Papers by Nadezhda Fursova
Microorganisms, Aug 20, 2022
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Antibiotics and chemoterapy, 2011
Antimicrobial activity of bacteriocin S760 (enterocin) produced by Enterococcusfaecium strain LWP... more Antimicrobial activity of bacteriocin S760 (enterocin) produced by Enterococcusfaecium strain LWP760 was studied. Bacteriocin S760 is a cationic, hydrophobic, and heat stable peptide with the molecular weight of 5.5 kDa and pl of 9.8. Enterocin S760 is shown to inhibit in vitro the growth both of sensitive and resistant to antibacterials gramnegative and grampositive bacteria of 25 species. MICs of the bacteriocin S760 vary between 0.05-1.6 mg/l for Escherichia coli 0157:H117, Salmonella typhimurium, Salmonella enteritidis, Campylobacter jejuni, Yersinia enterocolitica, Yersinia pseudotuberculosis, Listeria monocytogenes and Clostridium perfringens, that are main food-borne pathogens, and from 0.4-1.6 mg/l for Streptococcus pyogenes, Streptococcus pneumoniae and Corynebacterium diphteriae. It is also active against antibioticresistant strains of Staphylococcus aureus, Enterobacter cloacae, Acinetobacter baumannii (with MICs of 0.05-3 mg/l), Klebsiella pneumoniae (with MICs of 6 mg/l), Pseudomonas aeruginosa (with MICs of 0.4-25 mg/1), as well against fungi belonging to species of Candida albicans, Candida krusei and Aspergillus niger (with MICs of 0.1-0.2 mg/l). Enterocin S760 is a novel antimicrobial agents useful in medicine, veterinary and food industry.
Microorganisms, Aug 6, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Probiotics and Antimicrobial Proteins, Dec 1, 2009
The antimicrobial spectra of previously published bacteriocin E 50–52 (39 a.a.; 3,932 Da; pI = 8.... more The antimicrobial spectra of previously published bacteriocin E 50–52 (39 a.a.; 3,932 Da; pI = 8.5) and bacteriocin B 602 (29 a.a.; 3,864 Da; pI = 7.2) were determined. Named peptides were related to class IIa (pediocin-like) bacteriocins. Minimal inhibitory concentrations (MICs) of bacteriocins have been determined for bacterial isolates that were causative agents of nosocomial infections collected from Russian hospitals in 2003–2007, namely methicillin-resistant Staphylococcus aureus (MRSA)
Microbiology resource announcements, Jan 2, 2020
Klebsiella pneumoniae of capsular type K1 is the most common causative agent of both health care-... more Klebsiella pneumoniae of capsular type K1 is the most common causative agent of both health care-associated and community-acquired infections. Here, we report the draft genome sequences of 10 K1-type K. pneumoniae strains isolated from patients in an infectious disease hospital and neurosurgical intensive care unit in Russia. K lebsiella pneumoniae is a well-known opportunistic pathogen that causes community-acquired and health care-associated infections (1, 2). A capsular polysaccharide is the major virulence factor of K. pneumoniae (1, 3). Of the number of documented capsular types, strains of the K1 type, along with those of the K2 type, are the most virulent human pathogens (4, 5). We previously reported genome sequences of 10 strains of the K. pneumoniae K2 type, isolated from patients in an infectious disease hospital and neurosurgical intensive care unit (6). In this study, we report the genome sequences of K1-type K. pneumoniae strains isolated in the same hospitals (7). Bacteria were grown at 37°C on nutrient medium no. 1 (Obolensk, Russia). Genomic DNA was isolated using the phenol-chloroform extraction and ethanol precipitation methods (https://fdocuments.in/download/phenol-chloroform-isoamyl-alcohol-pci-dna-isoamyl-alcohol-pci-dna-extraction). Draft genome sequencing was performed using Nextera XT DNA sample preparation kits, a MiSeq reagent kit v.3 (300 cycles), and the MiSeq platform (Illumina). For each genome, the paired reads without filtering were de novo assembled with Unicycler v.0.4.7 (8). Default parameters were used for all software. The resulting draft genome sizes ranged from 5.52 to 5.81 Mb, with GC contents ranging from 56.9 to 57.2%. The final assemblies were annotated with the NCBI Prokaryotic Genome Annotation Pipeline (9), resulting in the identification of total numbers of genes ranging from 6,147 to 5,453 (Table 1). Raw reads were used for multilocus sequence type (MLST) analysis with MLST v.2.0 (https://cge.cbs.dtu.dk/ services/MLST/). All strains were assigned to sequence type 23. Five types of plasmid replicons were determined in the assembled genomes using PlasmidFinder v.2.1 (10) (Table 1). All of the strains harbored a pLVPK-like virulence plasmid (11) containing an IncHI1B replicon, genes rpmA and/or rmpA2 encoding regulators of the mucoid phenotype specific to hypervirulent K. pneumoniae, and siderophore gene clusters iucABCD, iutA, and iroBCDN. Important differences in antibiotic resistance phenotype and resistance genes between strains with different plasmid profiles were revealed (Table 1). The strains harboring only a pLVPK-like plasmid were resistant to ampicillin, fluoroquinolone, and fosfomycin due to the presence of the chromosomal genes bla SHV-190 , oqxA and/or oqxB, and fosA, respectively. Strain KPB1493 acquired the IncFII(K) plasmid, which additionally carried genes providing resistance to aminoglycosides, phenicols, sulfonamides, trimethoprim, and tetracyclines. Strains KPB3188, KPB1103, KPB475, KPB470, and KPB463-13 harbored the IncL/M plasmid carrying the carbapenemase gene bla OXA-48 and demonstrate resistance to carbapenems. The extrachromosomal genome of strain KPB463-13 and its resistance
Beilstein Journal of Nanotechnology, Jan 23, 2018
BN/Ag hybrid nanomaterials (HNMs) and their possible applications as novel active catalysts and a... more BN/Ag hybrid nanomaterials (HNMs) and their possible applications as novel active catalysts and antibacterial agents are investigated. BN/Ag nanoparticle (NP) hybrids were fabricated using two methods: (i) chemical vapour deposition (CVD) of BN NPs in the presence of Ag vapours, and (ii) ultraviolet (UV) decomposition of AgNO 3 in a suspension of BN NPs. The hybrid microstructures were studied by high-resolution transmission electron microscopy (HRTEM), high-angular dark field scanning TEM imaging paired with energy dispersion X-ray (EDX) mapping, X-ray photoelectron spectroscopy (XPS), and infrared spectroscopy (FTIR). They were also characterized in terms of thermal stability, Ag + ion release, catalytic and antibacterial activities. The materials synthesized via UV decomposition of AgNO 3 demonstrated a much better catalytic activity in comparison to those prepared using the CVD method. The best catalytic characteristics (100% methanol conversion at 350 °C) were achieved using the UV BN/Ag HNMs without preliminary annealing at 600 °C in an oxidizing atmosphere. Both types of the BN/Ag HNMs possess a profound antibacterial effect against Escherichia coli K-261 bacteria.
Медицинский совет, May 13, 2022
Резюме Введение. При увеличении уровня приобретенной антибиотикорезистентности патогенов усложняе... more Резюме Введение. При увеличении уровня приобретенной антибиотикорезистентности патогенов усложняется и замедляется лечение, особенно при инфекциях, ассоциированных с биопленками. Возрастает потребность в разработке и использовании новых антибактериальных препаратов, обладаю щих специфичной антимикробной активностью. Цель-изучить антимикробное действие и динамику формирования устойчивости к бензидамина гидрохлориду у различных инфекционных возбудителей. Материалы и методы. Для получения биопленок микроорганизмы культивировали в плоскодонных культуральных планшетах. Планктонные клетки получали суспендированием и пересевом единичных колоний суточной культуры в плоскодонные культуральные планшеты. Для определения антимикробной активности исследуемых препаратов готовили двукратные разведения и вносили в лунки планшета с бактериальной культурой. Динамику формирования устойчивости к бензидамина гидрохлориду изучали, пассируя культуры в жидкой питательной среде с возрастаю щими с двукратным шагом концентрациями антисептика. После 2-3 дней инкубации из пробирки с максимальной концентрацией препарата, в которой наблюдался бактериальный рост, бактерии пересевали в новые, с более высокими концентрациями препарата. Результаты. Бензидамина гидрохлорид проявлял высокий уровень активности против бактерий M. catarrhalis и дрожжеподобных грибов C. albicans. Чуть меньшая активность препарата отмечена для бактерий видов S. aureus и E. coli. Бензидамина гидрохлорид обладал высоким уровнем антибактериальной активности против предварительно сформированных биопленок. Анализ динамики формирования устойчивости к бензидамина гидрохлориду у микроорганизмов различных видов показал, что возможность формирования такой устойчивости крайне мала. Процесс адаптации наблюдался лишь у E. coli. Исследованные штаммы видов S. aureus, C. albicans и M. catarrhalis не приобрели устойчивости к тестируемому препарату. Выводы. Бензидамина гидрохлорид может быть эффективно использован против множества инфекционных возбудителей лор-инфекций, так как показаны высокий уровень его антибактериальной активности против предварительно сформированных биопленок, различных видов бактерий и дрожжеподобных грибов и крайне низкий уровень возникновения устойчивости. Ключевые слова: бензидамина гидрохлорид, антимикробная активность, резистентность, планктонные бактерии, биопленки Благодарности. Работа выполнена в рамках отраслевой программы НИР Роспотребнадзора.
Molekuliarnaia genetika, mikrobiologiia i virusologiia, 2021
Klinicheskaia laboratornaia diagnostika, Apr 15, 2020
The study is devoted to the study of the antimicrobial activity of the antioxidant dioxidin and t... more The study is devoted to the study of the antimicrobial activity of the antioxidant dioxidin and the complex dioxin-containing preparation Nosolin-ultra, nasal drops against planktonic and biofilm cultures of pathogens of ENT infections, the dynamics of the formation of microbial resistance to dioxidine. 11 reference strains and 9 clinical strains of microorganisms were used in the study: Streptococcus spp., Staphylococcus spp., Micrococcus luteus, Haemophilus influenzae, Acinetobacter pittii, Klebsiella pneumoniae, Moraxella catarrhalis, Pseudomonas aeruginosa. The antimicrobial activity of preparations against planktonic cultures was determined by serial dilution in broth and spot method on solid nutrient media, against biofilms by the applicator method. The dynamics of dioxidine resistance formation was studied by passaging cultures in a liquid nutrient medium with increasing concentrations of antiseptic. Based on the study, it was found that Dioxidin showed antimicrobial activity against plankton cells of all strains (MBC=0.08-5 mg/ml), except S. pyogenes SN345 (MBC>5 mg/ml), inhibited the growth of formed biofilms (MBC=0.08-2.5 mg/ml) of all strains except S. pyogenes SN345 (MBC>5 mg/ml). The drug «Nosolin-ultra, nasal drops» was highly active against plankton cells (MBC=0.04-0.63 mg/ml) and biofilms (MBC=0.02-0.31 mg/ml) of gram-negative bacteria, except A. pittii (MBC>2.5 mg/ml), less active against plankton cells (MBC=1.25-2.5 mg/ml) and biofilms (MBC=0.02-0.31 mg/ml) of gram-positive bacteria and C. albicans. One strain (S. aureus) formed a variant resistant to dioxidine at a concentration of 20 mg/ml, which exceeded the concentration of dioxidine in the complex preparation; other strains (P. aeruginosa, K. pneumoniae, C. albicans) did not form such variants. The data obtained indicate that the drug «Nosolin-ultra, nasal drops» can be effectively used against most pathogens of ENT infections. It is worth noting that with prolonged use of the drug for some types of ENT pathogens in the future, a slight decrease in effectiveness may be noted.
Microbial Drug Resistance, Aug 1, 2020
Aims: The objective of this study was phenotypic and genotypic characterization of antibacterial-... more Aims: The objective of this study was phenotypic and genotypic characterization of antibacterial-resistant Klebsiella pneumoniae clinical strains isolated in Moscow Transplantology Intensive Care Unit in 2017-2019. Results: Major strains among K. pneumoniae (n = 63) isolated from 30 patients were recognized as extensive drug-resistant (n = 55) pathogens, and remaining strains were recognized as multidrug-resistant (n = 8) pathogens. The beta-lactamase genes blaSHV-1,-2a,-11,-27,-67,-187 (n = 63), blaCTX-M-14,-15 (n = 61), blaTEM-1 (n = 54), blaOXA-48 (n = 52), and blaNDM-1 (n = 2), as well as class 1 integrons (n = 19) carried gene cassette arrays aacA4 (n = 2), dfrA1-orfC (n = 6), aadB-aadA1 (n = 9), dfrA15-aadA1 (n = 3), and dfrA12-orfF-aadA2 (n = 1) were identified in the strains. All strains carried four virulence genes: wabG, fimH, uge, and allS, but two strains had additionally kfu gene. Six known sequence types (STs) of K. pneumoniae ST395 (n = 44), ST377 (n = 3), ST307 (n = 4), ST13 (n = 2), ST39 (n = 2), ST3346 (n = 1), and a novel sequence-type ST3551 (n = 7) were identified. Phylogenetic analysis showed that ST3551 belonged to the cluster of clonal group CG147, and the remaining six STs to the another cluster consisting of four subgroups. The emergence of K. pneumoniae genetic lines carrying epidemiologically significant beta-lactamase genes ST395NDM-1, ST13OXA-48, ST3346OXA-48/CTX-M-14, ST3551OXA-48, and ST39CTX-M-14 was the first case of detection in Russia. Conclusion: The emergence of novel carbapenemase-producing K. pneumoniae genetic lines in Russia highlights the global negative tendency of multidrug-resistant pathogens spread in high-technological medical centers.
Bacteriology
Antimicrobial resistance is a global public health problem. In recent years, increasing of multi-... more Antimicrobial resistance is a global public health problem. In recent years, increasing of multi-drug resistant bacteria has been noted, which are resistant to different antimicrobial groups simultaneously, including beta-lactams. The main mechanism of anti-beta-lactam resistance in gram-negative bacteria is synthesis of various beta-lactamases that hydrolyze the antibiotics. The review is devoted to the analysis of data on the expression of beta-lactamase genes by multi-drug resistant bacteria and molecular genetic methods for their determination in RNA transcripts. Key words: antibiotic resistance, transcriptome, molecular genetic methods, beta-lactamases
Head and Neck Tumors (HNT)
Introduction. Interactions between the 2 microbiota components – bacteria and fungi – are of inte... more Introduction. Interactions between the 2 microbiota components – bacteria and fungi – are of interest as diagnostic and prognostic markers in selection of treatment tactics for oncological patients.Aim. To study microbiota of the oral cavity in patients with primary squamous cell carcinoma of the oropharyngeal area before and after surgical intervention to find biomarkers for rational selection of antifungal drugs.Materials and methods. At the Surgical Department of Head and Neck Tumors of the N. N. Blokhin National Research Center of Oncology, three-component study was performed: investigations of spectrum of Candida spp. isolates, Candida spp. strains’ resistance to antifungals, and oral washes in primary patients before and after surgery. mALDI-Tof microflex LT (Biotyper, Bruker Daltonics, germany) was used for strain identification; Sensititre Yeast ONE, YO10 (Trek Diagnostic System, united kingdom) plates were used for determination of minimal inhibiting concentrations of anti ...
Journal of microbiology, epidemiology and immunobiology
Introduction. Listeria monocytogenes is an important human pathogen causing various forms of list... more Introduction. Listeria monocytogenes is an important human pathogen causing various forms of listeriosis, including foodborne infections, meningitis, neonatal sepsis, and abortion. Listeria are common all over the world.The purpose of the study was to conduct microbiological monitoring of L. monocytogenes in water reservoirs near livestock premises in the Vologda district of the Vologda region.Materials and methods. Bacterial cultures were isolated using two methods, titration and filtration, followed by analysis using methods of conventional bacteriology, serotyping, and species identification by instrumental procedures such as whole genome sequencing, and bioinformatic analysis.Results. Three isolates of L. monocytogenes and one isolate of Listeria innocua were isolated from 12 analyzed water samples (wastewater — 6, river water — 4, and storm water — 2 samples). whole genome sequencing of three L. monocytogenes strains attributed them to the evolutionary line II, and to three seq...
Медицинский совет, May 13, 2022
Резюме Введение. При увеличении уровня приобретенной антибиотикорезистентности патогенов усложняе... more Резюме Введение. При увеличении уровня приобретенной антибиотикорезистентности патогенов усложняется и замедляется лечение, особенно при инфекциях, ассоциированных с биопленками. Возрастает потребность в разработке и использовании новых антибактериальных препаратов, обладаю щих специфичной антимикробной активностью. Цель-изучить антимикробное действие и динамику формирования устойчивости к бензидамина гидрохлориду у различных инфекционных возбудителей. Материалы и методы. Для получения биопленок микроорганизмы культивировали в плоскодонных культуральных планшетах. Планктонные клетки получали суспендированием и пересевом единичных колоний суточной культуры в плоскодонные культуральные планшеты. Для определения антимикробной активности исследуемых препаратов готовили двукратные разведения и вносили в лунки планшета с бактериальной культурой. Динамику формирования устойчивости к бензидамина гидрохлориду изучали, пассируя культуры в жидкой питательной среде с возрастаю щими с двукратным шагом концентрациями антисептика. После 2-3 дней инкубации из пробирки с максимальной концентрацией препарата, в которой наблюдался бактериальный рост, бактерии пересевали в новые, с более высокими концентрациями препарата. Результаты. Бензидамина гидрохлорид проявлял высокий уровень активности против бактерий M. catarrhalis и дрожжеподобных грибов C. albicans. Чуть меньшая активность препарата отмечена для бактерий видов S. aureus и E. coli. Бензидамина гидрохлорид обладал высоким уровнем антибактериальной активности против предварительно сформированных биопленок. Анализ динамики формирования устойчивости к бензидамина гидрохлориду у микроорганизмов различных видов показал, что возможность формирования такой устойчивости крайне мала. Процесс адаптации наблюдался лишь у E. coli. Исследованные штаммы видов S. aureus, C. albicans и M. catarrhalis не приобрели устойчивости к тестируемому препарату. Выводы. Бензидамина гидрохлорид может быть эффективно использован против множества инфекционных возбудителей лор-инфекций, так как показаны высокий уровень его антибактериальной активности против предварительно сформированных биопленок, различных видов бактерий и дрожжеподобных грибов и крайне низкий уровень возникновения устойчивости. Ключевые слова: бензидамина гидрохлорид, антимикробная активность, резистентность, планктонные бактерии, биопленки Благодарности. Работа выполнена в рамках отраслевой программы НИР Роспотребнадзора.
Klinicheskaia laboratornaia diagnostika, Apr 15, 2020
The study is devoted to the study of the antimicrobial activity of the antioxidant dioxidin and t... more The study is devoted to the study of the antimicrobial activity of the antioxidant dioxidin and the complex dioxin-containing preparation Nosolin-ultra, nasal drops against planktonic and biofilm cultures of pathogens of ENT infections, the dynamics of the formation of microbial resistance to dioxidine. 11 reference strains and 9 clinical strains of microorganisms were used in the study: Streptococcus spp., Staphylococcus spp., Micrococcus luteus, Haemophilus influenzae, Acinetobacter pittii, Klebsiella pneumoniae, Moraxella catarrhalis, Pseudomonas aeruginosa. The antimicrobial activity of preparations against planktonic cultures was determined by serial dilution in broth and spot method on solid nutrient media, against biofilms by the applicator method. The dynamics of dioxidine resistance formation was studied by passaging cultures in a liquid nutrient medium with increasing concentrations of antiseptic. Based on the study, it was found that Dioxidin showed antimicrobial activity against plankton cells of all strains (MBC=0.08-5 mg/ml), except S. pyogenes SN345 (MBC>5 mg/ml), inhibited the growth of formed biofilms (MBC=0.08-2.5 mg/ml) of all strains except S. pyogenes SN345 (MBC>5 mg/ml). The drug «Nosolin-ultra, nasal drops» was highly active against plankton cells (MBC=0.04-0.63 mg/ml) and biofilms (MBC=0.02-0.31 mg/ml) of gram-negative bacteria, except A. pittii (MBC>2.5 mg/ml), less active against plankton cells (MBC=1.25-2.5 mg/ml) and biofilms (MBC=0.02-0.31 mg/ml) of gram-positive bacteria and C. albicans. One strain (S. aureus) formed a variant resistant to dioxidine at a concentration of 20 mg/ml, which exceeded the concentration of dioxidine in the complex preparation; other strains (P. aeruginosa, K. pneumoniae, C. albicans) did not form such variants. The data obtained indicate that the drug «Nosolin-ultra, nasal drops» can be effectively used against most pathogens of ENT infections. It is worth noting that with prolonged use of the drug for some types of ENT pathogens in the future, a slight decrease in effectiveness may be noted.
Epidemiology and Vaccinal Prevention
Relevance. Corynebacterium spp., being opportunistic microorganisms, play a role in the developme... more Relevance. Corynebacterium spp., being opportunistic microorganisms, play a role in the development of inflammatory diseases of various localization, including HCAI. Possessing multiple resistance to AMP and pathogenic properties, they cause infections that are not controlled by means of vaccine prophylaxis. The aim of the study was to evaluate the prevalence and virulent properties of Corynebacterium spp. strains isolated from patients with inflammatory diseases of the respiratory tract. Materials and methods. Strains of Corynebacterium spp. isolated from the pharynx and nose of patients with inflammatory diseases of the respiratory tract (99 pcs.) and practically healthy individuals (33 pcs.) at 2017–2021 in Rostov-on-Don. The ultrastructure of corynebacteria was studied using a TecnaiG2 Spirit BioTWIN transmission electron microscope (FEI, Czech Republic); cytopathic effect (CPE) on CHO-K1 cell culture; virulence in the larval model of the wax moth Galleria mellonella. Results an...
Microorganisms
Gram-negative bacteria are prevalent pathogens associated with hospital-acquired infections (HAI)... more Gram-negative bacteria are prevalent pathogens associated with hospital-acquired infections (HAI) that are a major challenge for patient safety, especially in intensive care units [...]
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Papers by Nadezhda Fursova