Search

The aim of the work was to obtain a producer strain with increased lysine accumulation using the chemical mutagenesis method. Methods. To achieve the goal, we used the method of treating the lysine-producing strain with the chemical mutagen N-methyl-N-nitro-N-nitrosoguanidine, cultivating the resulting clone and determining the accumulation of lysine in flasks and a bioreactor. Results. The optimal concentrations and duration of mutagen action for the production of mutant microorganisms were found. Сlones with the maximum lysine accumulation were selected. Mutagenesis was carried out consecutively three times. As a result, lysine-producing strain Brevibacterium sp. IMV B-7796 auxotrophic regarding leucine and threonine with maximum accumulation of the target amino acid was obtained. Conclusions. The lysine producer Brevibacterium sp. IMV B-7796 was obtained, which produced 65.0 g/dm3 of lysine in a bioreactor under conditions of periodic cultivation with feeding. The Brevibacterium sp. IMV B-7796 strain was proposed as a basis for the creation of a genetically modified strain with increased accumulation of lysine for further use in industrial lysine technology.

The aim of this work was to enlarge accumulation of butanol from switchgrass Panicum virgatum L. biomass using strains-producers obtained from grounds and silts of Kyiv lakes. The objects of the study were strains of C. acetobutylicum ІМВ B-7407 (IFBG C6H), Clostridium acetobutylicum IFBG C6H 5М and Clostridium tyrobutyricum IFBG C4B from the "Collections of microbial strains and lines of plants for food and agricultural biotechnology" of the Public Institution "Institute of Food Biotechnology and Genomics" of the National Academy of Sciences of Ukraine. Gas chromatography was used to determine the alcohol concentration at the stage of solvent synthesis. To determine the effect of butanol precursors during cultivation, butyric, lactic and acetic acids were used. Optimization of processing parameters, which was based on the needs of cultures, allowed us to increase the yield by 20 and 50% for the initial and mutant strain respectively. Using synthetic precursors (such as lactic, butyric and acetic acid) during cultivation increased total concentration of butanol by 1.7 times. To optimize the process, a study was carried out using acetone- butyl grains. Using of acetone-butyl grains in concentrations up to 60% does not affect the synthesis of butanol by C. acetobutylicum IFBG C6H 5M. Increasing the concentration of grains led to decrease in accumulation of butanol. Almost double increase in accumulation of the target product (butanol) was achieved using two-stage fermentation and/or precursors of synthesis. It was shown the possibility of using acetone-butyl grains in fermentation. As a result the mass fraction of the waste was reduced.

The purpose of our work was to study generic and specific affinity of domestic strainsproducers, comparative productivity butanol strains-producers screening, fermentation of sugars being a part of renewable lignocelluloses raw materials and to determine the conditions for the butanol yield increasing. The objects of research were strains Clostridium acetobutylicum ІМВ В-7407 (IFBG C6H), IFBG C4B and IFBG C7P from «Collection microorganism’s stains and plants line for food and agriculture biotechnology» of Institute of Food Biotechnology and Genomics of the National Academy of Sciences of Ukraine. It was determined that domestic butanol-producing strains were relatively more productive and might be promising for improvement technology of butanol production.

Biobutanol is one of the types of biofuels produced using microbial synthesis (acetone–butanol–ethanol fermentation). It is possible to increase the level of accumulation of the target product due to metabolic changes in producer cells under the influence of stress factors. For this purpose, the effect of such stress factors as allopurinol, furfural, zinc, and oxygen, as well as glycerol as a nonspecific substrate on the functioning of Clostridium sp. cells, was studied. It was demonstrated that the butanol concentration was the highest (1.2 g/L) as compared with the control (0.6 g/L) when adding 0.5 g/L of furfural to the culture medium. The use of ZnSO4 at a concentration of 0.001 g/L increased the butanol concentration to 1.1 g/L, and the highest butanol concentration (1.3 g/L) was obtained when using glucose and glycerol as carbon sources in a ratio of 1 : 3. The butanol concentration in the culture medium increased to 0.8 g/L with the addition of 0.025 g/L of allopurinol. The possibility of using the above-mentioned stress factors to increase the accumulation of the target product by influencing the metabolic pathways in microorganism cells is substantiated. [ABSTRACT FROM AUTHOR]

Aim. The purpose of the study was to investigate the effect of ultrasonic disintegration on the lignocellulosic raw materials (biomass of the non-cereal part of rape) with its subsequent use as a substrate for the production of biobutanol. Methods. Butanol-producing strains and the biomass of the non-cereal part of rape Brassica napus were used in the present study. Ultrasonic disintegration of lignocellulosic raw materials was performed on the specially designed equipment. Results. The effect of ultrasonic disintegration on lignocellulosic raw materials was investigated for further application in biofuel production based on microbiological conversion. The possibility of using the obtained components after the pre-treatment of lignocellulose by ultrasonic disintegration as a substrate for the microbiological synthesis of butanol was shown. The highest accumulation of butanol (2.4 g/l) was obtained with the use of 5% dry matter content in the medium, 5 min treatment and the specific power of ultrasonic disintegration of 0.72 W/ml. Conclusions. The possibility of producer strains of the genus Clostridium to use cellulose in the fermentation process has been shown. When using ultrasonic disintegration for pretreatment of the non-cereal part of the biomass of rape, the accumulation of butanol increased by 3 folds. [ABSTRACT FROM AUTHOR]

The aim of the work was to investigate the accumulation of butanol by Clostridium strain producers using meshed green rape biomass as substrate. The accumulation of butanol by producer strains was studied using rape as substrate in the doses of 5-30 g/l. The cells were precipitated in an ultracentrifuge, the supernatant was distilled, and fermentation products were determined. The presence of solvents in the culture fluid was determined by gas chromatography. The biggest accumulation of butanol was produced by the strain Clostridium sp. IMB B-7570 on 2.3 g/l mashed switchgrass biomass. The optimal inoculum concentration for maximum accumulation of butanol using switchgrass biomass was 10% of the volume of fermentation liquid. The greatest accumulation of butanol (2.9 g/l) was obtained in optimal culture conditions and at 10 g/l dry switchgrass biomass in the fermentation medium. Thus, the present study showed that mashed switchgrass biomass was assimilated by Clostridium sp. strains. The accumulation of butanol depended on Clostridium strain, the amount of inoculum, the concentration and degree of grinding of the substrate. [ABSTRACT FROM AUTHOR]

Literary data on the organization of the genome, the connection of genes with the production and regulation of solvents, and the metabolic engineering of solventogenic clostridia are presented. The transition from the phase of the formation of acids to the phase of the formation of alcohols and the relationship of the latter with sporogenesis were analyzed. The main key genes (ak, pta, buk, ptb, thl, crt, bcd, BdhAB, ctfAB, adc, rub, Spo0A, adhE, hdb) that affect their course were identified. The possibility of improving strains by genetic manipulations (inactivation of genes, entering of genes of other microorganisms, etc.) was shown. The effect of gene inactivation on solvent production was described. An analysis of methods for increasing the accumulation of butanol showed the need to create effective recombinant producer strains for butanol supra synthesis using renewable raw materials. [ABSTRACT FROM AUTHOR]

The aim of the investigation of the effect of the explosive autohydrolysis on lignocellulosic biomass (saving, switchgrass biomass) for consequent use as a substrate to produce biofuels such as butanol. Butanol-producing strains, switchgrass Panicum virgatum L. biomass and its components after autohydrolysis were used in the study. The thermobaric pressure pretreatment of lignocellulosic biomass was carried out using specially designed equipment. The effect of explosive autohydrolysis on lignocellulosic biomass for further use in producing biofuels using microbial conversion was studied. Components of lignocellulosic biomass were fractionated after undergoing thermobaric treatment. The possibility of using different raw material components after using explosive autohydrolysis processing to produce biobutanol was found. Products of switchgrass biomass autohydrolysis were shown to need further before fermentation purification from furfural formed by thermobaric pretreatment and inhibiting the growth of microorganisms. The ability of strains of the genus Clostridium to use cellulose as a substrate for fermentation was proved. It was found that using explosive autohydrolysis pretreatment to savings allowed to boost the butanol accumulation by 2 times. [ABSTRACT FROM AUTHOR]

The leading pathological mechanisms of Alzheimer's disease are amyloidosis and inflammation. The presented work was aimed to study the effect of human peripheral blood mononuclear cells (hPBMcs) cells-matrix adhesion on their pro-inflammatory state in vitro . Although direct interaction of Аβ42 to PBMC is not a cellular model of Alzheimer's disease, PBMCs may serve as test cells to detect Аβ42-dependent molecular effects in monitoring disease progression. Peripheral blood mononuclear cells (PBMCs) are used to assess changes in cytokines released in response to diseases or Alzheimer's disease-specific cytotoxic molecules such as Aβ42. The effect of recombinant amyloid β-peptide rАβ42 on the concentration of endogenous amyloid β-peptide Aβ40 and pro-inflammatory cytokines TNFα and IL-1β in human peripheral blood mononuclear cells that were cultured in suspension and immobilized in alginate microcarriers for 24 h were investigated. The localization and accumulation of Aβ40 and rAβ42 peptides in cells, as well as quantitative determination of the concentration of Aβ40 peptide, TNFα and IL-1β cytokines, was performed by intravital fluorescence imaging. The results were qualitatively similar for both cell models. It was determined that the content of TNFα and Aβ40 in the absence of rAβ42 in the incubation medium did not change for 24 h after incubation, and the content of IL-1β was lower compared to the cells that were not incubated. Incubation of cells in vitro with exogenous rAβ42 led to an increase in the intracellular content of TNFα and Aβ40, and no accumulation of IL-1β in cells was observed. The accumulation of Aβ40 in the cytoplasm was accompanied by the aggregation of rAβ42 on the outer surface of the cell plasma membrane. It was shown that the basic levels of indicators and the intensity of the response of immobilized cells to an exogenous stimulus were significantly greater than those of cells in suspension. To explore whether non-neuronal cells effects in alginate microcarriers were cell-matrix adhesion mediated, we tested the effect of blocking β1 integrins on proamyloidogenic and proinflammation cellular state. Immobilization within alginate hydrogels after incubation with the β1 integrins blocking antibodies showed a remarkable inhibition of TNFα and Aβ40 accumulation in rAβ42-treated cells. It can be concluded that activation of signal transduction and synthesizing activity of a portion of mononuclear cells of human peripheral blood is possible (can significantly increase) in the presence of cell-matrix adhesion., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Kot, Kot, Kurbanov, Andriiash, Tigunova, Blume and Shulga.)

Butanol-producing strains Clostridium sp. UCM B-7570 and C. acetobutylicum UCM B-7407 were used for research from "Collection of strains of microorganisms and plant lines for food and agricultural biotechnology" of the Institute of Food Biotechnology and Genomics of the National Academy of Sciences of Ukraine, glycerol (BASF, Germany) and apple pomace (total moisture 4%) after apple juice production. The aim of this work was to study the possibility of using apple pomace by domestic butanol-producing strains of Clostridium sp. UCM B-7570 and C. acetobutylicum UCM B-7407 as a substrate. Producers were cultured on medium with different concentrations of apple pomace, glycerol was used for the inoculation. The presence of ethanol, acetone, and butanol in the culture liquid was determined using a gas chromatograph. It was determined that a significant part of the macrocomponent composition of the extracts can be used in bioconversion by producing strains of the genus Clostridium. It was determined that the highest concentration of butanol (10 g/dm 3 ) was at a concentration of 120 g/dm 3 in the extracts. The obtained data showed the possibility of using apple pomace as a substrate in biobutanol technology., (© 2023. The Author(s).)

The rapid development of new molecular methods and approaches, sequencing technologies, has provided new insights into genetic and structural features of bacterial genomes. Information about the genetic organization of metabolic pathways and their regulatory elements has greatly contributed to the increase in the number of studies related to the construction of new bacterial strains with improved characteristics. In this study, the entire genome of the producing strain Clostridium sp. UCM В-7570 from the "Collection of producing strains of microorganisms and plant lines for food and agricultural biotechnology" of Institute of Food Biotechnology and Genomics of the National Academy of Sciences of Ukraine was sequenced and characterized. The genome was assembled into the scaffold with a total size of 4,470,321 bp and a GC content of 29.7%. The total number of genes identified was 4262, of which 4057 encoded proteins, 10 were rRNA operons, and 80 were tRNA genes. The genes of the sequenced genome encoding enzymes involved in butanol fermentation were found and analyzed. They were organized into cluster structures, and their protein sequences were found to be similar to the corresponding strains of C. acetobutylicum, C. beijerinckii, and C. pasteurianum type strains with the highest similarity to the latter. Thus, Clostridium sp. UCM В-7570 producing strain was identified as C. pasteurianum and suggested for metabolic engineering purposes., (© 2023. The Author(s), under exclusive licence to Institute of Plant Genetics Polish Academy of Sciences.)