Дата публикации: 15 сентября 2018
Автор: Vladimir GOLDMAN →
Публикатор: Шамолдин Алексей Аркадьевич
Рубрика: RUSSIA (TOPICS) →
Номер публикации: №1536958771 / Жалобы? Ошибка? Выделите проблемный текст и нажмите CTRL+ENTER!
Vladimir GOLDMAN, (c)
To begin with the beginning-the central objective of the scientific discipline of biophysics consists in the explanation of biological phenomena in terms of the laws of physics and using its methods. Looking back into history one finds out that the science of biophysics began to take shape back in the 19th century, although its emergence into a scientific discipline in its own right with all of its theoretical postulates, terminology, and experimental techniques took place relatively recently.
From the beginning the traditional biophysics was restricted to the studies of the molecular, cellular and organism's levels of organization of living objects. The range of problems within the complex systems under consideration included control of biological processes at the level of a concrete organism and studies of the impact upon organisms of physical factors of different nature. Over the years the range of biophysical problems under consideration continued to grow as a result of the introduction of more advanced methods used for the studies of living objects.
Russia has only two specialized centers of biophysics research today, one of which is the RAS Institute of Biophysics of the Cell located in Pushchino near Moscow. It was set up in 1952 and is headed now by the RAS Corresponding Member G. Ivanitsky. The other is the Krasnoyarsk Institute of Biophysics of the Siberian Branch of the Russian Academy whose director is the RAS Corresponding Member, A. Degermendzhi and it is only this latter center which is conducting biophysical research of ecological orientation, so to speak. And although its initial studies were focused on populations of certain groups of cells, the methods used for their analysis were later logically transferred to studies of bigger biological systems.
The Institute of Biophysics of the RAS Siberian Branch traces its origin to a lab of the same name which was set up back in 1957. After its scientists branched out into several new fields of research, a formal decision was taken on July 1, 1981, to reorganize the lab into an independent scientific center with Academician I. Terskov being appointed its first director.
Today the Institute has 9 labs and two departments, which are all working in one general direction. A fair measure of the research potential of the Center is the composition of its staff which includes 1 Academician, 1 Corresponding Member of the Academy and 15 Doctors and 45 Candidates of Sciences.
The foundation of biophysics research in Krasnoyarsk was laid by studies of Academician I. Terskov and RAS Corresponding Member (later full Member) I. Gitelzon, who investigated the regularities of functioning of blood cells populations. Later on this approach was further extended to single-cell organisms and provided the basis for the development of both the theory and technique of uninterrupted cultivation of microalgae and bacteria under controlled conditions. In this way the Krasnoyarsk researchers formulated, and later developed, a new trend in the biophysics of supra-organic systems which paved the way to an integrated approach to the diagnostics of states of biological systems of different levels of organization and complexity.
Theorists and experimentators demonstrated the possibility of producing stable biophysical systems of continuous, or sustained, biosynthesis. The "working matter" therein were living organisms, and the control of the regime of their functioning was carried out automatically in keeping with sensor data on the state of the
organisms and their habitat. This made it possible to develop within a relatively short span of time automated biotechnical systems of parametrically-controlled biosynthesis of organisms of different levels such as lower and higher phototrophs, lithoautothrophic and heterothrophic bacteria, yeasts, protozoa, higher plants, isolated organs and tissues and also artificial biocenoses and microecosystems.
Taking advantage of flow-through experimental systems, scientists worked out a theory of stability and controllability of the composition of microbial populations. They also proved theorems on the connection of the number of the existing populations with biochemical factors controlling their growth, formulated the criteria of assessment of inter-population metabolic interactions and formulated the energetic principle of microevolution of microbial populations.
The results thus obtained demonstrated the possibility of making use of the vast potential of a genetically conditioned program of growth and biosynthesis of organisms at maximum intensity On the basis of the parametric management of biosynthesis scientists developed a closed system of life-support for man (SLS). The main objective of experiments with this system consisted in assessing the regularities of the functioning of the biosphere. In more practical terms SLSs provide for the comfort of space crews and people under the extreme conditions of arctic latitudes, deserts, high mountains, underwater operations, etc. The Institute of Biophysics of the RAS Siberian Branch is a pioneer in studies with the use of closed ecosystems.
Next on our list is the BIOS system. It takes pride of place not only of the Institute, but of Russian science as a whole. In 1964 scientists using this system pioneered a closed two-stage life- support system of gas exchange known as "man-chlorella". In 1965 it was used for a short-circuit experiment on water, and 1968 saw the first experiments with a three-component system "man- microalgae-higher plants". The results helped to develop an experimental complex BIOS-3 representing a closed ecological life-support system for man with autonomous control. Experiments with the BIOS-3 system with the participation of a three-men crew lasted for half a year with the system being absolutely autonomous in terms of gas and water and with the "recovery" of up to 80 percent of the crew's consumption of food.
The main fundamental objective of the system consists in studying the mechanisms of stability of the biological cycle of substances in biosphere-like experimental systems and development of methods of controlling the intensity and the factor of "independence" of the cycle. One can expect that the pragmatic interest in developing closed ecosystems including man will continue to grow in connection with economic uses of the ocean, outer space and the development of what we call autonomous habitats for humans.
A special place in the Institute studies headed by Academician Gitelzon is taken by glowing marine microorganisms and the phenomenon of bioluminescence.
The main object of studies at the Institute were glowing bacteria. These studies were very intense and covered many areas - from the geography of habitation in the sea and models of symbiosis with animals to the fine details of the molecular organization of a luminescent system and its genetic regulation mechanism.
As has been proved by the findings of many expeditions, glowing bacteria occur all over the World Ocean - from the tropics to the polar latitudes and from the surface to depths of several thousand meters. Luminescent bacteria were isolated from sea water, from the skin of marine animals and fish bowels or as symbionts of the inner and outer micromedia of fish, and cephalopoda.
The year 1987 saw the establishment of the Department of Biotechnology Its main objective was organizing and maintaining Russia's only collection of cultures of glowing bacteria which was started back in the 1960s. Studies were conducted of the properties of these bacteria and regularities of their glow were established. On the basis of the lyophilized glowing bacteria and the luciferase enzymic system isolated from them methods were suggested for express bioluminescent analysis for medical uses, environmental control and control of biotechnological processes.
One of the looming ecological problems today as recognized by the international community at the 1992 UN Conference in Rio de Janeiro is the threat of diminishing biodiversity. From the point of view of functional ecology its negative consequences can include upsets in the natural cycles of matter circulation, "drop-outs" of trophic links, especially among reducents of xenobiotics. Therefore the main problem is this: how can we maintain a stable circulation of substances and what are the mechanisms of such biological consistency? Knowledge of the organization of a closed ecosystem with minimal diversity will serve as a kind of a parameter for the "bottom limit of diversity" (BLD) below which the survival of the biosphere will be impossible.
For their studies of the BLD problem our scientists can use the ecosystems of salt lakes in the south of Siberia with their limited diversity of species. The most effective results will be obtained from studies of sulphur circulation in the ecosystem of the medicinal Shira Lake (about 15 varieties) with its 100-year old history of observations of the water composition dynamics. Generalizing their own field data and building a mathematical prognostication model of sulphur circulation will make it possible to:
-build a mathematical model of circulation of the basic elements (C-N-S-P) in the system of "surface-body of water-bottom";
-establish the conditions of stability of cycles of the main elements with respect to typical natural conditions (illumination, anthrpogenic discharge, flows at phase borders, etc.);
-link the "blossoming" of algae to the sulphur cycle;
-establish a connection between the stratification of the hydrosulphur zone and the organic load upon the lake;
-work out ecologically effective scenarios for the preservation of the ecosystem of Lake Shira and other lakes in Khakasiya.
Taking decisions on nature conservation measures for this lake requires, above all, knowledge about the relative ecological efficiency of all the suggested scenarios of water utilization. The biophysical approach suggests solving such problems of prognostication with the help of a mathematical model of the lake and using it for an assessment of all the possible scenarios. This should help experts to evaluate the ecological efficiency of the proposed water conservation measures and establish the succession of their implementation (bearing in mind their cost).
Essential in such an approach is not some abstract modelling, but an organic combination of theoretical, experimental and field results of the studies for the prognostication of water quality in bodies of water in different water usage scenarios. A field station of the Institute on Lake Shira can serve as an example or the starting point of a permanent chemico-biological station for monitoring other lakes of this region.
For example, in prognosticating the "blooming" of the Kantatsky artificial lake the theoretical model "asserted", contrary to expectations, that the main procedure for reducing the flowering of algae should be linked not with a reduction of surface discharges, but with suppressing the outflows of phosphorus from bottom sediments.
For the past several years our scientists have been trying to assess the scale of radioactive contamination of the Enisei by studying samples taken at different distances downstream from the Mining and Chemical Plant which belongs to the RF Ministry of Atomic Industry. Scientists are exper-
imentally assessing the rate of absorption and release of radionuclides by various water organisms. These laboratory studies also cover transuranium elements.
An important object of ecological biophysics are microorganisms- one of the basic components of the biosphere. Since the foundation of the Institute its researchers have been engaged in biotechnological studies with their results being used in several areas. This primarily includes studies linked with the prospects of biosynthesis of what are called bio-destructible polymers. Discovered back in the 1950s and little studied microorganisms with a unique type of metabolism (chemolithoautothrophic hydrogen-, CO- and ferro-oxidizing bacteria) became an object of active studies in the 1970s. On the basis of these microorganisms our scientists have developed some unique and effective biosystems for obtaining proteins of single-cell and destructible thermoplastic biopolymers. One of the advantages of the proposed methods consists in the possibility of obtaining polymers as a result of bacterial chemosynthesis on hydrogen. As has been demonstrated, polyoxyalkanoates can find applications not only in the food industry (packaging material), but also in medicine (organs transplantations, suture material), radioelectronics and instrument-making industry.
Active studies are now under way in Krasnoyarsk in connection with the problem of waste-water purification and bacterial leaching of ores which will remain important for decades to come. Studies of the functioning of communities of microorganisms and the protozoa as a microbiological barrier for the prevention of environmental pollution provided the basis for the newly-developed and practically important technologies of biodegradation of phenols, compounds of the naphthene series and aniogenic surface-active substances in industrial effluents.
For studies of matter circulation in closed ecosystems an experimental model has been developed for the transformation of vegetable wastes, including higher plants, fungi, worms and microorganisms. Technology has been developed for the processing of vegetable wastes into soil-like substrate (biohumus). For studies and adjustments of technologies of purification of liquid industrial wastes and bacterial leaching of metals special units are being designed, including industrial pilot-plants.
The progress of biotechnology is closely linked with broad uses of recombinant DNA and can help resolve many burning problems in farming, health protection and protection of the environment. However, accidental introduction of transgenic microorganizms (TM) into natural ecosystems can trigger off uncontrolled propagation of recombinant genes. And even with the deliberate TM introduction it is not always that the expected effect can be achieved. Our scientists are working on a comprehensive approach to the studies of transgenic microorganisms aimed at the risk assessment of the application of modified microorganisms and their likely impact on the functioning of ecosystems.
Our scientists are successfully developing ecological biophysics with a view to resolving a set of important problems in the near future. These include: theoretical-experimental solution of the problem of similarity and scaling of ecosystems, including biosphere-like systems; development of experimental-theoretical approaches in modelling of biosphere-like systems and the identification of specific laws of stability of systems with a biological cycle; modelling of the cycle of substances in real water ecosystems; formulation of the hierarchy of laws of closure, or locking, from single-cell symbionts ("zoochlo-rella") to the biosphere. Belonging to the same range of studies is the establishment of new modes of management of water ecosystems (control of "water bloom") by means of the introduction of new species (what is called biomanipulation); development of methods of remote sounding of water ecosystems involving methods of mathematical modeling of ecosystems dynamics; completion of a prognostication model of the radio-ecological conditions of the Enisei on the basis of expedition findings of the recent past (Institute of Lymnology, RAS Siberian Branch) and also on the basis of current radiation field measurements and experimental data.
Our researchers have substantiated the possibility of an indirect approach to the diagnostics of the conditions of large natural ecosystems by measuring disturbances introduced into the physical field of the environment by natural processes occurring in the biosphere and also resulting from anthropogenic impacts. For the remote measurements of the optical characteristics of water masses and vegetation groups special instruments have been developed which can obtain data, at the rate of the carrier movement, on the primary productivity of marine bio-cenoses, agricultural crops and forests and on water pollutions.
Studies on the Enisei, Baikal, the Caspian Sea and in the Pacific and the Indian Oceans have proved the applicability of the methods suggested by the Krasnoyarsk scientists for various hydrooptical conditions. Formed on this basis have been the scientific-social projects like "Ecology of the World's Biggest Rivers", "Green Wave" and programs "Chlorophyll in the Biosphere" and "Clean Enisei", which are supported by the Hydrological Society of UNESCO, the RAS working group "Earth Sciences", the US National Astronautics Federation and other agencies.
Nauka v Sibiri (Science in Siberia), 2001
Опубликовано 15 сентября 2018 года
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