Boreskov Institute of Catalysis of the Siberian Branch of Russian Academy of Sciences
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- References [1]. Ostrovskii V. E . , Kadyshevich E. A. Russ. J. Phys. Chem. 2000, 74
- PP‐10 FUNGAL‐LIKE ELEMENTS IN THE CONSTRUCTION OF THE RIPHEAN UNICELLULAR MICROFOSSILS German T.E., Podkovyrov V.N.
- PP‐11 COSMIC PERIODICITY IN PHANEROZOIC GEOLOGY Glazachev D.O.
- PP‐12 GTF2I DOMAIN: STRUCTURE, EVOLUTION AND FUNCTION Gunbin K.V., Medvedeva I.V., Ivanisenko V.A., Ruvinsky A.O.*
- PP‐14 GENERATION OF MODERN MINERAL‐BIOLOGICAL SYSTEMS UNDER CONTINENTAL CONDITIONS Ivanova V.L. 1 , Barinov N.N. 1
PP‐9 thousands of starting models have been sampled with this procedure for each of the three types of clathrate hydrate structures. The principal results and conclusions of this work are as follows: – Removing guest molecules from cavities does not collapse polyhedral water structure: it stays stable being a local energy minimum in the global configuration space. This is an argument to regard such a predicted guest‐free host structure as a ‘polyhedral ice’ polymorph; its density is only about 10% less than the density of hexagonal ice. – The lowest‐energy structures demonstrate H‐bond networks perfectly complementing the Bernal ‐ Fowler ‘ice rules’ of with standard H‐bond geometric parameters. The most stable polyhedral ice structure of the cubic‐II type was found centrosymmetric and face centered (i.e., space group F‐1), with energy E = –56.15 kJ/mol. It is 0.04 and 0.33 kJ/mol more stable than the lowest‐energy P‐1 polyhedral ice structures of the cubic‐I and hexagonal‐I types, respectively. For comparison, the hexagonal ice polymorph, as calculated by optimization of the Bernal–Fowler model [4], is of E= –56.99 kJ/mol, Though, we have to admit that the number of P1 starting models sampled by us is small as compared to the total number of proton configurations, amounting, e.g., for cubic‐I to as much as 17 millions [5]. – In addition, the global search detects numerous less stable structures as local energy minima. They are characterized by the presence of one or more local ‘defects’, where significant deviations from normal hydrogen bond geometry take place resulting in local violation of the ice rules. Inspecting still less stable structures reveals one or more hydrogen bonds broken, thus opening ‘windows’ between the adjacent cavities. – We conclude that the ability of water molecules for self‐assembling into the polyhedral structures stems from the fine peculiarities of molecular structure and the intermolecular potential of the water molecule rather than those of guest one. Generally, this work demonstrates clearly the prospects of our crystal‐structure prediction technique [3] as an instrument to help understand poorly resolved experimental structural data, such as those where crystal disorder is inevitably present. Moreover, it gives a possibility to compare different experimental structural observations on theoretical grounds and look further beyond the experiment to predict yet undiscovered phases. 146 PP‐9 147 Acknowledgement. This work was supported by the Program of presidium RAS No. 15 (09‐П‐5‐1009) and Russian Foundation of Basic Research (Nos. 08‐05‐00993, 11‐03‐00870). References [1]. Ostrovskii V. E., Kadyshevich E. A. Russ. J. Phys. Chem. 2000, 74, 1114–1124. [2]. Jorgensen W. L., et al. J. Chem. Phys. 1983, 79, 926–935. [3]. Dzyabchenko A.V. Russ. J. Phys. Chem. A. 2008, 82, 1663–1671. [4]. Bernal J.D., Fowler R.H. J. Chem. Phys. 1933, 1, 515‐548. [5]. Kirov M.V. Crystallography reports 2010, 55, 353‐361. PP‐10 FUNGAL‐LIKE ELEMENTS IN THE CONSTRUCTION OF THE RIPHEAN UNICELLULAR MICROFOSSILS German T.E., Podkovyrov V.N. Institute of Precambrian Geology and Geochronology RAS, Makarova emb., 2, St.‐Petersburg 199034, Russia, e‐mail: vpodk@mail.ru Precambrian microfossils are useful in comparative studies of such fundamental aspects as the transition from unicellular to multicellular organization. The specific population of the Riphean unicellular organisms has been described from ~1Gyr sediments (Lakhanda Group, Uchur‐Maya region, SE Siberia). They have been recorded in shales and consistently associated with water‐deposited sediments. Unicells having a hollow shell of highly varied shape (spherical, ellipsoidal, elongate or sometimes polygonal) are composed of an organic substance and show net‐like distribution. A considerable number of Precambrian genera remained of undetermined affinity and genera defined on morphology only, without implication as to relationships, it is undesirable that they should be classed into the Linnaean hierarchy of orders and families. It is clearly preferable that any classification, adopted should give no false impression of any natural relationship and should facilitate the easy transfer away of genera when their affinities came to be determined. The lakhandinian microfossils were interpreted as probable yeasts that have evidence in growth habit, general morphology, mode of reproduction commonly can be discerned features that provide a basis for comparison of extant and fossil taxa. Riphean unicells display the coincidence of their morphology, the mode of typical multilateral budding of Saccharomyces and give additional evidence of the very early existence of such biological organization. These organic‐walled fossils have been described as Eosaccharomyces ramosus Herm. (Hermann, 1979). Precambrian unicellular organisms extremely numerous and show innovations in biologic organization involved in the evolutionary transition from a single cell to multicellular pseudo tissue‐like microcolonies. Adjacent or loosely connected cells in these colonies tend to be similar texture and color, but differ in their diameter and shape. The connection between adjacent cells in colonies is usually with indication of cytoplasmic connection. Within an array fossils are equidimensional, but more often with one of the cells two to three times longer than its neighbor and resemble sack‐like body called an ascus. There are some spheroidal structures 148 PP‐10 149 that are much darker (probably thicker walled). The occurrences above mentioned cells suggest the presence of reproductive structures of microfossils. Unicellular organisms have an entirely distinct habit and mode of the formation of numerous multicellular branching colonies that have been organized into asymmetrical, sectorial‐type clusters with different number of budding or divided unicells. Fungi are protists by far the most metabolically diverse eukaryotes that can preserve some diagnostic features of life cycle and morphology. Fossil records give an opportunity to suggest Ascomycota radiation events in the Proterozoic era. The study was performed with the support of Program 25 of the Presidium of RAS. References [1]. Hermann T.N. (1979)/ Records of Fungi in the Riphean. In.: B.S.Sokolov (ed.). Paleontologiya Dokembriya i Rannego Kembriya (Paleontology of the Precambrian and Early Cambrian). Leningrad: Nauka. P. 123‐133. PP‐11 COSMIC PERIODICITY IN PHANEROZOIC GEOLOGY Glazachev D.O. Institute of Geosphere Dynamics of Russian Academy of Sciences (IDG RAS), Moscow, Russia, GlazachevD@gmail.com There is cyclisity in many processes, such as the changes in mainlands' structure, variation in biodiversity of species, galaxy influence, impacts of cosmic bodies. The problem of an establishment of the cyclicity and correlation of all those processes discovering has been performed for 50 years. In the present work we search for interrelation of events in biosphere and geospheres of the Earth from comparison of the data on mass extinctions and impacts and data on geological activity for the same period (Phanerozoic). Phanerozoic history contains all extinction events of the “Big Five” (major extinction events by Jack Sepkoski and David M. Raup) — End‐ Cretaceous (65.5 Ma), Late Devonian (205 Ma), End‐Permian (251 Ma), End‐ Triassic (360‐375 Ma), and End‐ Ordovician (440‐450 Ma). In addition, we examine data on Phanerozoic climate change, which kept data on the glacial periods. There are four major periods called glacial periods with lowest average temperature on the Earth defined by 18 O parts per thousand. The results of spectral, wavelet and correlation analysis of data series representing those processes are shown in the report. The conclusion is made that most of them are cyclic, some of the periods are present in all the processes. The galactic causes of the cycles with duration in tens and hundreds millions years are discussed. 150 PP‐12 GTF2I DOMAIN: STRUCTURE, EVOLUTION AND FUNCTION Gunbin K.V., Medvedeva I.V., Ivanisenko V.A., Ruvinsky A.O.* Institute of Cytology and Genetics SB RAS, Novosibirsk State University, Novosibirsk, Russia *The Institute for Genetics and Bioinformatics, University of New England, Armidale, Australia The GTF2I gene family consists of gtf2i, gtf2ird1 and gtf2ird2 genes encoding transcriptional factors and the first two of them involved in Williams‐Beuren syndrome if mutated [1]. The main characteristic of this gene family is the presence of several so called GTF2I repeats. There are 5 such repeats (R) in GTF2IRD1, 6 in GTF2I and 2 in GTF2IRD2. Our aim was to study the molecular evolution of these repeats. We collected the GTF2I repeats from about 20 chordate species from Branchiostoma floridae to Homo sapiens using the information about gtf2i‐like genes from databases and retrieving information from genomes, assemblies and EST collections. Then we reconstructed the phylogenetic networks using Bayesian, maximum likelihood and distance methods, and found that R5 (gtf2ird1) could represents most probable ancestor of all GTF2I repeats. 0.1 gtf2ird1 r4 gtf2i r6 gtf2ird2 r2 gtf2ird1 r2 gtf2ird1 r1 gtf2ird2 r1 gtf2i r1 gtf2ird1 r5 ciona gtf2i r5 gtf2i r2 gtf2ird1 r3 gtf2i r3 gtf2i r4 lancelet gtf2ird1 r : 1 r2 r3 r4 r5 gtf2i r : 1 r2 r3 r4 r5 r6 gtf2i r : 1 r2 We also found that amplification of gtf2i gene repeats (R2, R5, ancestor of R3 and R4) and duplication of gtf2ird1 gene repeats (R4, ancestor of R2 and R1) occurred before Gnathostomata origin. Based on our hierarchical classification of GTF2I repeats and recent research [2] we hypothesize that GTF2I gene family have raised from the two genome duplication events early in vertebrate evolution. 151 PP‐12 152 Comparison of molecular evolution model of the GTF2I family with real data using method implemented in SAMEM [3] discovered several types of statistically rare aminoacids replacements (p≤0.01) which characterized by greatest physicochemical changes. These replacements related with: 1) the divergence between gtf2ird1 R4 and gtf2i R6, 2) the origin of gtf2ird1 R1 and R2 ancestor, and 3) the origin of gtf2ird1 R1 and gtf2i R1 ancestor. We used the program package PDB3DScan for structural alignment to find the differences in the 3D structure of GTF2I repeats in gtf2i, gtf2ird1 and gtf2ird2 genes and identified that those statistically rare substitution mostly situated in loop regions or in the beginning or in the end of helices. We showed that the helix in structure of the first repeat of gtf2i, gtf2ird1, gtf2ird2 is much less conservative then in the other repeats. We also found the unique mutational pattern for each GTF2I repeat that could be caused by their functional specialization (for example, DNA‐binding [4]). This work was supported by RFBR grant No. 09‐04‐01641‐a and Biosphere Origin and Evolution program . References [1]. Bayarsaihan, D. et al. (2002) Genomic organization of the genes Gtf2ird1, Gtf2i, and Ncf1 at the mouse chromosome 5 region syntenic to the human chromosome 7q11.23 Williams syndrome critical region, Genomics, 79:137‐143. [2]. P. Dehal, J.L Boore. (2005) Two Rounds of Whole Genome Duplication in the Ancestral Vertebrate, PLoS Biol., 3:e314. [3]. K.V. Gunbin et al. (2010) A computer system for the analysis of molecular evolution modes of protein‐ encoding genes (SAMEM), Moscow University Biological Sciences Bulletin, 65:142‐144. [4]. S.J. Palmer et al. (2010) Negative autoregulation of GTF2IRD1 in Williams‐Beuren syndrome via a novel DNA binding mechanism, J. Biol. Chem., 285:4715‐4724. PP‐13 DEEP INSIDE INTO VERTEBRATES AND INVERTEBRATES MACROEVOLUTION: THE MOLECULAR EVOLUTION MODES OF STRICT ORTHOLOGOUS PROTEIN SEQUENCES Gunbin K.V., Suslov V.V., Afonnikov D.A. Institute of Cytology and Genetics SB RAS, Novosibirsk State University, Novosibirsk, Russia The molecular evolution modes of 752 orthologous protein groups (OPGs) of vertebrates and of 1736 OPGs of invertebrates were analyzed. In our analysis the OPGs were taken from MetaPhOrs database [1]. The OPGs containing at least one strictly confirmed orthologous sequence without ambiguous characters from each of 20 vertebrate species groups and 9 invertebrate species groups were taken into analysis (Figure 1). Cnidaria and Tunicata were served as outgroup taxa. The ancestral protein reconstruction in each internal tree node of OPG was made using PAML 4 CODEML program [2] (marginal reconstruction) on the basis of the known tree topology (Figure 1) and amino acid replacement matrices calculated by MODELESTIMATOR [3] program. These ancestral sequences were used to calculate the number of observed amino acid substitutions. For each amino acid replacement type we compared the observed number of changes with expected ones under the assumption of a stationary Markov process of protein evolution. Expected replacement numbers were calculated using 1000 computer simulations of OPG molecular evolution by the INDELible program [4], taking into account the peculiarities of the investigated OPGs. Comparison of expected and observed numbers of each replacement type was performed using permutation tests (10 5 permutations). We count the number of random samples, M, in which the frequency of expected changes of a certain type higher than the frequency of observed ones. Thus, the value M/10 5 is the occurrence probability, p, of a certain amino acid replacement type observed by chance. The analysis of R value, the proportion (%) of OPGs with atypical amino acid replacements (p≤0.01), showed that internal tree branches of vertebrate tree with R≥20% strictly correspond to aromorphoses in the vertebrate evolution (Figure 1): 1) the full genome duplications in early stages of vertebrate evolution and actynopterigian fish evolution, 2) the adaptation to terrestrial environments, 3) the origin of Amniota, 4) the divergence of primitive mammals and placental mammals. It is of big interest that the molecular evolution of insects and nematodes were characterized by significant increase in R 153 PP‐13 154 value in comparison with its mean value for vertebrates (Figure 1). The absolute maximum of R value is typical for nematodes. It was shown that the divergence of Insecta and Diptera accompanied by increasing of R (Figure 1) may be due to the emergence of insects‐ angiosperms ecosystems and to the formation of the characteristic Diptera morphology. This study we also conducted the functional comparison of OPGs containing atypical amino acid replacements that allowed us to uncover various features of gene networks molecular evolution on each internal branches of vertebrate and invertebrate trees (Figure 1). B Tunicata Cnidaria Lophotrochozoa Arachnida Paraneoptera Hymenoptera Lepidoptera Drosophilina Culicomorpha 32.5 26.6 21.9 33.6 26.8 Low Chromadorea Caenorhabditis 44.5 18.1 23.2 A Cnidaria Tunicata Amphibia Prototheria Metatheria Lower Primates Catarrhini Hominidae 14.1 11 Lagomorpha Rodentia 10.9 8.4 Insectivora Artiodactyla Chiroptera Carnivora Equidae 9 7.4 7.6 10.2 9.6 Afrotheria Xenarthra 10.1 25.3 15.7 21.8 Aves Squamata 15.7 21.8 24.6 Cypriniformes Tetraodontiformes Smegmamorpha 26.9 27.8 36 Figure 1. Phylogenetic tree of vertebrate (A) and invertebrate (B) species groups. On each internal tree branch the proportion (%) of orthologous protein groups containing atypical, statistically rare (p≤0.01), types of amino acid replacements were shown. This work was supported by RFBR grant No. 09‐04‐01641‐a and Biosphere Origin and Evolution program . References [1]. Pryszcz L.P. et al. (2010) MetaPhOrs: orthology and paralogy predictions from multiple phylogenetic evidence using a consistency‐based confidence score, Nucl. Acids Res., doi: 10.1093/nar/gkq953. [2]. Yang Z. (2007) PAML 4: phylogenetic analysis by maximum likelihood, Mol. Biol. Evol., 24:1586‐1591. [3]. Arvestad L. (2006) Efficient methods for estimating amino acid replacement rates, J. Mol. Evol., 62:663‐ 673. [4]. Fletcher W., Yang Z. (2009) INDELible: a flexible simulator of biological sequence evolution, Mol. Biol. Evol., 26:1879‐1888. PP‐14 GENERATION OF MODERN MINERAL‐BIOLOGICAL SYSTEMS UNDER CONTINENTAL CONDITIONS Ivanova V.L. 1 , Barinov N.N. 1 , Skirina I.F. 2 1 FEGI, FEB of RAS, Vladivostok, e‐mail: fegi@vlad.ru 2 PIG, FEB of RAS, Vladivostok, e‐mail: sskirin@yandex.ru In contrast to the biostagnated systems developed in water basins, the mineral‐ biological systems localized on the land are more irregular, show a greater degree of fortuity, not stable exchange of matters inside the system and with the environment. These properties require specific methods of investigations. In particular, the point‐counter microanalysis will provide more reliable information about chemical processes than a classic analysis of media. The paper presents the results of research of interaction of epilithic and epigenous lichens with ore and ore‐free rocks of the scheelite‐sulfide deposit dumps. Fragments of the oxidized ore are populated with bushy lichen Stereocaulon sp. and crustose lichen, ore‐free area being ignored. Study of the samples, using the electron scanning microscope EVO‐50 XVP with spraying of samples, revealed Stereocaulon sp. growing on hypergene ferruginous crusts and films. More precisely, algae are localized exclusively on crusts, and fungus hyphae occur on crusts and under them and penetrate between mineral fragments. Microanalysis showed that in addition to Fe, S these crusts contain carbon and W. Other admixture elements vary depending on the primary ore composition. On the ore‐free dumps, mainly on the granodiorite fragments, another genus of lichen – Cladonia sp., Cladonia gracilis (L.)Wild) – grows. Here fine fragments of rocks are entangled with fungus hyphae, and algae appear above this boundary layer. In the podetium body there were found the rounded ferruginous inclusions of 1.5‐2 mkm in size. In their morphology they look like pyrite framboids [1]. This can be suggested to be is a result of vital activity of thiobacteria, reworking the sulfides [2]. Minerals, intergrown with lichens, are diverse: quartz, feldspars, pyroxenes, scheelite, and rarely sulfides. Intergrowth is very firm at a macro‐ and microlevel. In the mineral spectra, carbon is present, and their composition stoichiometry is usually destroyed. This 155 PP‐14 156 indicates the chemical exchange, including a probable treatment of the mineral base by the biota ferments. The latter provide the firm “cementation”. So the epilithic lichens use a rock not only as a support for settling. A biomineral system is formed where the chemical interaction of minerals and lichen take place: enrichment of ferruginous films with carbon and thalli with elements of Fe, S, and Si, and in certain cases with Mg, Al, K, and Mn. Heavy metals (W, As, Zr, Ag, Ir) are not used by a growing organism. They are toxic for it, so scheelite, silver, and some sulfides are preserved even through the treatment of them with ferments, and under appropriate conditions they can be accumulated and redeposited to some degree by the lichens. The reported interactions of minerals and lichens characterize the generation of isolated elements of future biogeocoenosis with the individual thus far chemical processes. Download 5.04 Kb. Do'stlaringiz bilan baham: |
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