoparticles and antimicrobial polypeptides alone.

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Article Synopsis
  • - Proline-rich antimicrobial peptides (PR-AMPs) like ChBac3.4, isolated from goat leukocytes, show strong effectiveness against Gram-negative bacteria with low toxicity to human cells, making them promising for antibiotic development.
  • - A study on ChBac3.4 explored its unique properties, antibacterial effectiveness against drug-resistant strains, and potential as a lead for both antimicrobial and anticancer therapies, while assessing how structural changes influenced toxicity and activity.
  • - Findings revealed that modifications such as terminal amidation and increased hydrophobicity altered the peptides' effectiveness and side effects, highlighting a balance between antibacterial potency and selectivity towards tumor cells, while some variants exhibited unexpected toxicity toward human red blood cells.
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Antimicrobial peptides (AMPs) were firstly discovered as cytotoxic substances that killed bacteria. Later they were described as biologically active peptides that are able not only to kill invaders but also to modulate host immunity. In particular, it is shown that human antimicrobial peptides are able to influence the activity of different innate and adaptive immunity components, thus, obviously, they also participate in autoimmune processes.

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Arenicin-1, a β-sheet antimicrobial peptide isolated from the marine polychaeta coelomocytes, has a potent, broad-spectrum microbicidal activity and also shows significant toxicity towards mammalian cells. Several variants were rationally designed to elucidate the role of structural features such as cyclization, a certain symmetry of the residue arrangement, or the presence of specific residues in the sequence, in its membranolytic activity and the consequent effect on microbicidal efficacy and toxicity. The effect of variations on the structure was probed using molecular dynamics simulations, which indicated a significant stability of the β-hairpin scaffold and showed that modifying residue symmetry and β-strand arrangement affected both the twist and the kink present in the native structure.

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Rapidly growing resistance of pathogenic bacteria to conventional antibiotics leads to inefficiency of traditional approaches of countering infections and determines the urgent need for a search of fundamentally new anti-infective drugs. Antimicrobial peptides (AMPs) of the innate immune system are promising candidates for a role of such novel antibiotics. However, some cytotoxicity of AMPs toward host cells limits their active implementation in medicine and forces attempts to design numerous structural analogs of the peptides with optimized properties.

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Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder. Amyloid-β (Aβ) aggregation is likely to be the major cause of AD. In contrast to humans and other mammals, that share the same Aβ sequence, rats and mice are invulnerable to AD-like neurodegenerative pathologies, and Aβ of these rodents (ratAβ) has three amino acid substitutions in the metal-binding domain 1-16 (MBD).

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New oxazolinyl derivatives of [17(20)E]-pregna-5,17(20)-diene: 2'-{[(E)-3β-hydroxyandrost-5-en-17-ylidene]methyl}-4',5'-dihydro-1',3'-oxazole 1 and 2'-{[(E)-3β-hydroxyandrost-5-en-17-ylidene]methyl}-4',4'-dimethyl-4',5'-dihydro-1',3'-oxazole 2 were evaluated as potential CYP17A1 inhibitors in comparison with 17-(pyridin-3-yl)androsta-5,16-dien-3β-ol 3 (abiraterone). Differential absorption spectra of human recombinant CYP17A1 in the presence of compound 1 (λmax=422 nm, λmin=386 nm) and compound 2 (λmax=416 nm) indicated significant differences in enzyme/inhibitors complexes. CYP17A1 activity was measured using electrochemical methods.

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Cytochromes P450 comprise a large superfamily and several of their isoforms play a crucial role in metabolism of xenobiotics, including drugs. Although these enzymes demonstrate broad and cross-substrate specificity, different cytochrome P450 subfamilies exhibit certain selectivity for some types of substrates. Analysis of amino acid residues of the active sites of six cytochrome subfamilies (CYP1А, CYP2А, CYP2С, CYP2D, CYP2E and CYP3А) enables to define subfamily-specific patterns that consist of four residues.

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