Role of Humic Substances in the (Bio)Degradation of Synthetic Polymers under Environmental Conditions.

Information on the detection of the presence and potential for degradation of synthetic polymers (SPs) under various environmental conditions is of increasing interest and concern to a wide range of specialists. At this stage, there is a need to understand the relationship between the main participants in the processes of (bio)degradation of SPs in various ecosystems (reservoirs with fresh and sea water, soils, etc.), namely the polymers themselves, the cells of microorganisms (MOs) participating in their degradation, and humic substances (HSs).

Action enhancement of antimicrobial peptides by their combination with enzymes hydrolyzing fungal quorum molecules.

Recently, the lactonase activity of several enzymes (lactonase AiiA, organophosphate hydrolase (His-OPH) and New Delhi metallo-β-lactamase (NDM-1)) was revealed in the hydrolysis of lactone-containing fungal Quorum Sensing molecules (FQSM). This study was aimed at the investigation of possible use of these enzymes as components of antifungal combinations with antimicrobial peptides (AMPs) to increase their action efficiency against various fungi. For this, the interaction of various AMPs with AiiA, NDM-1 or His-OPH, as well as the effect of AMPs on the catalytic characteristics of these enzymes in the hydrolysis of FQSM in enzyme/AMP combinations, were studied using in silico computer modeling methods.

"Stop, Little Pot" as the Motto of Suppressive Management of Various Microbial Consortia.

The unresolved challenges in the development of highly efficient, stable and controlled synthetic microbial consortia, as well as the use of natural consortia, are very attractive for science and technology. However, the consortia management should be done with the knowledge of how not only to accelerate but also stop the action of such "little pots". Moreover, there are a lot of microbial consortia, the activity of which should be suppressively controlled.

Using Fungi in Artificial Microbial Consortia to Solve Bioremediation Problems.

There is currently growing interest in the creation of artificial microbial consortia, especially in the field of developing and applying various bioremediation processes. Heavy metals, dyes, synthetic polymers (microplastics), pesticides, polycyclic aromatic hydrocarbons and pharmaceutical agents are among the pollutants that have been mainly targeted by bioremediation based on various consortia containing fungi (mycelial types and yeasts). Such consortia can be designed both for the treatment of soil and water.

Enzymes with Lactonase Activity against Fungal Quorum Molecules as Effective Antifungals.

Since the growing number of fungi resistant to the fungicides used is becoming a serious threat to human health, animals, and crops, there is a need to find other effective approaches in the eco-friendly suppression of fungal growth. One of the main mechanisms of the development of resistance in fungi, as well as in bacteria, to antimicrobial agents is quorum sensing (QS), in which various lactone-containing compounds participate as signaling molecules. This work aimed to study the effectiveness of action of enzymes exhibiting lactonase activity against fungal signaling molecules.

Luminescent Bacteria as Bioindicators in Screening and Selection of Enzymes Detoxifying Various Mycotoxins.

Interest in enzymes capable of neutralizing various mycotoxins is quite high. The methods used for the screening and selection of enzymes that catalyze the detoxification of mycotoxins should be sensitive and fast. However toxic compounds can be generated under the action of such enzymes.

Artificial Humic Substances as Biomimetics of Natural Analogues: Production, Characteristics and Preferences Regarding Their Use.

Various processes designed for the humification (HF) of animal husbandry wastes, primarily bird droppings, reduce their volumes, solve environmental problems, and make it possible to obtain products with artificially formed humic substances (HSs) as analogues of natural HSs, usually extracted from fossil sources (coal and peat). This review studies the main characteristics of various biological and physicochemical methods of the HF of animal wastes (composting, anaerobic digestion, pyrolysis, hydrothermal carbonation, acid or alkaline hydrolysis, and subcritical water extraction). A comparative analysis of the HF rates and HS yields in these processes, the characteristics of the resulting artificial HSs (humification index, polymerization index, degree of aromaticity, etc.

Various Biomimetics, Including Peptides as Antifungals.

Biomimetics, which are similar to natural compounds that play an important role in the metabolism, manifestation of functional activity and reproduction of various fungi, have a pronounced attraction in the current search for new effective antifungals. Actual trends in the development of this area of research indicate that unnatural amino acids can be used as such biomimetics, including those containing halogen atoms; compounds similar to nitrogenous bases embedded in the nucleic acids synthesized by fungi; peptides imitating fungal analogs; molecules similar to natural substrates of numerous fungal enzymes and quorum-sensing signaling molecules of fungi and yeast, etc. Most parts of this review are devoted to the analysis of semi-synthetic and synthetic antifungal peptides and their targets of action.

Metal Nanomaterials and Hydrolytic Enzyme-Based Formulations for Improved Antifungal Activity.

Active research of metal-containing compounds and enzymes as effective antifungal agents is currently being conducted due to the growing antifungal resistance problem. Metals are attracting special attention due to the wide variety of ligands that can be used for them, including chemically synthesized and naturally obtained variants as a result of the so-called "green synthesis". The main mechanism of the antifungal action of metals is the triggering of the generation and accumulation of reactive oxygen species (ROS).

Quorum Sensing as a Trigger That Improves Characteristics of Microbial Biocatalysts.

Quorum sensing (QS) of various microorganisms (bacteria, fungi, microalgae) today attracts the attention of researchers mainly from the point of view of clarifying the biochemical basics of this general biological phenomenon, establishing chemical compounds that regulate it, and studying the mechanisms of its realization. Such information is primarily aimed at its use in solving environmental problems and the development of effective antimicrobial agents. This review is oriented on other aspects of the application of such knowledge; in particular, it discusses the role of QS in the elaboration of various prospective biocatalytic systems for different biotechnological processes carried out under aerobic and anaerobic conditions (synthesis of enzymes, polysaccharides, organic acids, etc.

Progressive Biocatalysts for the Treatment of Aqueous Systems Containing Pharmaceutical Pollutants.

The review focuses on the appearance of various pharmaceutical pollutants in various water sources, which dictates the need to use various methods for effective purification and biodegradation of the compounds. The use of various biological catalysts (enzymes and cells) is discussed as one of the progressive approaches to solving problems in this area. Antibiotics, hormones, pharmaceuticals containing halogen, nonsteroidal anti-inflammatory drugs, analgesics and antiepileptic drugs are among the substrates for the biocatalysts in water purification processes that can be carried out.

Destruction of Mycotoxins in Poultry Waste under Anaerobic Conditions within Methanogenesis Catalyzed by Artificial Microbial Consortia.

To reduce the toxicity of modern feeds polluted by mycotoxins, various sorbents are added to them when feeding animals. A part of the mycotoxins is excreted from the body of animals with these sorbents and remains in the manure. As a result, bulk animal wastes containing mixtures of mycotoxins are formed.

Advanced Situation with Recombinant Toxins: Diversity, Production and Application Purposes.

Today, the production and use of various samples of recombinant protein/polypeptide toxins is known and is actively developing. This review presents state-of-the-art in research and development of such toxins and their mechanisms of action and useful properties that have allowed them to be implemented into practice to treat various medical conditions (including oncology and chronic inflammation applications) and diseases, as well as to identify novel compounds and to detoxify them by diverse approaches (including enzyme antidotes). Special attention is given to the problems and possibilities of the toxicity control of the obtained recombinant proteins.

Synergistic Antimicrobial Action of Lactoferrin-Derived Peptides and Quorum Quenching Enzymes.

Combined use of various antimicrobial peptides (AMPs) with enzymes that hydrolyze the signaling molecules of the resistance mechanism of various microorganisms, quorum sensing (QS), to obtain effective antimicrobials is one of the leading approaches in solving the antimicrobial resistance problem. Our study investigates the lactoferrin-derived AMPs, lactoferricin (Lfcin), lactoferampin and Lf(1-11), as potential partners for combination with enzymes hydrolyzing lactone-containing QS molecules, the hexahistidine-containing organophosphorus hydrolase (His-OPH) and penicillin acylase, to obtain effective antimicrobial agents with a scope of practical application. The possibility of the effective combination of selected AMPs and enzymes was first investigated in silico using molecular docking method.

Combination of Enzymes with Materials to Give Them Antimicrobial Features: Modern Trends and Perspectives.

Multidrug-resistant bacteria form serious problems in many areas, including medicine and the food industry. At the same time, great interest is shown in the transfer or enhancement of antimicrobial properties to various materials by modifying them with enzymes. The use of enzymes in biomaterials with antimicrobial properties is important because enzymes can be used as the main active components providing antimicrobial properties of functionalized composite biomaterials, or can serve as enhancers of the antimicrobial action of certain substances (antibiotics, antimicrobial peptides, metal nanoparticles, etc.

Carrier Variety Used in Immobilization of His-OPH Extends Its Application Areas.

Organophosphorus hydrolase, containing a genetically introduced hexahistidine sequence (His-OPH), attracts the attention of researchers by its promiscuous activity in hydrolytic reactions with various substrates, such as organophosphorus pesticides and chemical warfare agents, mycotoxins, and -acyl homoserine lactones. The application of various carrier materials (metal-organic frameworks, polypeptides, bacterial cellulose, polyhydroxybutyrate, succinylated gelatin, etc.) for the immobilization and stabilization of His-OPH by various methods, enables creation of biocatalysts with various properties and potential uses, in particular, as antidotes, recognition elements of biosensors, in fibers with chemical and biological protection, dressings with antimicrobial properties, highly porous sorbents for the degradation of toxicants, including in flow systems, etc.

Self-Assembling Enzymatic Nanocomplexes with Polypeptides and Low-Weight Organic Compounds: Preparation, Characterization, and Application of New Antibacterials.

The self-assembling of nanosized materials is a promising field for research and development. Multiple approaches are applied to obtain inorganic, organic and composite nanomaterials with different functionality. In the present work, self-assembling nanocomplexes (NCs) were prepared on the basis of enzymes and polypeptides followed by the investigation of the influence of low-molecular weight biologically active compounds on the properties of the NCs.

Strategies for variable regulation of methanogenesis efficiency and velocity.

Combinations of various strategic approaches to the suppression of methanogenesis and the formation of biogas with a simultaneous decrease in the ratio of methane in its composition were investigated. Introduction of methanogenesis suppressors such as redox derivatives of humic acids, potassium persulfate (KSO), possessing oxidizing and electron acceptor properties, enzyme hexahistidine-containing organophosphorus hydrolase with high lactonase activity and polypeptide antimicrobial agent bacitracin into the media with anaerobic consortia were studied. The effect of these substances was directed at various participants of the natural methanogenic consortium, as well as on the biochemical processes carried out by them.

"Universal" Antimicrobial Combination of Bacitracin and His-OPH with Lactonase Activity, Acting against Various Bacterial and Yeast Cells.

The effect of Bacitracin as an antibiotic acting against Gram-positive bacterial cells was evaluated in combination with hexahistidine-containing organophosphate hydrolase (His-OPH), possessing lactonase activity against various -acylhomoserine lactones produced by most Gram-negative bacteria as quorum-sensing molecules. The molecular docking technique was used to obtain in silico confirmation of possible interactions between molecules of His-OPH and Bacitracin as well as the absence of a significant influence of such interactions on the enzymatic catalysis. The in vitro experiments showed a sufficient catalytic efficiency of action of the His-OPH/Bacitracin combination as compared to the native enzyme.

Sulfur containing mixed wastes in anaerobic processing by new immobilized synthetic consortia.

Methanogenic biotransformation of unusual substrates (sulfur (S)-containing wastes: non-purified vacuum gas oil, straight-run gasoline fraction (Naphtha), gas condensate, and straight-run diesel fraction) coming from oil industry after their oxidative desulfurization was investigated. Nitrogen-containing wastes (hydrolysates of chicken manure and Chlorella vulgaris biomass) were added as co-substrates to mixture with oil industry wastes. The 100 % conversion of S-organic compounds to inorganic sulfide accumulated in the reaction liquid medium was achieved with simultaneous production of biogas containing high methane percent (greater than 70 %).

Degradation of mycotoxins in mixtures by combined proteinous nanobiocatalysts: In silico, in vitro and in vivo.

New combined proteinous (enzymatic) nanobiocatalysts capable of destructing mycotoxins in mixtures were developed and investigated in vitro and in vivo. Candidate enzymes for such combined biocatalysts were computationally screened using molecular docking of mycotoxins to the proteins. Catalytic characteristics of the 7 selected enzymes were estimated in the potential reactions with various mycotoxins (aflatoxin B, citrinin, deoxynivalenol, ergotamine, fumonisin B, gliotoxin, ochratoxin A, patulin, sterigmatocystin, T-2 toxin, zearalenone) at different pH values.

"Unity and Struggle of Opposites" as a Basis for the Functioning of Synthetic Bacterial Immobilized Consortium That Continuously Degrades Organophosphorus Pesticides.

This work was aimed at the development of an immobilized artificial consortium (IMAC) based on microorganisms belonging to the Gram-positive and Gram-negative bacterial cells capable of jointly carrying out the rapid and effective degradation of different organophosphorus pesticides (OPPs): paraoxon, parathion, methyl parathion, diazinon, chlorpyrifos, malathion, dimethoate, and demeton-S-methyl. A cryogel of poly(vinyl alcohol) was applied as a carrier for the IMAC. After a selection was made between several candidates of the genera and , the required combination of two cultures ( and ) was found.

Combined Modification of Fiber Materials by Enzymes and Metal Nanoparticles for Chemical and Biological Protection.

To obtain fiber materials with pronounced chemical-biological protection, metal (Zn or Ta) nanoparticles were jointly applied with polyelectrolyte complexes of enzymes and polypeptides being their stabilizers. Computer modeling revealed the preferences between certain polyelectrolyte partners for -acyl-homoserine lactone acylase and hexahistidine-tagged organophosphorus hydrolase (His-OPH) possessing the quorum quenching (QQ) behavior with bacterial cells. The combinations of metal nanoparticles and enzymes appeared to function better as compared to the combinations of the same QQ-enzymes with antibiotics (polymyxins), making it possible to decrease the applied quantities by orders of magnitude while giving the same effect.

Decarboxylases as hypothetical targets for actions of organophosphates: Molecular modeling for prediction of hidden and unexpected health threats.

The rise of various neurodegenerative disorders are somewhat correlating with the worldwide application of multiple anthropogenic toxicants. Though different possible targets were revealed to date, for example, for organophosphorus compounds (OPs), plenty of questions remain. Several decarboxylases (aromatic amino acid decarboxylase, AADC; histidine decarboxylase, HDC; glutamate decarboxylase, GAD) catalyze the biosynthesis of neurotransmitters and neuromodulators and contain pyridoxal phosphate (PLP) as a cofactor.

Model Fuel Oxidation in the Presence of Molybdenum-Containing Catalysts Based on SBA-15 with Hydrophobic Properties.

We have studied for the first time the role of hydrophobicity of the mesoporous silicate SBA-15 on the activity and the service life of a catalyst in the peroxide oxidation of sulfur-containing compounds. Immobilization of the molybdate anion on the SBA-15 support via ionic bonding with triethylammonium groups allows us not only to decrease the reaction temperature to a relatively low value of 60 °C without a drop in the dibenzothiophene conversion degree but also to increase the service life of the catalyst to many times that of the known analogs. The support and catalyst structures were investigated by low-temperature nitrogen adsorption/desorption, Fourier-transform infrared spectroscopy, X-ray fluorescence analysis, and transmission electron microscopy.