Studying Physiological, Morphological, and Cytological Alterations in Prokaryotic and Eukaryotic Cells in Heavy Water

Abstract

In this paper the biological influence of deuterium on cells of various taxonomic groups of prokaryotic and eucaryotic microorganisms realizing methylotrophic, chemoheterotrophic, photoorganotrophic, and photosynthetic ways of assimilation of carbon substrates (methylotrophic bacteria Brevibacterium methylicum, chemoheterotrophic bacteria Bacillus subtilis, photoorganotrophic halobacteria Halobacterium halobium, and green algae Chlorella vulgaris) was investigated at the growth on media with heavy water ( 2 H2O). For all investigated microorganisms are submitted data on growth and adaptation on growth media containing as sources of deuterated substrates 2 H2O, [ 2 H]methanol and hydrolysates of deutero-biomass of methylotrophic bacteria B. methylicum, obtained after the multistage adaptation to 2 H2O. The qualitative and quantitative composition of intra-and endocellular amino acids, proteins, carbohydrates and fatty acids in conditions of adaptation to 2 H2O is investigated. It is shown, that the effects observed at adaptation to 2 H2O, possess a complex multifactorial character and connected to physiological, morphological 143Russian Journal of Biological Research, 2015, Vol. (5), Is. 3 and cytological alterations -the magnitude of the lag-period, time of cellular generation, output of biomass, a parity ratio of synthesized amino acids, proteins, carbohydrates and lipids, and also with an evolutionary level of the organization of the investigated object and the pathways of assimilation of carbon substrates.Keywords: deuterium, heavy water, adaptation, isotopic effects, bacteria, micro algae. IntroductionThe most interesting biological phenomenon is the ability of some microorganisms to grow on heavy water ( 2 H2O) media in which all hydrogen atoms are replaced with deuterium [1, 2]. 2 H2O has high environmental potential in biomedical studies due to the absence of radioactivity and poccebility of detecting the deuterium label in the molecule by high-resolution methods as NMR, IR, and mass spectrometry that facilitates its use as a tracer in biochemical and biomedical research [3]. The average ratio of 1 H/ 2 H in nature makes up approximately 1:5700 [4]. In natural waters, the deuterium is distributed irregularly: from 0,02-0,03 mol.% for river water and sea water, to 0,015 mol.% for water of Antarctic ice -the most purified from deuterium natural water containing in 1,5 times less deuterium than that of seawater. O = 1894 . 10 -6 (1894 ppm). In surface waters, the ratio 2 H/ 1 H = ∼(1,32-1,51) . 10 -4 , while in the coastal seawater -∼(1,55-1,56) . 10 -4 . The natural waters of CIS countries are characterized by negative deviations from SMOW standard to (1,0-1,5) . 10 -5 , in some places up to (6,0-6,7) . 10 -5 , but however there are also observed the positive deviations at 2,0 . 10 -5 .The chemical structure of 2 H2O molecule is analogous to that one for Н2O, with small differences in the length of the covalent H-O-bonds and the angles between them. The molecular mass of 2 H2O exceeds on 10% th...

Biosynthesis of 2H-labeled Photochrome Trans-membrane Protein Bacteriorhodopsin by Halobacterium Halobacterium Halobium

“…Therefore, to obtain reproducible results it was necessary to chromatographically isolate individual derivatives of [ 2 H] amino acids from the protein hydrolyzate. For this aim was used RP-HPLC on on octadecylsilane silica gel Silasorb C18, the effectiveness of which was confirmed earlier by separation of a mixture of methyl esters of N-Dns-derivatives [ 2 H]amino acids from other microbial objects as methylotrophic bacteria and microalgae [20]. The method was adapted to the conditions of chromatographic separation of a mixture of methyl esters of N-Dns-[ 2 H]amino derivatives of BR hydrolyzate comprising in optimization of eluent ratios, the gradient type, and the rate of gradient elution from the column.…”

Studying of Phenomenon of Biological Adaptation to Heavy Water

“…Numerous studies with various biological objects in 2 H2O, proved that when biological objects being exposed to water with different deuterium content, their reaction varies depending on the isotopic composition of water (the content of deuterium in water) and magnitude of isotope effects determined by the difference of constants of chemical reactions rates kH/kD in H2O and 2 H2O. The maximum kinetic isotopic effect observed at ordinary temperatures in chemical reactions leading to rupture of bonds involving hydrogen and deuterium atoms lies in the range kH/kD = 5-8 for C-H versus C-2 H, N-2 H versus N-2 H, and O-2 H versus O-2 H-bonds [22]. Isotopic effects have an impact not only on the physical and chemical properties of deuterated macromolecules in which H atoms are substituted with 2 H atoms, but also on the biological behaviour of biological objects in 2 H2O.…”

“…Various compositions of [U-2 H]MeOH and 2 H2O were added to growth media M9 as hydrogen/deuterium atoms could be assimilated both from MeOH and H2O. The maximum deuterium content was under conditions (10) and (10") in which we used 98 % (v/v) 2 H2O and 2 % (v/v) [U-2 H]MeOH. The even numbers of experiment (Table 1, expts.…”

“…This is observed even while using natural water with an increased content of 2 H2O or 1 H 2 HO [9]. Bacteria can endure up to 90 % (v/v) 2 H2O, plant cells can develop normally in up to 75 % (v/v) 2 H2O, while animal cells -up to not more than 30 % (v/v) 2 H2O [10]. Further increase in the concentration of 2 H2O for these groups of organisms leads to the cellular death [11], although isolated cell"s cultures suspended in pure 2 H2O exert a strong radioprotective effect in 2 H2O-solutions towards -radiation [12,13].…”

“…The traditional method for production of deuterium labelled compounds consists in the growth on media containing maximal concentrations of 2 H2O and deuterated substrates as [ 2 H]methanol, [ 2 H]glucose etc. [15,16]. During growth of cells on 2 H2O are synthesized molecules of biologically important natural compounds (DNA, proteins, amino acids, nucleosides, carbohydrates, fatty acids), which hydrogen atoms at the carbon backbones are completely substituted with deuterium.…”