Mikrobiolohichnyi zhurnal最新文献

{"title":"Гуанідінійвмісний олігомер як інгібітор мікробної корозії металу","authors":"D.R. Abdulina, M.Ya. Vortman, Zh.P. Kopteva, G.O. Iutynska, A.E. Kopteva, V.N. Lemeshko, V. V. Shevchenko, L. Biliavska","doi":"10.15407/microbiolj86.01.014","DOIUrl":"https://doi.org/10.15407/microbiolj86.01.014","url":null,"abstract":"Guanidinium-containing oligomers, a poorly studied class of organic compounds, have attracted attention due to their bactericidal properties. A guanidinium-containing oligomer based on an aliphatic oligoepoxide is a newly synthesized substance with bactericidal activity, which gives it the prospects for use as a microbial corrosion inhibitor. Aim. The goal of the study was to synthesize oligomeric alkyl substituted guanidinium bromide and study of its anticorrosive properties in the presence of steel under the influence of corrosive active sulfate-reducing bacteria. Methods. The guanidine-containing alkyl substituted oligomer was obtained by the reaction of the aliphatic oligoepoxide DEG-1 with guanidine, followed by interaction with alkyl bromide. The anticorrosive properties of the guanidine-containing oligomer were studied using collection strains of sulfate-reducing bacteria: UCM B-11503 Desulfovibrio sp.10, UCM B-11501 Desulfovibrio desulfuricans DSM642, and UCM B-11502 Desulfovibrio vulgaris DSM644. The sulfate-reducing bacteria were grown on Postgate В medium for 14 days at a temperature of 28 ± 2 °C. The number of bacteria was determined by the method of tenfold dilution. The corrosion rate was determined by the gravimetric method. The physicochemical parameters of pH and redox potential of the bacterial culture liquid were studied by the potentiometric method. The accumulation of hydrogen sulfide in the culture liquid was determined by the iodometric method. Lipolytic activity was studied spectrophotometrically using a KFK-3 device by reaction with p-nitrophenyl palmitate, catalase activity — using 0.03% hydrogen peroxide, which formed a stable colored complex with a 4% molybdenum diphosphate solution. The specific activity of the studied enzymes was expressed as unit ∙ mg-1 protein. Protein was determined in the supernatant by the conventional Lowry method. Results. It was shown that the oligomer based on aliphatic oligoepoxide has biocidal properties. A significant inhibition of the development of sulfate-reducing bacteria (SRB) was observed after the oligomer was added; only dozens of bacterial cells were detected in the medium after the exposure period. The corrosion rate of steel in the presence of SBR without addition of inhibitors was 0.15 — 0.35 mg/cm2∙h. The addition of DPC (a quaternary ammonium compound based on N-decylpyridinium chloride) (Kyiv Polytechnic Institute (KPI), Ukraine) to the culture medium led to a decrease in the steel corrosion rate to 0.032 — 0.047 mg ∙ cm-2  h-1 (by 6.5—10.6 times). In the presence of Armohib CI-28 inhibitor (based on Diamine Ethoxylate) (Akzonobel, Holland), the corrosion rate was reduced to 0.02—0.039 mg ∙ cm-2  h-1 (by 4.2 — 12.7 times). The addition of guanidinium-containing oligomer to the medium with bacteria reduced the corrosion rate to 0.075—0.079 mg/cm2 ∙ h (by 2.5—2.7 times). According to the mass loss of steel samples, the degree of metal protection against microbial corrosion in","PeriodicalId":18628,"journal":{"name":"Mikrobiolohichnyi zhurnal","volume":"33 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139957204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Вивчення життєздатних бактеріофагів за допомогою активації псевдолізогенного стану Pectobacterium carotovorum","authors":"L.V. Romaniuk, M.A. Zlatohurska, T.Yu. Gorb, F.I. Tovkach","doi":"10.15407/microbiolj86.01.051","DOIUrl":"https://doi.org/10.15407/microbiolj86.01.051","url":null,"abstract":"The rare occurrence of viable bacteriophages is an issue in studying bacterial-phage systems of the phytopathogenic bacterium Pectobacterium carotovorum subsp. carotovorum (Pcc). Aim. To obtain viable bacteriophages by activating pseudolysogeny of the Pcc strains. Methods. To obtain bacteriophage F66, isogenic clones of Nalr mutants of strains Pcc 66A and Pcc M2-4 were used. To study the properties of the phage, ultracentrifugation of viral particles, electron microscopy, electrophoretic separation, and comparative restriction analysis of virion DNA were used. Results. It was shown that some isogenic clones of Nalr -mutants of Pcc 66A and Pcc M2-4 can produce viable bacteriophages under conditions of intensive aeration. At the same time, induced phages are able to reproduce on the parent bacterial strains, which they were isolated from (pseudolysogenic response). A pure line was obtained for the phage isolate induced from pseudolysogenic Pcc 66A Nalr by consecutive single colony passages. This phage, named F66, was shown to be temperate and able to lyse and lysogenize strains of pectolytic bacteria isolated from soft rot affected potato tubers. Phage F66 has а virion with the A1 morphotype characterized by an isometric head with an average diameter of 52.0 ± 2.1 nm and a contractile tail with a length of 115.4 ± 3.2 nm. Showing low stability under environmental conditions, phage F66 differs significantly from the temperate phage ZF40 P. carotovorum, which has a similar virion morphology. Compared phages also differ in the restriction fragment patterns obtained using endonucleases HindIII, BamHI, and HpaI. Conclusions. Temperate phage F66 is a novel P. carotovorum virus. The method for activating the pseudolysogenic state proposed in the article is useful for obtaining viruses of phytopathogenic bacteria.","PeriodicalId":18628,"journal":{"name":"Mikrobiolohichnyi zhurnal","volume":"16 24","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140436634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Активні компоненти флавоноїдного складу «Протефлазид» гальмують репродукцію вірусу грипу: можливі молекулярні мішені взаємодії","authors":"M.A. Arkhypova, L. G. Palchykovska, M.O. Platonov, M.P. Zavelevich, O. M. Deriabin, V.P. Atamaniuk, D.B. Starosyla, S. L. Rybalko","doi":"10.15407/microbiolj86.01.026","DOIUrl":"https://doi.org/10.15407/microbiolj86.01.026","url":null,"abstract":"The search for substances possessing antiviral activities, in particular anti-influenza activity, is of importance for designing new drugs that may be effective in combating viral infections. The antiviral substances of the natural origin such as flavonoids and their derivatives are in the focus of numerous studies. The topical problem is the elucidation of the mechanisms of the interaction between flavonoid substances and the virus-specific targets in infected cells. Aim. To assess the activity of the flavonoid-enriched composition containing the biologically active substances of Proteflazidum against influenza virus in vitro and in vivo and to analyze in silico the putative interactions of the flavonoid components of the composition with PB2 subunit of viral RNA-polymerase. Methods. The anti-influenza effects of flavonoid-enriched composition prepared from the extracts of Deschampsia caespitosa L. and Calamagrostis epigeios L. were assessed in vitro in MDCK cells and in vivo in white outbred mice. Virion RNA was analyzed by RT-PCR with the primers detecting the transcripts of PB1 and PB2 subunits of viral RNA-polymerase and hemagglutinin. The potential interaction of the representative flavonoids of the composition with PB2 subunit of RNA-polymerase was analyzed in silico by molecular docking. Results. The composition under study inhibits effectively replication of А/FM/1/47 (H1N1) strain of influenza virus in vitro and protects the mice against flu infection both in therapeutic and preventive modes of its administration. According to the molecular docking findings, all three major flavonoid compounds of the composition, quercetin, luteolin, and apigenin, interact similarly with the PB2 domain of viral RNA-polymerase. Conclusions. The flavonoid composition containing the biologically active substances of Proteflazidum could be considered as the anti-flu drug with the PB2 subunit of viral RNA-polymerase being one of its potential molecular targets.","PeriodicalId":18628,"journal":{"name":"Mikrobiolohichnyi zhurnal","volume":"154 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140438187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Xanthomonas fuscans subsp. fuscans — a Pathogen of Small Brown Spot of Legumes","authors":"Т.Т. Гнатюк, Н.В. Житкевич, В.П. Патика","doi":"10.15407/microbiolj86.01.057","DOIUrl":"https://doi.org/10.15407/microbiolj86.01.057","url":null,"abstract":"Xanthomonas fuscans subsp. fuscans is known as an obligate phytopathogen — the pathogen of small brown spot of beans that gradually expands the range of host plants and spreads worldwide on legumes. The review provides data on the problems of the pathogen’s systematics and its change depending on the new research and improvement of methods for studying biological properties. Historical data on the first stages of isolation of X. fuscans subsp. fuscans from bean and new stages of its spread and isolation from soybean in Ukraine, after which the pathogen moved from the monophage to polyphage status within the same plant family. The importance of X. fuscans subsp. fuscans as a potentially dangerous phytopathogen, as evidenced by the presence of its samples in many collections of living microorganisms in the world and the quarantine status of the pathogen in a number of European countries are underlined. It has been shown that the phytopathogen X. fuscans subsp. fuscans does not differ significantly from other xanthomonads in terms of its cultural, morphological, physiological, and biochemical properties, especially those that cause diseases of leguminous plants. At the same time, the only but the main feature of this bacterial culture is emphasized — the increased amount and activity of the intracellular enzyme tyrosinase, which distinguishes X. fuscans from all other bacterial phytopathogens and not only among xanthomonads. The variants of the stage of synthesis of tyrosinase and melanin in bacteria, due to which the black-brown pigment is formed, and the lack of research on the pathway of tyrosinase synthesis in phytopathogenic bacteria, in particular X. fuscans subsp. fuscans, are analized. The data on genotypic properties of X. fuscans subsp. fuscans, its affinity with other pathogens of the genus Xanthomonas that cause diseases of leguminous plants, and the possible role of the phenomenon of «horizontal gene transfer» in their affinity along with differences in biological properties are considered. The analyzed literature indicates the potential danger of the causative agent of small brown spot of legumes and the need for constant monitoring of the spread and study of its biological properties to develop methods for controling the spread of X. fuscans subsp. fuscans.","PeriodicalId":18628,"journal":{"name":"Mikrobiolohichnyi zhurnal","volume":"36 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139957303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Характеристика генів інтегронів клінічних ізолятів Pseudomonas aeruginosa, які реалізують резистентність до антибіотиків та біоплівкоутворення цими штамами","authors":"A.F. Alfarras, W.A. Al-Daraghi","doi":"10.15407/microbiolj86.01.003","DOIUrl":"https://doi.org/10.15407/microbiolj86.01.003","url":null,"abstract":"Pseudomonas aeruginosa is a bacterium that holds significant clinical and epidemiological significance. It serves as the principal etiological cause of opportunistic infections in individuals with impaired immune systems. Integrons are known to have a notable impact on Gram-negative bacteria, particularly in the context of P. aeruginosa, a bacterium recognized for its ability to develop resistance to antimicrobial drugs. Aim. To systematically characterize and detect integron genes (intI, intII, intIII) with antibiotic-resistant and biofilm-forming capabilities in isolated P. aeruginosa. Methods. A total of 209 samples were collected from Al Yarmouk Teaching Hospital in Baghdad City, Iraq to isolate P. aeruginosa. The process of bacterial identification was carried out phenotypically and by biochemical tests. Antibiotic susceptibility was measured using the Vitek2 system. Biofilm quantification was done by the microtiter method. The PCR approach was employed to assess the presence of class 1, 2, and 3 integrons. Results. P. aeruginosa was identified in 83 isolates by using a combination of morphological and biochemical examinations where all isolates showed the ability to grow a selective medium on cetrimide agar for P. aeruginosa. The results also showed significant variances (p < 0.05) among the percentage of a number of samples and isolated P. aeruginosa. The burn and wound infection scored the highest percentages (25% and 19%) based on the positivity of P. aeruginosa, whereas burn and ear sites scored the highest percentage (58% and 50%). Also, the isolates show the ability to form biofilm at a percentage of 68.7% with resistance to a high number of antibiotics. The multidrug-resistant and sensitive P. aeruginosa isolates scored high percentages (49.4% and 34.9%) whereas potentially pan drug-resistant and extensively drug-resistant isolates scored low percentages (2.4% and 13.3%). PCR results showed that integron I scored the highest percentage (100%) compared to integron 2 found in 3 (10%) isolates, and no intI3 gene was detected in any of the P. aeruginosa isolates. Conclusions. Overall, the findings of the present investigation indicate that integrons and biofilm development are recognized as significant factors contributing to antibiotic resistance in P. aeruginosa. The prevalence of class 1 integrons is shown to be significantly high in all bacterial isolates, with a complete occurrence rate of 100%. This high incidence of class 1 integrons is associated with the development of resistance to crucial antibiotics, including β-lactams, aminoglycosides, and cephalosporins.","PeriodicalId":18628,"journal":{"name":"Mikrobiolohichnyi zhurnal","volume":"31 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140435976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phenotypic and Genotypic Criteria for the Screening of Highly Active S-Type Pyocins Pseudomonas aeruginosa Producers","authors":"O. B. Balko, L.B. Zelena, O. Balko, N.A. Bobyr, V. Voitsekhovsky, L. Avdeeva","doi":"10.15407/microbiolj86.01.039","DOIUrl":"https://doi.org/10.15407/microbiolj86.01.039","url":null,"abstract":"Bacteriocins of Pseudomonas aeruginosa, especially S-type pyocins, show high efficiency as analogs of antimicrobial drugs. Various screening methods can be used to identify producers of highly active pyocins, but there are no clear criteria for selecting perspective strains. The aim of this work was to determine criteria that can be used during phenotypic and genotypic screening for the selection of perspective highly active S-type pyocin P. aeruginosa producers. Methods. The objects of investigation were 40 P. aeruginosa strains. Pyocins were obtained from each culture, relative coefficients of activity spectrum and sensitivity were determined for all the strains used. The obtained results of the phenotypic screening were compared with the data of the genotypic screening. Results. The use of the proposed method of activity assessment according to the lysis intensity made it possible to phenotypically assess the expression of pyocin genes. It was established that according to the new criteria, only one strain — P. aeruginosa UCM B-333 — can be included in the group of the most active pyocin producers that inhibit the growth of more than 75% of indicator cultures. The majority of representatives of maximally and highly active producers were characterized by high resistance to the action of other pyocins, which can be considered as an additional criterion for the selection of perspective strains. During genotypic screening, it was established that the quantity of pyocin genes in the genome cannot be interpreted as a clear criterion of the producer’s perspective. However, 50% of representatives of maximally and highly active pyocin producers were characterized by the presence of two pyocin genes, while in 47.7% of moderately active and 54.5% of low active producers, one pyocin gene was detected more often. It was established that with widening the bacteriocin activity spectrum, the detection frequency of pyocin S1 and S5 genes increases, and for pyocin S2 and S3 genes — decreases. Thus, among the producers of maximally and highly active bacteriocins, pyocin S1 and S5 genes were identified with the highest frequency — 42.8% and 78.6%, and pyocin S2 and S3 genes — with the lowest one — 28.6% and 7.1%, respectively. Gene of pyocin S4 with tRNase activity were detected with equally high frequency in all groups of producers. Conclusions. The method of activity assessment by the lysis intensity allows not only to determine the presence of pyocins, but also to phenotypically evaluate the level of their expression, which is an important criterion for the selection of perspective producers. Bacteriocins with a wider activity spectrum are synthesized by P. aeruginosa strains with higher resistance to the action of pyocins from other cultures. The most optimal genotypic criterion for the selection of a highly perspective pyocin producer, detection of genes combination of bacteriocins with different mechanisms of action — with DNase activity (pyocin S1) and the","PeriodicalId":18628,"journal":{"name":"Mikrobiolohichnyi zhurnal","volume":"34 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140435750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Роль бактерій як основи пелагічних харчових ланцюгів в ультраоліготрофних північних патагонських озерах: міні-огляд","authors":"Patricio De los Ríos-Escalante","doi":"10.15407/microbiolj86.01.066","DOIUrl":"https://doi.org/10.15407/microbiolj86.01.066","url":null,"abstract":"The northern Patagonian lakes are located in the South American Andes between 38—41° of Argentina and Chile. In their original stage, these lakes were described as ultraoligotrophic due the presence of perennial native forest that avoided the nutrients inputs from surrounding basin. The first studies described low phytoplankton abundances, but in recent studies, the presence of mixotrophic ciliates has been reported that may be a basis on trophic webs under the ultraoligotrophic status. They can graze on heterotrophic bacteria and nannoflagellates and can also do photosynthesis. Under the ultraoligotrophic status, the bacteria would have the basis on pelagial food webs because these would be grazed by zooplankton and mixotrophic ciliates. Nevertheless, when the lakes have a transition from oligotrophy to mesotrophy, although the bacterial biomass increases, they would not have an exclusive role because of a complex interaction between phytoplankton and grazer zooplankton.","PeriodicalId":18628,"journal":{"name":"Mikrobiolohichnyi zhurnal","volume":"10 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140435676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Encapsulated Probiotic Microorganisms in Functional Food Products","authors":"S. Starovoitova, K. Kishko, O.M. Demchenko, V.V. Bila","doi":"10.15407/microbiolj85.06.077","DOIUrl":"https://doi.org/10.15407/microbiolj85.06.077","url":null,"abstract":"Alterations in the composition of the gut microbiota are associated with a wide range of pathologies, including not only inflammatory diseases of the gastrointestinal tract, but also diabetes, obesity, cancer, and diseases of the cardiovascular and central nervous systems. With an imbalance of the microbiota (dysbiosis), there is increased intestinal permeability and a violation of local or systemic immune responses. One of the possible ways to improve intestinal microbiota is the use of dietary supplements and functional food products enriched with highly effective encapsulated probiotic microorganisms, as well as prebiotic compounds. Such products contribute to the restoration of normal intestinal microflora and its integrity, and also indirectly affect the positive outcome in the treatment of many pathological conditions mediated by an imbalance in the intestinal microbiota. Maintaining the activity of probiotics in food carriers or functional food products designed for the prevention and complex therapy of various pathological conditions is important both for the normalization of the intestinal microflora and the health of the body as a whole. In this context, encapsulation is an effective approach to maintain the viability and stability of probiotics under adverse conditions in the gastrointestinal tract and also an effective way to protect from processing conditions, temperature, and transportation. The development of functional nutrition products enriched with highly effective encapsulated probiotic microorganisms is a priority for new research in the field of prevention and treatment in microbiota-targeted therapy. The use of such products is based on the conception of 3p — pathophysiology-based individualized use of probiotics and prebiotics in various pathological conditions mediated by a violation of the qualitative and/or quantitative composition of the intestinal microbiota: implementing a predictive, preventive, and personalized medical approach.","PeriodicalId":18628,"journal":{"name":"Mikrobiolohichnyi zhurnal","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138951269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Proteolytic Activity of Bacillus Strains Isolated from Soil of Rice Agrocenosis","authors":"O. Gudzenko, L. Varbanets, K. V. Avdiyuk, L. Pasichnyk","doi":"10.15407/microbiolj85.06.041","DOIUrl":"https://doi.org/10.15407/microbiolj85.06.041","url":null,"abstract":"Microorganisms are the most common sources of commercial enzymes due to their physiological and biochemical properties, facile culture conditions, and ease of cell manipulation. Among microbial enzymes, proteases are ubiquitous in nature and have been found in all living forms encompassing the eukaryotes like plants, animals, fungi, and protists as well as the prokaryotic domains of bacteria and archaea. Proteases are the most important for the industry and constitute approximately 60% of the total industrial enzyme market. Among the bacteria, the genus Bacillus has a very prominent place in terms of the commercial production of proteases. Earlier from the water and bottom sediments of the Black Sea, we have isolated a number of producers of proteolytic enzymes from Bacillus species. The aim of this work was to investigate the ability of representatives of a number of soil bacilli species to synthesize enzymes that hydrolyze such protein substrates as elastin, fibrin, fibrinogen, and keratin. Methods. The objects of the study were 8 cultures (KS 1 — KS 8) isolated from the soil of the rice agrocenosis. Cultures were grown under conditions of deep cultivation at 28 °С, with a mixing speed of for the nutrient medium of 230 rpm for 4 days. Methods of determining proteolytic (caseinolytic, elastolytic, fibrinolytic, fibrinogenolytic, and keratinase) activity in the culture liquid supernatant were used. Disulfide reductase activity was measured spectrophotometrically at 412 nm by evaluating the yellow sulfide formed during the reduction of 5,5’-dithiobis-(2-nitrobenzoic acid) (DTNB). Results. The study of the spectrum of proteolytic activities of 8 freshly isolated strains showed that only KS 6 under experimental conditions did not show the ability to hydrolyze any of the studied substrates (casein, elastin, fibrin, fibrinogen, and keratin). Strains KS 1, KS 2, KS 7, and KS 8 showed higher levels of activity compared to other strains studied. The most interesting for further research are: І) strain KS 1, which showed the highest fibrinolytic activity, ІІ) strain KS 2 as the most effective producer with elastase and fibrinogenolytic activity, III) KS 7 and KS 8, which simultaneously showed the highest rates as keratinase (7 U/mL and 9 U/mL) and sulfate reductase (33 μmol/min and 31 μmol/min) activity, respectively. Conclusions. According to the catalytic properties, a number of representatives of Bacillus, isolated from the soil of the rice agrocenosis may be promising for further research as an enzyme producer with proteolytic activity.","PeriodicalId":18628,"journal":{"name":"Mikrobiolohichnyi zhurnal","volume":"38 19","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138948790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular Profile of Metallo-β-Lactamase Producing Bacterial Isolates from Clinical Samples; South-South Nigeria Perspective","authors":"U.E. Akereuke, I.A. Onwuezobe, A.E. Ekuma, E.N. Edem, N.S. Uko, R.S. Okon, E.O. Bawonda, E.N. Ekpenyong","doi":"10.15407/microbiolj85.06.015","DOIUrl":"https://doi.org/10.15407/microbiolj85.06.015","url":null,"abstract":"One of the major clinical problems regarding β-lactam antibiotics resistance is attributed to metallo-beta-lactamases (MβL), which are a group of enzymes that is a subset of beta- lactamases belonging to group B of the Ambler classification, which causes hydrolysis of carbapenems. The study was conducted to check the prevalence of MβL and its genes (IMP, VIM, and NDM) among Gram-negative isolates. Methods. 312 clinical samples (urine and wound) were cultured, and antimicrobial susceptibility testing was performed using the conventional disk diffusion method. MβL-phenotypic detection was uncovered by standard bacteriological techniques, MβL genes were amplified using pre-determined conditions set on an AB19700 Applied Biosystem thermal cycler. Results. 157 (56.1%) Gram-negative and 123 (43.9%) Gram-positive were isolated. Escherichia coli 32 (11.4%) and Pseudomonas aeruginosa 32 (11.4%) were the most predominant. Providencia stuartii 3 (1.1%), Klebsiella ornitholytica 2 (0.7%), and Stenotrophomonas maltophilia 1 (0.4%) were some of the less predominant isolates. Imipenem and Ertapenem were the most sensitive, while Gentamicin, Amoxicillin-Clavulanate, and Ceftriaxone were the most resistant. Twelve species (7.6%) were identified as MβL producers. The VIM gene (12: 100%) was the predominant gene, followed by the NDM gene (6: 50%) and the IMP gene (2: 16.7%). Conclusions. The detection of blaVIM, blaNDM, and blaIMP genes in South-south Uyo is really worrisome, and proper infectious control measures should be taken in order to prevent outbreaks of MβL-producing Gram-negative bacteria isolated in Uyo, South South Nigeria.","PeriodicalId":18628,"journal":{"name":"Mikrobiolohichnyi zhurnal","volume":"26 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138950847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}