A mediator microbial biosensor for assaying general toxicity.

A mediator biosensor based on Paracoccus yeei bacteria for assaying the toxicity of perfumery and cosmetics samples was developed. An approach to selecting an electron-transport mediator based on the heterogeneous electron transfer constants for investigated mediators (ks) and the mediator-biomaterial interaction constants (kinteract) was proposed. Screening of nine compounds as potential mediators showed a ferrocene mediator immobilized in graphite paste to have the highest efficiency of electron transfer to the graphite-paste electrode (the heterogeneous transfer constant, 0.4 ±â€¯0.1 cm/s) and a high constant of interaction with P. yeei (0.023 ±â€¯0.001 dm3/(g·s)). A biosensor for toxicity assessment based on the ferrocene mediator and P. yeei bacteria was formed. The biosensor was tested on samples of four heavy metals (Cu2+, Zn2+, Pb2+, Cd2+) and two phenols (phenol and p-nitrophenol). Proceeding from the EC50 index, it was found that the use of the ferrocene mediator made the biosensor more sensitive to investigated toxicants than most analogues described. Toxicity determination of four perfumery and cosmetics samples by the developed biosensor showed prospects of using this system for real-time toxicity monitoring of samples.

Inhibition of Neutrophil Elastase and Cathepsin G As a New Approach to the Treatment of Psoriasis: From Fundamental Biology to Development of New Target-Specific Drugs.

Psoriasis therapy remains an extremely relevant area of modern drug design, due to necessity of adverse reaction reduction, inherent for actual methods of therapy. It was established that two serine proteases-neutrophil elastase 1 (HNE1) and cathepsin G (CatG)-are the key agents in psoriasis development. The collected molecular data for the presented targets form the basis for the molecular modeling strategy for the search for and identification of new target-specific inhibitors. The result of this work is a group of high-priority small-molecule compounds with double-targeted affinity, which are able to suppress the pro-psoriatic processes induced by the considered serine proteases at the initial stage of the disease.

An Integrated Method of Instrumental Microbiotesting of Environmental Safety of Various Products, Wastes, and Territories.

The described microbiotesting technique provides the recording of pH changes, redox potential, electrical conductivity, optical density, light scattering and luminescence intensities, and other parameters of samples with viable test microorganisms incubated in a liquid nutrient medium in the presence and absence of the tested factors. The results of using this system for the analysis of pro- and antibiotic activity of various oil products, as well as weak electromagnetic fields of the megahertz range, are presented. It has been shown that the proposed technique, compared to the standard methods, yields more detailed and objective information and is less time- and labor-consuming.

Optimization of Heterologous Expression of Insulin Receptor-Related Receptor Ectodomain.

In this paper, we present an approach to optimize the heterologous expression of the receptor tyrosine kinase IRR, which further simplifies the purification of the IRR from the medium and increases the final yield. The approach proposed by us can find application in the biotechnological production of other large-scale recombinant proteins produced for medical purposes.

Biotechnological Method of Preparation and Characterization of Recombinant Antimicrobial Peptide Avicin A from Enterococcus avium.

Avicin A is a bacteriocin from the gram-positive bacterium Enterococcus avium. It exhibits a high microbicidal activity against bacteria of the genus Listeria, a causative agent of the severe human infection listeriosis. We developed a biotechnological method for obtaining avicin A and characterized its structure and biological activity. We also proposed a possible mechanism of the antimicrobial action of avicin A.

New Method of Integrated Photofluorescence Microbiotesting.

A biotesting procedure that makes it possible to record the changes in the intensities of elastic light scattering, light absorption, and intrinsic photofluorescence of the protein component, as well as the determination of the concentration and structuring coefficients of the genomic component, of the samples with viable unicellular test organisms incubated in a liquid nutrient medium in the presence and absence of various external chemical factors, is described. The results of the analysis of the antibiotic activity of various metal cations with the use of this technique are presented. This technique is much more rapid, objective, and comprehensive for the assessment of the effect on the reproduction rate, metabolic activity, and genome structure of the test organisms from the samples of various products, wastes, etc. than standard visual microbiotesting methods.

Fluorescent DNA Probes: Study of Properties and Methods of Application.

The results of long-term author's studies of the optical and complex-forming properties of more than 30 synthetic low-molecular-weight fluorophores specific for DNA are described. These studies made it possible to significantly expand the already existing database of properties of such compounds, clarify the ideas about the patterns linking the mentioned properties of fluorophores with their structure, and formulate recommendations on designing new effective DNA-specific fluorophores. The results of these studies can be used, in particular, in the development of new rapid methods for diagnosing various diseases, biotesting of probiotic and antibiotic properties of various products and wastes, etc.

Development of target delivery system based on actinomycin class drugs and recombinant alpha-fetoprotein.

A recombinant alpha-fetoprotein (rAFP) was obtained in the yeast P. pastoris system, and its functional activity was confirmed. A method for producing polymer particles loaded with dactinomycin was developed, and a conjugate of these nanoparticles with rAFP was synthesized. The efficiency of the obtained conjugate on the HeLa, SKOV3, and MG-63 tumor cells and the absence of toxicity on the normal cells was shown. Experiments in vivo demonstrated a significant increase in the antitumor efficacy of the conjugate at a lower general toxicity as compared to the commercially available dactinomycin.

[Liposomal form of lipoic acid: preparation and determination of antiplatelet and antioxidant activity]. / Liposomal'naia forma lipoevoi kisloty: poluchenie i opredelenie antiagregatsionnoi i antioksidantnoi aktivnosti.

Optimal conditions for obtaining phosphatidylholine (PC) liposomes with lipoic acid (LA) are chosen that lead to the formation of nanoparticles with a size of 175¸284 nm with efficiency (extent) of inclusion of LA in liposomes equal 85% and characterized by a slow release of substance from the nanoparticles. The effect of "empty" liposomes and liposomal form of LA on platelet aggregation induced by arachidonic acid (AA) is established. It is found that liposomes with LА inhibit platelet aggregation, caused by AА, to 80%. In addition, it is shown that "empty" liposomes slightly (to 30%) suppress platelet aggregation, caused by AА. The amount of TBA-sensitive products in samples of platelet-rich plasma (PRP) incubated with liposomal LA is determined. It is shown that LA in the composition of liposomes retains its antioxidant properties, and the amount of products of lipid peroxidation in platelet-rich plasma decreases in a dose-dependent manner when arachidonic acid is used as an inductor of platelet aggregation. It is assumed that the antiplatelet action of the liposomal form of LА is induced by inhibition of the initiation of lipid peroxidation products caused by exogenous inducer AА. It is supposed that, after additional research, the liposomal form of LA can be considered as a new drug in complex treatment of cerebral ischemia.

Design of a stable cell line producing a recombinant monoclonal anti-TNFα antibody based on a CHO cell line.

Recombinant monoclonal antibodies (mAbs) against tumor necrosis factor alpha are widely used in the biopharmaceutical therapy of autoimmune diseases. Currently, a large number of drugs based on these antibodies are available. Accordingly, the development of these products for the Russian market is an important goal. The aim of the current study is to describe the development of one such technology. CHO-DG44-derived cell lines producing mAb were developed using two strategies, one based on individual clones and the other based on cell pools. To obtain recombinant cell lines with highly amplified genes of interest, the clones underwent dihydrofolate reductase-mediated gene amplification. Using the best strategy for the selection and amplification of mAb-producing clones, we achieved the production of more than 1 g/L in small scale, non-optimized conditions.