Alexey V. Feofanov

Education

PeriodCountry, cityEducation institutionAdditional info
Russia, Moscow Moscow Engineering Physics Institute
Russia, Moscow M.V. Lomonosov Moscow State University (biological faculty) PhD in biology
2005 Russia, Moscow M.V. Lomonosov Moscow State University (biological faculty) DSc in biology

Selected publications

  1. Феофанов А.В. (2007). Спектральная лазерная сканирующая конфокальная микроскопия в биологических исследованиях. Успехи биолог. хим. 47, 371–410
  2. Kozlov S.A., Vassilevski A.A., Feofanov A.V., Surovoy A.Y., Karpunin D.V., Grishin E.V. (2006). Latarcins, antimicrobial and cytolytic peptides from the venom of the spider Lachesana tarabaevi (Zodariidae) that exemplify biomolecular diversity. J. Biol. Chem. 281 (30), 20983–92 [+]

    A family of short linear polypeptide molecules, latarcins, was found in the venom of the spider Lachesana tarabaevi. Some peptides were chemically synthesized and their antimicrobial properties were studied. The bactericidal activity of latarcins matched that of the most active known antimicrobial peptides from different animals. The high therapeutic potential of these structurally simple polypeptide molecules will be brought to clinic in the near future.

  3. Sharonov G.V., Karmakova T.A., Kassies R., Pljutinskaya A.D., Grin M.A., Refregiers M., Yakubovskaya R.I., Mironov A.F., Maurizot J.C., Vigny P., Otto C., Feofanov A.V. (2006). Cycloimide bacteriochlorin p derivatives: photodynamic properties and cellular and tissue distribution. Free Radic. Biol. Med. 40 (3), 407–19 [+]

    Reactive oxygen species generated by photosensitizers are efficacious remedy for tumor eradication. Eleven cycloimide derivatives of bacteriochlorin p (CIBCs) with different N-substituents at the fused imide ring and various substituents replacing the 3-acetyl group were evaluated as photosensitizers with special emphasis on structure-activity relationships. The studied CIBCs absorb light within a tissue transparency window (780-830 nm) and possess high photostability at prolonged light irradiation. The most active derivatives are 300-fold more phototoxic toward HeLa and A549 cells than the clinically used photosensitizer Photogem due to the substituents that improve intracellular accumulation (distribution ratio of 8-13) and provide efficient photoinduced singlet oxygen generation (quantum yields of 0.54-0.57). The substituents predefine selective CIBC targeting to lipid droplets, Golgi apparatus, and lysosomes or provide mixed lipid droplets and Golgi apparatus localization in cancer cells. Lipid droplets and Golgi apparatus are critically sensitive to photoinduced damage. The average lethal dose of CIBC-generated singlet oxygen per volume unit of cell was estimated to be 0.22 mM. Confocal fluorescence analysis of tissue sections of tumor-bearing mice revealed the features of tissue distribution of selected CIBCs and, in particular, their ability to accumulate in tumor nodules and surrounding connective tissues. Considering the short-range action of singlet oxygen, these properties of CIBCs are prerequisite to efficient antitumor photodynamic therapy.

  4. Feofanov A.V., Sharonov G.V., Astapova M.V., Rodionov D.I., Utkin Y.N., Arseniev A.S. (2005). Cancer cell injury by cytotoxins from cobra venom is mediated through lysosomal damage. Biochem. J. 390 (Pt 1), 11–8 [+]

    Cytotoxins from cobra venom are known to manifest cytotoxicity in various cell types. It is widely accepted that the plasma membrane is a target of cytotoxins, but the mechanism of their action remains obscure. Using the confocal spectral imaging technique, we show for the first time that cytotoxins from cobra venom penetrate readily into living cancer cells and accumulate markedly in lysosomes. Cytotoxins CT1 and CT2 from Naja oxiana, CT3 from Naja kaouthia and CT1 from Naja haje are demonstrated to possess this property with respect to human lung adenocarcinoma A549 and promyelocytic leukaemia HL60 cells. Immobilized plasma membrane binding accompanies the internalization of CT3 from Naja kaouthia in the HL60 cells, but it is very weak for other cytotoxins. Detectable membrane binding is not a property of any of the cytotoxins tested in A549 cells. The kinetics and concentration-dependence of cytotoxin accumulation in lysosomes correlate well with their cytotoxic effects. On the basis of the results obtained, we propose that lysosomes are a primary target of the lytic action of cytotoxins. Plasma membrane permeabilization seems to be a downstream event relative to lysosome rupture. Direct damage to the plasma membrane may be a complementary mechanism, but its relative contribution to the cytotoxic action depends on the cytotoxin structure and cell type.

  5. Sharonov G.V., Feofanov A.V., Bocharova O.V., Astapova M.V., Dedukhova V.I., Chernyak B.V., Dolgikh D.A., Arseniev A.S., Skulachev V.P., Kirpichnikov M.P. (2005). Comparative analysis of proapoptotic activity of cytochrome c mutants in living cells. Apoptosis 10 (4), 797–808 [+]

    A non-traumatic electroporation procedure was developed to load exogenous cytochrome c into the cytoplasm and to study the apoptotic effect of cytochrome c, its K72-substitued mutants and "yeast --> horse" hybrid cytochrome c in living WEHI-3 cells. The minimum apoptosis-activating intracellular concentration of horse heart cytochrome c was estimated to be 2.7 +/- 0.5 microM (47 +/- 9 fg/cell). The equieffective concentrations of the K72A-, K72E- and K72L-substituted mutants of cytochrome c were five-, 15- and 70-fold higher. The "yeast --> horse" hybrid created by introducing S2D, K4E, A7K, T8K, and K11V substitutions (horse protein numbering) and deleting five N-terminal residues in yeast cytochrome c did not evoke apoptotic activity in mammalian cells. The apoptotic function of cytochrome c was abolished by the K72W substitution. The K72W-substituted cytochrome c possesses reduced affinity to the apoptotic protease activating factor-1 (Apaf-1) and forms an inactive complex. This mutant is competent as a respiratory-chain electron carrier and well suited for knock-in studies of cytochrome c-mediated apoptosis.

  6. Feofanov A., Sharonov G., Grichine A., Karmakova T., Pljutinskaya A., Lebedeva V., Ruziyev R., Yakubovskaya R., Mironov A., Refregier M., Maurizot J.C., Vigny P. (2004). Comparative study of photodynamic properties of 13,15-N-cycloimide derivatives of chlorin p6. Photochem. Photobiol. 79 (2), 172–88 [+]

    Comparative study of 13,15-[N-(2-hydroxyethyl)]cycloimide chlorin p6 (2), 13,15-(N-acetoxy)cycloimide chlorin p6 (3), 13,15-(N-hydroxy)cycloimide chlorin p6 methyl ester (4) and 13,15-(N-methoxy)cycloimide chlorin p6 methyl ester (5) together with the previously investigated 13,15-[N-(3-hydroxypropyl)]cycloimide chlorin p6 (1) was performed. The dependence of the key photodynamic properties of 1-5 on the introduced substituents was analyzed. The photoinduced cell-killing activity of 4 is 100- and 280-fold higher than that of chlorin p6 and Photogem, respectively, as estimated on A549 human lung adenocarcinoma cells. The activity is reduced eight times in the order 4 > 5 > 1 > 2 > 3. The intracellular accumulation of 1-5 occurs in cytoplasm in a monomeric form bound to the lipids of cellular membranes. This form of 1, 2, 3, 4 and 5 is characterized by the high quantum yield of singlet oxygen generation, which depends on the introduced substituents, 0.66, 0.59, 0.35, 0.51 and 0.73, respectively. The photostability is two-fold less for 1 and four-fold less for 2, 3 and 5 than for 4. The rates of cellular uptake and efflux of 1-5 vary widely, thus providing the way to optimize the pharmacological properties of the photosensitizer (PS) using the respective substituents. Modifying the substituents, 1-5 were targeted to different cellular organelles. The enhanced accumulation in the Golgi apparatus and mitochondria complemented with diffuse staining of intracellular membranous structures is a property of 1-4. Compound 5 accumulates selectively in the lipid droplets and stains weakly perinuclear structures. Temperature-sensitive mechanisms of transport are responsible for the 1-4 uptake. Diffusion can play a role in the internalization of 5 but not of 1-4. Endocytosis via caveolae, clathrin-dependent and adenosine triphosphate-dependent pathways are not noticeably involved in the 1-5 internalization. Independently from their intracellular localization 1, 4 and 5 are highly efficient near-IR PS, which induce predominantly an apoptotic type of cell death under conditions providing ca 50% level of phototoxicity and necrosis at the 100% level of phototoxicity.

  7. Chudakov D.M., Feofanov A.V., Mudrik N.N., Lukyanov S., Lukyanov K.A. (2003). Chromophore environment provides clue to "kindling fluorescent protein" riddle. J. Biol. Chem. 278 (9), 7215–9 [+]

    asCP, the unique green fluorescent protein-like nonfluorescent chromoprotein from the sea anemone Anemonia sulcata, becomes fluorescent ("kindles") upon green light irradiation, with maximum emission at 595 nm. The kindled protein then relaxes to a nonfluorescent state or can be "quenched" instantly by blue light irradiation. In this work, we used asCP mutants to investigate the mechanism underlying kindling. Using site-directed mutagenesis we showed that amino acids spatially surrounding Tyr(66) in the chromophore are crucial for kindling. We propose a model of the kindling mechanism, in which the key event is chromophore turning or cis-trans isomerization. Using site-directed mutagenesis we also managed to transfer the kindling property to the two other coral chromoproteins. Remarkably, most kindling mutants were capable of both reversible and irreversible kindling. Also, we obtained novel variants that kindled upon blue light irradiation. The diversity of photoactivated fluorescent proteins that can be developed by site-directed mutagenesis is promising for biotechnological needs.