Home LABORATORY OF EVOLUTIONARY BIOCHEMISTRY


[Head of Laboratory ] [Area of Interest] [Main  Results] [Research cooperation] [Typical publications]


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Head of Laboratory:
    Since 1998 laboratory is headed by Professor
    Mikhail Sergeyevich KRITSKY,
    Ph.D., D.Sc.
    tel.:  +7(495)-952-3431
    Fax: +7-(495) 9542732
    e-mail:
    mkritsky AT inbi.ras.ru
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    Evolutionary studies, including a modeling of chemical processes leading to prebiotic synthesis of organic molecules, have been conducted in the Institute since the mid-fifties. The research unit entitled as Laboratory of Evolutionary Biochemistry was founded in 1980. Today this laboratory consists of twelve permanent researchers. It also includes a varying non-permanent stuff and pre- and postgraduate students


Area  of Interest:
    The studies of the origin and evolution of metabolism is a priority interest of laboratory.
        Coenzyme photobiochemistry and evolution. This line of research is aimed to a design of the enzyme-free models of metabolic processes involving nucleotide and pteridine coenzymes (flavins and pterins). These ubiquitous cofactors of enzymes are evolutionary ancient molecules and a modeling of their abiotic synthesis and polymerization is an important aspect of the laboratory’s research. The main effort is focused to investigation of photochemical properties of coenzymes. Photoexcitation dramatically enhances catalytic activity of pteridine molecules and photochemical study of these molecules is a prerequisite for a design of prebiotic metabolism models. Besides, results of this study is used to develop new technologies of drug production. The design and photochemical investigation of prebiotic models is supplemented with analysis of function and evolution of modern photoreceptor proteins binding pteridine coenzymes as photosensors. This research is mainly focused on the flavoprotein photoreceptor WCC functioning in cells of fungus Neurospora crassa.
    Fungal cell and stress. The group headed by Professor Tatyana A. Belozerskaya investigates the influence of stressors such as light, starvation and ionizing radiation on the developmental processes in fungi differing in taxonomic position. The goal of this research is to elucidate a mediating role of reactive oxygen species in stress and its significance for growth and differentiation of mycelium as well as the function in fungal cell of the oxidative stress-protective mechanisms.

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Main  Results:
    The laboratory’s activitys is supported by Presidium RAS Basic Research Program ¹ 18 “Problems of Origin and Evolution of the Biosphere” and by grants obtained from Russian Foundation for Basic Research. Below follow main results obtained in laboratory during the last five years.
       Prebiotic models. A novel model for abiogenic formation of organics was developed. To mimick electrochemical processes in hydrothermal vents contacting sulfide minerals this model consisted of electrochemical cell equipped with pyrite cathode and placed into autoclave. A synthesis of formate from CO2 was demonstrated in this model.
    Most prebiotic models developed in laboratory were designed to reproduce enzyme-free synthesis and transformation of nucleotides and coenzymes in geochemically relevant conditions. The 5?-AMP to FMN condensation to FAD was demonstrated in such a model thus illustrating availability of complex coenzyme molecules in prebiotic processes. The UV-irradiation was shown to activate clay mineral surface: 5?-AMP molecules adsorbed on such a pre-activated surface entered polymerization reaction and formed 3?,5?-phosphodiester oligomer products. The effect of UV irradiation resulted from a photolytic formation of hydrogen peroxide in mineral. By using products of amino acids thermolysis consisting of abiogenic flavin pigment and proteinoid polymer spontaneously aggregated to form microspheres, efficient models for ADP photophosphorylation by Pi to form ATP were developed. When excited, these models phosphorylated ADP to ATP with a yield of tens percent. The reaction was mediated by excited flavin and free radical process, i.e. its mechanism was basically different from modern photophosphorylation.
       Coenzyme photochemistry and natural selection. The photochemical investigation of a series of pteridine coenzyme derivatives permitted to outline a complex of molecular properties, which have favored selection of a “dark metabolism” coenzyme 5,10-methenyl-tetrahydrofolate, for a role of light-harvesting antenna in photoreceptor proteins.
       Pteridine photoreceptors in organisms. The activity of flavoprotein WCC photoreceptor in cells of Neurospora crassa was shown to control methylation level of genome thus regulating a choice by the organism of sexual or asexual developmental pathway.
       Fungal cell and stress. It was shown that fungi isolated from the inner locations of the 4th Unit of Chernobyl NPP and 10-km limit zone are one order of magnitude more resistant to oxidative stress than similar species from areas with a background radioactivity. Fungal organisms may use various strategies for antioxidant defense. For instance, in Neurospora crassa there are enzymes detoxifying reactive oxygen species (ROS), first of all, Cu/Zn- and Mn- superoxide dismutases, and catalases that play a main role in this process. A great role in stress resistance of N.crassa plays intracellular redox homeostasis. Accumulation in cells of caroteniod pigments supplements this mechanism additionally protecting organism against photodamage. Another strategy is used in Blakeslea trispora. Enzymes detoxifying ROS are easily degradable in this organism what is compensated by accumulation of antioxidant b-carotene.
       Innovative activity. An economical and environmentally appropriate method for manufacturing of calcium folinate – a medicine for anticancer and antianemic therapy – was devised by laboratory in cooperation with Vitamin Institute. Russian Federation Patent 2241711. Method for producing calcium folinate. Authors: Kritsky MS, Telegina TA, Zemskova YL, Rudakova IP, Nadtochiy MA, Kolesnikov MP.
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Research cooperation:
    –Institute of chemical physics, RAS
    A.N. Belozersky Institute for Physicochemical Biology, Moscow University.
    Institute of Theoretical and Experimental Biophysics RAS, Pushchino.
    Institute of Physics, University of St-Petersburg.
    Vitamin Institute, Moscow.
    Biozentrum Innsbruck Medizinische Universitat, Innsbruck, Austria.
    Dept. of Chemistry and Biochemistry, Concordia University Montreal, Quebeck, Canada.
    D.K. Zabolotny Institute of Microbiology and Virology NA S, Kiev, Ukraine.

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Typical publications:
    Kritsky MS, Russo VEA, Filippovich SY, Afanasieva TP, Bachurina GP (2002) The opposed effect of 5-azacytidine and light on the development of reproductive structures in Neurospora crassa. Photochem Photobiol. 75, 79-83.
    Aslanidi KB, Ivanova AE, Blazheevskaya YV, Zhdanova NN, Belozerskaya TA (2003) Resistance of microscopic fungi to oxidative stress. Dokl Biochem Biophys. 392, 241-243.
    Emelin A.V, Otroshchenko VA, Ryabchuk VK, Serpone N (2003). Abiogenesis and photostimulated heterogeneous reactions in the interstellar medium and on primitive Earth. Relevance to the genesis of life. J Photochem Photobiol C: Revs., 3, 203-224.
    Belozerskaya TA, Potapova TV, Isakova EP, Shurubor EI, Savel'eva LV, Zvyagilskaya RA (2003). Energy status of Neurospora crassa mutant nap in relation to accumulation of carotenoids. J Microbiol 41, 41-45.
    Kritsky MS, Telegina TA (2004). Role of nucleotide-like coenzymes in primitive evolution. In: Origins: Genesis, Evolution and Diversity of Life (J.Seckbach, ed.) Kluwer Academic Publs, Dordrecht, P 215-231.
    Vladimirov MG, Ryzhkov YF, Alekseev VA, Bogdanovskaya VA, Otroshchenko VA., Kritsky MS (2004) Electrochemical reduction of carbon dioxide on pyrite as a pathway for abiogenic formation of organic molecules. Origins of Life and Evol Biosph. 34, 347-360.
    Telegina TA, Lyudnikova TA, Zemskova YL, Sviridov EA, Kritsky MS (2005) Resistance of 5,10-methenyltetrahydrofolate to ultraviolet radiation. Appl Biochem Microbiol. 41, 275-282.
    Kritsky MS, Belozerskaya TA, Sokolovsky VY, Filippovich SY (2005) Photoreceptor apparatus of the fungus Neurospora crassa. Mol Biol. 39, 514–528.
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Last review: 17 June, 2006
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