Некрасова Оксана Васильевна


Период обученияСтрана, городУчебное заведениеДополнительная информация
1972–1977 Россия, Москва МГУ имени М.В.Ломоносова, биологический факультет

Избранные публикации

  1. Nekrasova O., Yakimov S., Kirpichnikov M., Feofanov A. (2017). Recombinant scorpion toxins: Focus on four-disulfide peptide blockers of Kv1-channels. Bioengineered , 1–5 [+]

    We have recently developed a simple and effective bioengineering approach to large-scale production of alpha-KTx, peptide toxins from scorpion venoms, that block voltage-gated potassium channels with high affinity and specificity. This approach was successfully approved for different peptides containing three disulfide bonds. To extend this method to production of peptide toxins with four disulfide bridges, in particular, maurotoxin and hetlaxin, appropriate conditions of a cleavage reaction with tobacco etch virus (TEV) protease need to be found. For this, the interplay between efficiency of TEV hydrolysis and sensitivity of the target peptides to disulfide reducing agents was studied, and optimized protocols of TEV cleavage reaction were worked out. Maurotoxin and hetlaxin were produced in a folded form avoiding in vitro renaturation step with yields of 14 and 12 mg/liter of culture, respectively.

  2. Smitienko O.A., Nekrasova O.V., Kudriavtsev A.V., Yakovleva M.A., Shelaev I.V., Gostev F.E., Dolgikh D.A., Kolchugina I.B., Nadtochenko V.A., Kirpichnikov M.P., Feldman T.B., Ostrovsky M.A. (2017). Femtosecond and Picosecond Dynamics of Recombinant Bacteriorhodopsin Primary Reactions Compared to the Native Protein in Trimeric and Monomeric Forms. Biochemistry Mosc. 82 (4), 490–500 [+]

    Исследована динамика первичных реакций рекомбинантного бактериородопсина (светочувствительного белка из Halobacterium salinarum) методом фемтосекундной лазерной абсорбционной спектроскопии. Показано, что фотохимические свойства рекомбинантногго бактериородопсина в большой степени соответствуют свойствам природного белка в мономерной форме. Таким образом, полученный рекомбинантный белок является удобной моделью для изучения фотохимической активности бактериородопсина. 

  3. Nekrasova O., Kudryashova K., Fradkov A., Yakimov S., Savelieva M., Kirpichnikov M., Feofanov A. (2016). Straightforward approach to produce recombinant scorpion toxins-Pore blockers of potassium channels. J. Biotechnol. 241, 127–135 [+]

    Scorpion venom peptide blockers (KTx) of potassium channels are a valuable tool for structure-functional studies and prospective candidates for medical applications. Low yields of recombinant KTx hamper their wide application. We developed convenient and efficient bioengineering approach to a large-scale KTx production that meets increasing demands for such peptides. Maltose-binding protein was used as a carrier for cytoplasmic expression of folded disulfide-rich KTx in E. coli. TEV protease was applied for in vitro cleavage of the target peptide from the carrier. To produce KTx with retained native N-terminal sequence, the last residue of TEV protease cleavage site (CSTEV) was occupied by the native N-terminal residue of a target peptide. It was shown that decreased efficiency of hydrolysis of fusion proteins with non-canonical CSTEV can be overcome without by-product formation. Disulfide formation and folding of a target peptide occurred in cytoplasm eliminating the need for renaturation procedure in vitro. Advantages of this approach were demonstrated by producing six peptides with three disulfide bonds related to four KTx sub-families and achieving peptide yields of 12-22mg per liter of culture. The developed approach can be of general use for low-cost production of various KTx, as well as other disulfide-rich peptides and proteins.

  4. Feldman T.B., Smitienko O.A., Shelaev I.V., Gostev F.E., Nekrasova O.V., Dolgikh D.A., Nadtochenko V.A., Kirpichnikov M.P., Ostrovsky M.A. (2016). Femtosecond spectroscopic study of photochromic reactions of bacteriorhodopsin and visual rhodopsin. J. Photochem. Photobiol. B, Biol. 164, 296–305 [+]

    Photochromic ultrafast reactions of bacteriorhodopsin (H. salinarum) and bovine rhodopsin were conducted with a femtosecond two-pump probe pulse setup with the time resolution of 20-25fs. The dynamics of the forward and reverse photochemical reactions for both retinal-containing proteins was compared. It is demonstrated that when retinal-containing proteins are excited by femtosecond pulses, dynamics pattern of the vibrational coherent wave packets in the course of the reaction is different for bacteriorhodopsin and visual rhodopsin. As shown in these studies, the low-frequencies that form a wave packets experimentally observed in the dynamics of primary products formation as a result of retinal photoisomerization have different intensities and are clearer for bovine rhodopsin. Photo-reversible reactions for both retinal proteins were performed from the stage of the relatively stable photointermediates that appear within 3-5ps after the light pulse impact. It is demonstrated that the efficiency of the reverse phototransition K-form→bacteriorhodopsin is almost five-fold higher than that of the Batho-intermediate→visual rhodopsin phototransition. The results obtained indicate that in the course of evolution the intramolecular mechanism of the chromophore-protein interaction in visual rhodopsin becomes more perfect and specific. The decrease in the probability of the reverse chromophore photoisomerization (all-trans→11-cis retinal) in primary photo-induced rhodopsin products causes an increase in the efficiency of the photoreception process.

  5. Nekrasova O.V., Volyntseva A.D., Kudryashova K.S., Novoseletsky V.N., Lyapina E.A., Illarionova A.V., Yakimov S.A., Korolkova Y.V., Shaitan K.V., Kirpichnikov M.P., Feofanov A.V. (2016). Complexes of Peptide Blockers with Kv1.6 Pore Domain: Molecular Modeling and Studies with KcsA-Kv1.6 Channel. J Neuroimmune Pharmacol , [+]

    Разработан комплексный подход к поиску, исследованию и конструированию  пептидных блокаторов калиевого канала Kv1.6. Подход основан на применении разработанной нами биоинженерной аналитической системы для изучения связывания блокаторов с гибридным каналом KcsA-Kv1.6 методом конфокальной микроскопии и молекулярного моделирования комплексов пептидных блокаторов с каналом Kv1.6. Используя разработанный подход, охарактеризована аффинность ряда пептидных блокаторов к каналу Kv1.6, построены молекулярные модели их комплексов, описан интерфейс взаимодействия и аминокислотные остатки, влияющие на селективность  взаимодействия блокаторов с каналом Kv1.6.

  6. Kuzmenkov A.I., Nekrasova O.V., Kudryashova K.S., Peigneur S., Tytgat J., Stepanov A.V., Kirpichnikov M.P., Grishin E.V., Feofanov A.V., Vassilevski A.A. (2016). Fluorescent protein-scorpion toxin chimera is a convenient molecular tool for studies of potassium channels. Sci Rep 6, 33314 [+]

    Ion channels play a central role in a host of physiological and pathological processes and are the second largest target for existing drugs. There is an increasing need for reliable tools to detect and visualize particular ion channels, but existing solutions suffer from a number of limitations such as high price, poor specificity, and complicated protocols. As an alternative, we produced recombinant chimeric constructs (FP-Tx) consisting of fluorescent proteins (FP) fused with potassium channel toxins from scorpion venom (Tx). In particular, we used two FP, eGFP and TagRFP, and two Tx, OSK1 and AgTx2, to create eGFP-OSK1 and RFP-AgTx2. We show that these chimeras largely retain the high affinity of natural toxins and display selectivity to particular ion channel subtypes. FP-Tx are displaced by other potassium channel blockers and can be used as an imaging tool in ion channel ligand screening setups. We believe FP-Tx chimeras represent a new efficient molecular tool for neurobiology.

  7. Dolgikh D.A., Malyshev A.Y., Salozhin S.V., Nekrasova O.V., Petrovskaya L.E., Roshchin M.V., Borodinova A.A., Feldman T.B., Balaban P.M., Kirpichnikov M.P., Ostrovsky M.A. (2015). Anion-selective channelrhodopsin expressed in neuronal cell culture and in vivo in murine brain: Light-induced inhibition of generation of action potentials. Dokl. Biochem. Biophys. 465 (1), 424–7 [+]

    Anionic channelrhodopsin slow ChloC was expressed in the culture of nerve cells and in vivo in mouse brain. We demonstrated ability of slow ChloC to suppress effectively the activity of the neuron in response to the illumination with the visible light. It has been shown for a first time that slow ChloC works equally efficiently in both neuronal culture and in the whole brain being expressed in vivo. Thus, slow ChloC could be considered as an effective optogenetic tool capable in response to light stimulation to inhibit the generation of action potentials in the neuron.

  8. Kuzmenkov A.I., Vassilevski A.A., Kudryashova K.S., Nekrasova O.V., Peigneur S., Tytgat J., Feofanov A.V., Kirpichnikov M.P., Grishin E.V. (2015). Variability of Potassium Channel Blockers in Mesobuthus eupeus Scorpion Venom with Focus on Kv1.1: AN INTEGRATED TRANSCRIPTOMIC AND PROTEOMIC STUDY. J. Biol. Chem. 290 (19), 12195–209 [+]

    The lesser Asian scorpion Mesobuthus eupeus (Buthidae) is one of the most widely spread and dispersed species of the Mesobuthus genus, and its venom is actively studied. Nevertheless, a considerable amount of active compounds is still under-investigated due to the high complexity of this venom. Here, we report a comprehensive analysis of putative potassium channel toxins (KTxs) from the cDNA library of M. eupeus venom glands, and we compare the deduced KTx structures with peptides purified from the venom. For the transcriptome analysis, we used conventional tools as well as a search for structural motifs characteristic of scorpion venom components in the form of regular expressions. We found 59 candidate KTxs distributed in 30 subfamilies and presenting the cysteine-stabilized α/β and inhibitor cystine knot types of fold. M. eupeus venom was then separated to individual components by multistage chromatography. A facile fluorescent system based on the expression of the KcsA-Kv1.1 hybrid channels in Escherichia coli and utilization of a labeled scorpion toxin was elaborated and applied to follow Kv1.1 pore binding activity during venom separation. As a result, eight high affinity Kv1.1 channel blockers were identified, including five novel peptides, which extend the panel of potential pharmacologically important Kv1 ligands. Activity of the new peptides against rat Kv1.1 channel was confirmed (IC50 in the range of 1-780 nm) by the two-electrode voltage clamp technique using a standard Xenopus oocyte system. Our integrated approach is of general utility and efficiency to mine natural venoms for KTxs.

  9. Hoang A.N., Vo H.D., Vo N.P., Kudryashova K.S., Nekrasova O.V., Feofanov A.V., Kirpichnikov M.P., Andreeva T.V., Serebryakova M.V., Tsetlin V.I., Utkin Y.N. (2014). Vietnamese Heterometrus laoticus scorpion venom: evidence for analgesic and anti-inflammatory activity and isolation of new polypeptide toxin acting on Kv1.3 potassium channel. Toxicon 77, 40–8 [+]

    The scorpion Heterometrus laoticus (Scorpionidae) inhabits Indochinese peninsula and is widely distributed in South-West Vietnam. Since no human fatalities caused by H. laoticus stings were reported, no systematic characterization of the venom was earlier done. In this study we report on biological activity of the venom from H. laoticus caught in Vietnamese province An Giang. The venom manifested a very low acute toxicity with LD50 of about 190 mg/kg body weight in mice at subcutaneous (s.c.) injection and 12 mg/kg at intravenous injection. The venom analgesic effects using tail immersion and writhing tests as well as anti-inflammatory effect using carrageenan test were analyzed at doses of 9.5 and 19 mg/kg at s.c. injections. It was found that at two doses tested H. laoticus venom showed both anti-nociceptive and anti-inflammatory activity. The venom was fractionated by means of gel-filtration and reversed-phase HPLC. As a result several polypeptide toxins were isolated and new toxin hetlaxin was identified. Its amino acid sequence was determined and binding to the extracellular vestibule of the K⁺-conducting pore of Kv1.1 and Kv1.3 potassium channels was studied. Hetlaxin belongs to the scorpion alpha-toxin family and is the first toxin isolated from H. laoticus venom which possesses high affinity (K(i) 59 nM) to Kv1.3 potassium channel.

  10. Shenkarev Z.O., Lyukmanova E.N., Butenko I.O., Petrovskaya L.E., Paramonov A.S., Shulepko M.A., Nekrasova O.V., Kirpichnikov M.P., Arseniev A.S. (2013). Lipid-protein nanodiscs promote in vitro folding of transmembrane domains of multi-helical and multimeric membrane proteins. Biochim. Biophys. Acta 1828 (2), 776–84 [+]

    Production of helical integral membrane proteins (IMPs) in a folded state is a necessary prerequisite for their functional and structural studies. In many cases large-scale expression of IMPs in cell-based and cell-free systems results in misfolded proteins, which should be refolded in vitro. Here using examples of the bacteriorhodopsin ESR from Exiguobacterium sibiricum and full-length homotetrameric K(+) channel KcsA from Streptomyces lividans we found that the efficient in vitro folding of the transmembrane domains of the polytopic and multimeric IMPs could be achieved during the protein encapsulation into the reconstructed high-density lipoprotein particles, also known as lipid-protein nanodiscs. In this case the self-assembly of the IMP/nanodisc complexes from a mixture containing apolipoprotein, lipids and the partially denatured protein solubilized in a harsh detergent induces the folding of the transmembrane domains. The obtained folding yields showed significant dependence on the properties of lipids used for nanodisc formation. The largest recovery of the spectroscopically active ESR (~60%) from the sodium dodecyl sulfate (SDS) was achieved in the nanodiscs containing anionic saturated lipid 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPG) and was approximately twice lower in the zwitterionic DMPC lipid. The reassembly of tetrameric KcsA from the acid-dissociated monomer solubilized in SDS was the most efficient (~80%) in the nanodiscs containing zwitterionic unsaturated lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC). The charged and saturated lipids provided lower tetramer quantities, and the lowest yield (<20%) was observed in DMPC. The overall yield of the ESR and KcsA folding was mainly restricted by the efficiency of the protein encapsulation into the nanodiscs.

  11. Kudryashova K.S., Nekrasova O.V., Kuzmenkov A.I., Vassilevski A.A., Ignatova A.A., Korolkova Y.V., Grishin E.V., Kirpichnikov M.P., Feofanov A.V. (2013). Fluorescent system based on bacterial expression of hybrid KcsA channels designed for Kv1.3 ligand screening and study. Analytical and bioanalytical chemistry , [+]

    Human voltage-gated potassium channel Kv1.3 is an important pharmacological target for the treatment of autoimmune and metabolic diseases. Increasing clinical demands stipulate an active search for efficient and selective Kv1.3 blockers. Here we present a new, reliable, and easy-to-use analytical system designed to seek for and study Kv1.3 ligands that bind to the extracellular vestibule of the K(+)-conducting pore. It is based on Escherichia coli spheroplasts with the hybrid protein KcsA-Kv1.3 embedded into the membrane, fluorescently labeled Kv1.3 blocker agitoxin-2, and confocal laser scanning microscopy as a detection method. This system is a powerful alternative to radioligand and patch-clamp techniques. It enables one to search for Kv1.3 ligands both among individual compounds and in complex mixtures, as well as to characterize their affinity to Kv1.3 channel using the "mix and read" mode. To demonstrate the potential of the system, we performed characterization of several known Kv1.3 ligands, tested nine spider venoms for the presence of Kv1.3 ligands, and conducted guided purification of a channel blocker from scorpion venom.

  12. Nekrasova O.V., Sharonov G.V., Tikhonov R.V., Kolosov P.M., Astapova M.V., Yakimov S.A., Tagvey A.I., Korchagina A.A., Bocharova O.V., Wulfson A.N., Feofanov A.V., Kirpichnikov M.P. (2012). Receptor-binding domain of ephrin-A1: production in bacterial expression system and activity. Biochemistry Mosc. 77 (12), 1387–94 [+]

    Eph receptor tyrosine kinases and their ligands, the ephrins, perform an important regulatory function in tissue organization, as well as participate in malignant transformation of cells. Ephrin-A1, a ligand of A class Eph receptors, is a modulator of tumor growth and progression, and the mechanism of its action needs detailed investigation. Here we report on the development of a system for bacterial expression of an ephrin-A1 receptor-binding domain (eA1), a procedure for its purification, and its renaturation with final yield of 50 mg/liter of culture. Functional activity of eA1 was confirmed by immunoblotting, laser scanning confocal microscopy, and flow cytometry. It is shown that monomeric non-glycosylated receptor-binding domain of ephrin-A1 is able to activate cellular EphA2 receptors, stimulating their phosphorylation. Ligand eA1 can be used to study the features of ephrin-A1 interactions with different A class Eph receptors. The created expression cassette is suitable for the development of ligands with increased activity and selectivity and experimental systems for the delivery of cytotoxins into tumor cells that overexpress EphA2 or other class A Eph receptors.

  13. Nekrasova O.V., Wulfson A.N., Tikhonov R.V., Yakimov S.A., Simonova T.N., Tagvey A.I., Dolgikh D.A., Ostrovsky M.A., Kirpichnikov M.P. (2010). A new hybrid protein for production of recombinant bacteriorhodopsin in Escherichia coli. J. Biotechnol. 147 (3-4), 145–50 [+]
  14. Shenkarev Z.O., Lyukmanova E.N., Solozhenkin O.I., Gagnidze I.E., Nekrasova O.V., Chupin V.V., Tagaev A.A., Yakimenko Z.A., Ovchinnikova T.V., Kirpichnikov M.P., Arseniev A.S. (2009). Lipid-protein nanodiscs: possible application in high-resolution NMR investigations of membrane proteins and membrane-active peptides. Biochemistry Mosc. 74 (7), 756–65 [+]

    High-resolution NMR is shown to be applicable for investigation of membrane proteins and membrane-active peptides embedded into lipid-protein nanodiscs (LPNs). (15)N-Labeled K+-channel from Streptomyces lividans (KcsA) and the antibiotic antiamoebin I from Emericellopsis minima (Aam-I) were embedded in LPNs of different lipid composition. Formation of stable complexes undergoing isotropic motion in solution was confirmed by size-exclusion chromatography and (31)P-NMR spectroscopy. The 2D 1H-(15)N-correlation spectra were recorded for KcsA in the complex with LPN containing DMPC and for Aam-I in LPNs based on DOPG, DLPC, DMPC, and POPC. The spectra recorded were compared with those in detergent-containing micelles and small bicelles commonly used in high-resolution NMR spectroscopy of membrane proteins. The spectra recorded in LPN environments demonstrated similar signal dispersion but significantly increased (1)H(N) line width. The spectra of Aam-I embedded in LPNs containing phosphatidylcholine showed significant selective line broadening, thus suggesting exchange process(es) between several membrane-bound states of the peptide. (15)N relaxation rates were measured to obtain the effective rotational correlation time of the Aam-I molecule. The obtained value (approximately 40 nsec at 45 degrees C) is indicative of additional peptide motions within the Aam-I/LPN complex.

  15. Nekrasova O.V., Ignatova A.A., Nazarova A.I., Feofanov A.V., Korolkova Y.V., Boldyreva E.F., Tagvei A.I., Grishin E.V., Arseniev A.S., Kirpichnikov M.P. (2009). Recombinant Kv channels at the membrane of Escherichia coli bind specifically agitoxin2. J Neuroimmune Pharmacol 4 (1), 83–91 [+]

    Potassium voltage-gated channels (Kv) are considered as molecular targets in a number of serious neuronal, immune, and cardiac disorders. Search for efficient low-molecular weight modulators of Kv channel function provides a basis for the development of an appropriate therapy for various Kv-mediated diseases. We report here on a new bacterial cell-based system, which is suitable for study of interactions between ligands and ligand-binding sites of eukaryotic Kv1.3 and Kv1.1 channels. To create this system, high-level expression of KcsA-Kv1.3 and KcsA-Kv1.1 hybrid proteins (ligand-binding sites of Kv1.3 or Kv1.1 fused with prokaryotic KcsA potassium channel) was achieved in the plasma membrane of Escherichia coli. An efficient procedure of E. coli conversion to intact spheroplasts was developed. We demonstrate that fluorescently labeled agitoxin 2 binds specifically to high-affinity and lower-affinity sites of KcsA-Kv1.3 and KcsA-Kv1.1, respectively, at the membrane of spheroplasts. Number of binding sites per cell is estimated to be (1.0 +/- 0.6) x 10(5) and (0.3 +/- 0.2) x 10(5) for KcsA-Kv1.3- and KcsA-Kv1.1-presenting cells, respectively, that allows reliable detection of ligand-receptor interactions by confocal laser scanning microscopy. This bacterial cell-based system is intended for screening of ligands to membrane-embedded pharmaceutical targets.