The use of bacteria of the genus Pseudomonas—destructors of persistent pollutants for biotechnologies of environmental purification—is an interesting area of research. The aim of this work was to study the potential of Pseudomonas mosselii strain 5(3) isolated from pesticide-contaminated soil as a degrader of C₇-C₁₀ perfluorocarboxylic acids (PFCAs) and analyze its complete genome. The genome of the strain has been fully sequenced. It consists of a chromosome with a length of 5,676,241 b.p. and containing a total of 5134 genes, in particular, haloalkane dehalogenase gene (dhaA), haloacetate dehalogenase H-1 gene (dehH1), fluoride ion transporter gene (crcB) and alkanesulfonate monooxygenase gene (ssuE), responsible for the degradation of fluorinated compounds. The strain P. mosselii 5(3) for was cultivated for 7 days in a liquid medium with various C₇-C₁₀ PFCAs as the sole source of carbon and energy, and completely disposed of them. The results of LC-MS analysis showed that the transformation takes place due to perfluorohexanoic acid with the release of various levels of stoichiometry (depending on PFCA) of fluorine ion mineralization indicators determined by ion chromatography. Thus, Pseudomonas mosselii strain 5(3) demonstrates a genetically confirmed high potential for the decomposition of C₇-C₁₀ PFCA.

Bacteria of the genus Pseudomonas are the most studied microorganisms that biodegrade persistent perfluoroorganic pollutants, and the research of their application for the remediation of environmental sites using biotechnological approaches remains relevant. The aim of this study was to investigate the ability of a known destructor of perfluorooctane sulfonic acid from the genus Pseudomonas to accelerate and enhance the destruction of long-chain perfluorocarboxylic acids (PFCAs), specifically perfluorooctanoic acid and perfluorononanoic acid, in water and soil in association with the strain P. mosselii 5(3), which has previously confirmed genetic potential for the degrading of PFCAs. The complete genome (5.86 million base pairs) of the strain 2,4-D, probably belonging to a new species of Pseudomonas, was sequenced, assembled, and analyzed. The genomes of both strains contain genes involved in the defluorination of fluorinated compounds, including haloacetate dehalogenase H-1 (dehH1) and haloalkane dehalogenase (dhaA). The strain 2,4-D also has a multicomponent enzyme system consisting of a dioxygenase component, an electron carrier, and 2-halobenzoate 1,2-dioxygenase (CbdA) with a preference for fluorides. The strain 2,4-D was able to defluorinate PFCAs in an aqueous cultivation system within 7 days, using them as the sole source of carbon and energy and converting them to perfluorheptanoic acid. It assisted strain 5(3) to convert PFCAs to perfluoropentanoic acid, accelerating the process by 24 h. In a model experiment for the bioaugmentation of microorganisms in artificially contaminated soil, the degradation of PFCAs by the association of pseudomonads also occurred faster and deeper than by the individual strains, achieving a degree of biodestruction of 75% over 60 days, with the perfluoropentanoic acid as the main metabolite. These results are of great importance for the development of methods for the biological recultivation of fluorinated organic pollutants for environmental protection and for understanding the fundamental mechanisms of bacterial interactions with these compounds.

Bacteria of the genus Pseudomonas are the most studied microorganisms in the biodestruction of persistent perfluoroorganic pollutants, and the research on their application for the remediation of environmental sites using biotechnological methods remains relevant. The aim of this study was to investigate the ability of a known destructor of perfluorooctane sulfonic acid from the genus Pseudomonas to accelerate and enhance the depth of destruction of long-chain perfluorocarboxylic acids (PFCAs), specifically perfluorooctanoic acid and perfluorononanoic acid, in water and soil in association with the strain P. mosselii 5(3), which has previously confirmed genetic potential for degrading PFCAs. The complete genome (length 5.86 million base pairs) of the strain 2,4-D, a new species of Pseudomonas, was sequenced, assembled, and analyzed. The genomes of both strains contain genes involved in the defluorination of fluorinated compounds, including haloacetate dehalogenase H-1 (dehH1) and haloalkane dehalogenase (dhaA). The strain 2,4-D also has a multi-component enzyme system consisting of a dioxygenase component, an electron carrier, and 2-halobenzoate 1,2-dioxygenase (CbdA) with a preference for fluorides. The strain 2,4-D was able to completely decarboxylate and defluorinate PFCAs in an aqueous cultivation system within 7 days, using them as the sole source of carbon and energy, but it only converted them to perfluorheptanoic acid. However, it assisted strain 5(3) (which defluorinated them during the same period to perfluorohexanoic acid) in converting PFCAs to perfluoropentanoic acid, accelerating the process by 24 hours. The degradation and transformation of the anionic acids were assessed using LC-MS analysis, and the release of indicators for mineralization of fluoride ions was determined by ion chromatography. In a model experiment for bioaugmentation of microorganisms in artificially contaminated soil, the degradation of PFCAs by the association of pseudomonads also occurred faster and deeper than by the individual strains, achieving a degree of biodestruction of 75% over 60 days, with perfluoropentanoic acid being the main metabolite of destruction. Thus, it has been demonstrated that strains of Pseudomonas bacteria with genetic potential for the biodegradation of PFCAs are capable of realizing this potential in association, exhibiting an additive effect.

The aim of this study was to isolate and investigate enzymes involved in the biodegradation of perfluorocarboxylic acids (PFCAs) in Pseudomonas plecoglossicida strain 2,4-D and Pseudomonas mosselii strain 5(3). In this research, enzymes from these strains were concentrated from the culture medium by ultrafiltration and ammonium sulfate precipitation, followed by purification through size-exclusion chromatography. The enzyme activity after ultrafiltration was higher Enzymes from strain 2,4-D released 2 ppm of fluoride ions after 24 hours, increasing to 40,7 ppm after 48 hours. For strain 5(3), fluoride release reached 3 ppm at 24 hours and 46 ppm at 48 hours, confirming the activity of the isolated dehalogenases and their ability to degrade PFCAs. Size-exclusion chromatography revealed that the molecular weight of enzymes from strain 5(3) is approximately 80 kDa, while for strain 2,4-D, it is 76 kDa. The study of these enzymes holds both applied significance for environmental remediation technology development and fundamental importance. Understanding the molecular structure and mechanisms of dehalogenase activity not only provides insights into the cleavage of robust C-F bonds but also sheds light on enzyme evolution as a whole.

A method for optimizing the cultivation of Enterobacter ludwigii BLK and the treatment of wheat plants using a preparation based on this bacterium is proposed. By reducing the concentration of peptone and partially replacing it with an alternative nitrogen source – yeast extract – in the culture medium, the cost of producing the drug was reduced without reducing its effectiveness. It was found that the preparation, produced in a modified environment, activated root growth and promoted the accumulation of chlorophyll in bread wheat leaves. The stimulating effect was more pronounced with a combination of pre-sowing and post-emergence treatment.

The results of the selection of new plant growth-promoting bacteria resistant to herbicides of different chemical structure are presented. Two methods were used for screening: sowing on microbiological media from freshly sampled soil and obtaining enrichment cultures from soil samples exposed to herbicides for a month at a temperature of 28 °C. Inoculation was carried out on selective nutrient media containing herbicides Octapon extra (2,5 g/l), Florax (2,5 g/l), Dicamba (1 g/l), Nanomet (1 g/l), Spetsnaz (1 g/l) or Chistalan (2,5 g/l). These herbicides are commonly used to control weeds in wheat crops. The isolated microorganisms belong to the genus Pseudomonas, fix nitrogen, mobilize phosphates, synthesize phytohormones and antimicrobial compounds. They also can mitigate pesticide stress of crops. An anti-stress biological product containing them has been developed and tentatively named "AGROBIOLOG". For its production, the optimal composition of the nutrient medium and the conditions for industrial submerged cultivation on reactors of various volumes were determined. In the laboratory fermenter FA10 with a volume of 10 liters after 72 hours of cultivation at a temperature of 28 °C, a stirrer speed of 200 rpm, aeration of 0.5 volumes of air per 1 min per 1 volume of medium, the amount of viable cells was 28 billion CFU/ml of culture liquid. Cultivation on biological reactors with a volume of 1000 liters under the same conditions allowed to achieve a titer of 6.0 billion CFU/ml of culture liquid.