Publications by authors named "Lepekhina E"

Isogenic knockout mutants of Escherichia coli deficient in components of the glutathione and thioredoxin redox systems and growing at various temperatures (20-46°C) exhibited considerable differences in growth rate and survival, as well as in expression of the antioxidant genes. In the parent strain E. coli BW25113 (wt) treated with ciprofloxacin, ampicillin, or streptomycin, dependence of survival from growth temperature was a V-shaped curve with the maximum sensitivity within the range corresponding to high growth rates (40-44°C).

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Recently, it was proposed that some antibiotics stimulate the production of reactive oxygen species (ROS), which contribute to cell death. Later, other research groups have provided arguments against ROS-mediated killing of bacteria by antibiotics. At present, there remain a number of unanswered questions in understanding of the role of ROS in killing by antibiotics.

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The emission of conjugated polymer nanoparticles (CPNs or Pdots) is often tailored for specific uses by functionalizing CPNs with dyes that act as fluorescence resonance energy transfer (FRET) acceptors. A number of dye functionalization methods for CPNs have been developed, ranging from simple noncovalent doping to covalent attachment. We seek to develop guidelines for when noncovalent doping is acceptable and when covalent attachment is necessary to achieve the desired result.

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Low concentrations of black tea and water extracts from medicinal plants Arctostaphylos uva-ursi, Vaccinium vitis-idaea, Tilia cordata, Betula pendula and Zea mays stimulated biofilm formation in Escherichia coli BW25113 up to three times. Similar effect was observed for tannic acid and low concentrations of quercetin. In contrast, the extract from Urtica dioica reduced biofilm production.

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A series of metal-organic networks of CuSCN were prepared by direct reactions with substituted pyridine and aliphatic amine ligands, L. Thiocyanate bridging is seen in all but 1 of 11 new X-ray structures. Structures are reported for (CuSCN)L sheets (L = 3-chloro- and 3-bromopyridine, N-methylmorpholine), ladders (L = 2-ethylpyridine, N-methylpiperidine), and chains (L = 2,4,6-collidine).

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