Tag Archives: Escherichia coli
Influence of lipopolysaccharides of Escherichia coli on the protease activity of several Bacillus strains
L. D. Varbanets1, O. S. Brovarska1, O. V. Gudzenko1*,
K. G. Garkava2, A. R. Makarenko2
1Institute of Microbiology and Virology named after D. K. Zabolotny,
National Academy of Sciences of Ukraine, Kyiv, Ukraine;
2National Technical University of Ukraine
“Igor Sykorsky Kyiv Polytechnic Institute”, Kyiv, Ukraine;
*e-mail: alena.gudzenko81@gmail.com
Received: 07 July 2025; Revised: 23 August 2025;
Accepted: 12 September 2025; Available on-line: 17 September 2025
We have previously shown that lipopolysaccharides (LPS) of a number of strains of the phytopathogenic species Pantoea agglomerans are capable of increasing the activity of Bacillus peptidases with fibrinolytic, elastase and collagenase activities by 2-4 times. The aim of this work was to investigate the effect of isolated intracellular LPS1 and extracellular LPS2 of Escherichia coli on the activity of purified bacilli proteases with elastase and fibrinogenolytic activity. It was shown that both LPS2 and LPS1 of E. coli 23 can increase the elastase activity of Bacillus sp. IMV B-7883 by 600 and 416% respectively. Both LPS are able to increase fibrinogenolytic activity in all studied Bacillus strains, but its greatest stimulation (200%) was observed under the action of LPS2 of Bacillus sp. L9.
Undecylenic acid and N,N-dibutylundecenamide as effective antibacterials against antibiotic-resistant strains
Y. D. Startseva*, D. M. Hodyna, I. V. Semenyuta,
O. P. Tarasyuk, S. P. Rogalsky, L. O. Metelytsia
V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry,
National Academy of Sciences of Ukraine, Kyiv;
*e-mail: startseva1991@gmail.com
Received: 25 April 2023; Revised: 03 July 2023;
Accepted: 7 September 2023; Available on-line: 12 September 2023
Evaluation of undecylenic acid (UA) and its tertiary amide N,N-dibutylundecenamide (DBUA) activity in vitro against the standard and antibiotic-resistant Escherichia coli and Staphylococcus aureus strains was carried out. The antibacterial potential of the acid and its amide at 2.5 and 5.0 μM concentration both against gram-positive bacteria (S. aureus) and gram-negative (E. coli) cultures was confirmed by monitoring the diameter of the bacterial growth inhibition zones. The docking study identified methionine aminopeptidase (MAP) as the most energy-favorable potential biotarget associated with the drug resistance of E. coli and S. aureus with a binding energy in the range from -8.0 to -8.5 kcal/mol. The ligands complexation was due to the formation of hydrogen bonds with ASP108, HIS171, HIS178, GLU204, GLU235, HIS76, ASP104, GLU233, ASP93 and metal-acceptor interactions with Co2+. Overall, the results indicated that UA and DBUA activity against antibiotic-resistant strains creates prospects for the development of new antibacterial formulations.
The effect of chlorination of nucleotide bases on the conformational properties of thymidine monophosphate
T. M. Mukhina, T. Yu. Nikolaienko
Taras Shevchenko National University of Kyiv, Ukraine;
e-mail: MukhinaTanyaM@gmail.com; tim_mail@ukr.net
Recent studies on Escherichia coli bacteria cultivation, in which DNA thymine was replaced with 5-chlorouracil have refreshed the problem of understanding the changes to physical properties of DNA monomers resultant from chemical modifications. These studies have shown that the replacement did not affect the normal activities and division of the bacteria, but has significantly reduced its life span. In this paper a comparative analysis was carried out by the methods of computational experiment of a set of 687 possible conformers of natural monomeric DNA unit (2′-deoxyribonucleotide thymidine monophosphate) and 660 conformers of 5-chloro-2′-deoxyuridine monophosphate – a similar molecules in which the natural nitrogenous base thymine is substituted with 5-chlorouracil. Structures of stable conformers of the modified deoxyribonucleotide have been obtained and physical factors, which determine their variation from the conformers of the unmodified molecule have been analyzed. A comparative analysis of the elastic properties of conformers of investigated molecules and non-covalent interactions present in them was conducted. The results can be used for planning experiments on synthesis of artificial DNA suitable for incorporation into living organisms.