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1.
Seven strains of Gram-positive microorganisms capable of forming endospores have been isolated from soils of the region of potassium salt mining (Berezniki, Perm krai) by the method of enrichment cultures. Their typing by means of REP- and BOX-PCR has shown that four strains—I23 (= VKM V-2504), I26 (= VKM V-2505), I27, and I28—are of the same genogroup (type I), while strains SN501 (= VKM V-2508), I10b (= VKM V-2507), and I12b (= VKM V-2506) represent three different genogroups (types II, III, and IV, respectively). A phylogenetic analysis of 16S rRNA gene sequences has shown that strains I10b and SN501 belong to the genus Paenibacillus, and the remaining strains, to the genus Bacillus. These bacteria are tolerant of high salinity and alkalinity: they can grow at pH 7.0–9.0 and NaCl content of 90–110 g/l in the culture medium. They are also capable of utilizing diesel fuel and individual aromatic and aliphatic hydrocarbons.  相似文献   

2.
Microorganisms capable of degrading monocyclic and polycyclic aromatic hydrocarbons and several chlorinated aromatic compounds were isolated from soils polluted with industrial waste from chemical plants. They were identified as representatives of the genera Pseudomonas, Flavobacterium, Alcaligenes, Rhodococcus, Microbacterium, Cellulomonas, Arthrobacter, and Brevibacterium. Among them, bacteria capable of utilizing xenobiotics in a wide range of ambient temperatures and pH and in the presence of high sodium chloride concentrations were revealed.  相似文献   

3.
Two species or strains of Penicillium were isolated by the enrichment technique from areas exposed to oil seepage. Infrared spectroscopy revealed that, after eight days of treatment, these microorganisms were capable of degrading paraffinic and aromatic hydrocarbons in media made with Mediterranean waters. They could not, however, degrade crude oil.  相似文献   

4.
Hydrogen produced by microorganisms is a topic of growing interest because of its potential for derivation from several agro-industrial by-products. In this study, we evaluated the hydrogen production of strains of genus Clostridium (Clostridium acetobutylicum and Clostridium butyricum) using glycerol as a carbon source. Fermentation studies were conducted using three initial concentrations of glycerol: 10, 30 and 50 g/L. The micro-organism growth kinetics and the amounts of solvents and gases were recorded over 48 h. The strain C. acetobutylicum exhibited the best results in terms of hydrogen production, the highest production yield (Y p/s) of 0.37 mol H2/mol glycerol and the highest level of productivity (0.75 mg H2/(L·h)). Based on these results, it is reasonable to conclude that glycerol could be effectively exploited as a carbon source for hydrogen production, which adds value to this primary by-product of standard biodiesel processes.  相似文献   

5.
The diversity of bacteria metabolizing nitriles of carbonic acids was studied in soils of the Perm region affected by human activities. Effective methods for selective isolation of cultures possessing the nitrile hydratase and nitrilase activities were developed. Most microorganisms capable of utilizing nitriles were Grampositive Nocardia-like bacteria of the genus Rhodococcus. Isolates with a detectable nitrilase activity were also represented by Gram-negative forms (Gram-negative aerobic/microaerophilic bacilli and cocci of the genera Pseudomonas, Azomonas, Azotobacter, and Acidovorax). Two enzyme systems for nitrile hydrolysis were found in 27% of cultures. The nitrile hydratase and nitrilase activities of the studied strains exceeded these enzymatic activities in bacteria isolated from native soils, which indicates that natural selection of saprophytic microflora occurs in chemically altered soils.  相似文献   

6.
The research was focused on the slurry-phase biodegradation of naphthalene in soil. Among ex situ techniques, the slurry phase offers the advantage of increased availability of contaminants to bacteria. From naphthalene contaminated soil, a Pseudomonas putida M8 strain capable to degrade naphthalene was selected. Experiments were performed in a stirred and oxygenated reactor. In this study, the influence of air flow rate and agitation rate on volatilisation and biodegradation of naphthalene was investigated. The hydrocarbon disappearance, the carbon dioxide production, and the ratio of total heterotrophic and naphthalene-degrading bacteria was monitored. The results obtained confirm that the selected bioremediation technology is successful in the treatment of contaminated soils.  相似文献   

7.
There are only few studies defining persistent organic pollutant (POP) concentrations in various fat compartments from living obese individuals. The present study has therefore determined the concentrations of various classes of organohalogenated compounds, such as dichlorodiphenyltrichloroethane and its metabolites (DDTs), chlordane compounds (CHLs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecanes (HBCDs) in visceral fat (VF: n = 52) and subcutaneous abdominal fat (SF: n = 52) samples collected in 2010–2012 from obese individuals in Belgium. Organohalogen compounds were detected in all fat samples in the decreasing order of their concentrations: PCBs > DDTs > HCHs > CHLs > HCB > HBCDs > PBDEs, suggesting that Belgians have been widely exposed to these contaminants. The levels and the patterns of POP distribution in VF and SF tissue depots were not significantly different. Concentrations of PCBs (VF/SF; median: 285/275 ng/g lw) and DDTs (VF/SF; median: 150/155 ng/g lw) were the major POPs in all fat samples. Concerning PCBs, PCB 153 (VF/SF: 27/26%) was the most dominant congener, followed by PCB 180 (VF/SF: 17/18%), PCB 138 (VF/SF: 15/14.5%) and PCB 170 (VF/SF: 8.1/8.4%) to the sum PCBs, respectively. Levels of HBCDs (VF/SF; median: 4.0/3.7 ng/g lw) and PBDEs (VF/SF; median: 2.6/2.7 ng/g lw) were 1–2 orders of magnitude lower than those of PCBs and DDTs. Among PBDEs, BDE 153 (VF/SF: 31/34%) was the dominant congener, followed by BDE 47 (VF/SF: 26/23%), BDE 154 (VF/SF: 16/16%), BDE 100 (VF/SF: 10/11%) and BDE 99 (VF/SF: 9/9%). To our knowledge, this is the first report on HBCD concentrations in Belgian human fat tissues. Total PBDE and HBCD levels in human fat samples could not be correlated with age. In agreement with the literature, a significant correlation (p < 0.05) between age and the concentration of PCBs (r = 0.828), DDTs (r = 0.640), HCHs (r = 0.666), CHLs (r = 0.534) and HCB (r = 0.754), was observed in the present study. Levels of DDTs, HCHs, HCB and CHLs were also significantly correlated to each other, suggesting that they share similar exposure routes. Correlation with computed tomography (CT) scan data revealed that VF and VF/SF ratios are positive for most of the POPs, such as PCBs, PBDEs, p,p′DDE, CHLs, β-HCH, and HCB. To our knowledge, this study is the first to assess the relationship between POP levels in adipose tissue and markers of abdominal adiposity, determined by CT.  相似文献   

8.
The population dynamics of the gypsy moth and the genomic DNA of the nuclear polyhedrosis virus (NPV) pathogenic for this insect were simultaneously studied using nucleic acid molecular hybridization (NAMH). It was demonstrated that population outbreaks of the gypsy moth were accompanied by an increase in its sensitivity to NPV and in the genetic polymorphism of NPV strains circulating in the insect populations. The hybridization activity of the virus strains isolated at the phase of gypsy moth population growth was significantly higher (p < 0.001) than the activity of the strains isolated at the phase of population decrease.  相似文献   

9.
In four modern trees, hydrogen and oxygen isotope ratios track the modern temperature records.In a 2000-yr sequence of a Japanese cedar, there are the same periodicities of variation of D/H and O18/O16 as have been found in O18/O16 in a Greenland ice well.The same periodicities are found in uranium and organic carbon concentrations versus depth in a sea core from the Santa Barbara Channel, and in carbon-14 variations in a sequence of Bristlecone pine from southern California.In a 2000-yr sequence of Japanese cedar and in a 1000-yr sequence of European oak D/H and O18/O16 are related to each other by a slope of 8, just as they are in world-wide precipitation.In a 72-yr sequence of Sequoia gigantea, measured year by year for its oxygen isotope ratios, the 10.5-yr cycle of sunspot numbers found, but not the 21-yr cycle of sunspot magnetism; this we believe indicates that the sun is affecting the earth's climate with non-magnetic particles, probably photons.All these phenomena are related to periodic changes in sea surface temperature caused by periodic changes in the sun.  相似文献   

10.
Susceptibility of the Colorado potato beetle to entomopathogenic fungal infection has been studied for the first time in the Republic of Bashkortostan and shown to be associated with other population genetic characteristics of the species in this region. A new strain of Beauveria bassiana, Ufa-2, has been isolated and tested for virulence in comparison to B. bassiana strains isolated from other insect species and maintained in the collection of the Institute of Systematics and Ecology of Animals, Siberian Branch, Russian Academy of Sciences.  相似文献   

11.
The endemic species Lagotis uralensisis characterized with regard to the stages of ontogeny, population structure and dynamics, and the ways of species adaptation to growing in the form of small isolated populations in high mountains.  相似文献   

12.
A comparative analysis of reproductive behavior has been performed in the steppe lemming (Lagurus lagurus) and narrow-skulled vole (Microtus gregalis). The results show that the species are similar in certain behavioral features indicative of the stability of mating pairs. However, in the narrow-skulled vole, unlike in the steppe lemming, mature males in olfactory tests show preference for receptive sibling females versus non-kin females. Probably, it is the absence of the incest taboo that allows the involvement of young of the year in reproduction within growing family groups and accounts for “coloniality” of the species.  相似文献   

13.
The natural microflora of Middle Siberian karst cavities, which comprises psychrotolerant bacteria and fungi capable of growing at 3–15 and 3...+28°C, respectively, has been studied. Bacteria are ubiquitous in caves, their count varying from 103 to 107 cells/g ground. The bacteria have been identified as Pseudomonas, Arthrobacter, Bacillus, and coryneform bacteria. Fungi have been found in places exposed to increased anthropogenic impact, their count being as large as 106 to 107 cells/g ground. Mucor, Penicillium, and Chrysosporium were dominant fungal genera.  相似文献   

14.
Variation of bilateral leaf structures in Middle Ural cenopopulations of the weeping birch (Betula pendula Roth.) growing in gradients of industrial pollution was studied to test the efficiency of a new method of population and individual phenogenetic monitoring allowing an indirect assessment of developmental destabilization by segregating the variance of total asymmetry (TA R 2) into its additive components, the variances of fluctuating asymmetry (FA R 2) and directional asymmetry (DA R 2). The method was tested in the impact zones of two copper-smelting plants in the Middle Urals. The degree of impact was characterized by the index of technogenic pollution (ITP) reflecting the average total contents of 15 water-soluble pollutants in snow samples. The level of asymmetry was estimated from the numbers of denticles with incoming veins (dentovenal elements) on the left and right leaf margins. Spearman’s coefficient of rank correlation between the group values of variance in fluctuating asymmetry (FA R 2) and corresponding ITP values reached r S = 0.914 (p < 0.001), providing evidence that the method is highly appropriate for ecological indication of the phenogenetic response of trees to environmental pollution.  相似文献   

15.
Former dredging sites were studied in the taiga zone of the Amur region (in Khabarovsk Krai). The involvement of Larix cajanderi in plant succession on dredging waste dumps was revealed. Some morphological-anatomical parameters of L. cajanderi needles were compared in trees growing on the dumps and in adjacent open larch stands on waterlogged peaty soils.__________Translated from Ekologiya, No. 4, 2005, pp. 259–263.Original Russian Text Copyright © 2005 by Osipov, Burundukova.  相似文献   

16.
The allozyme analysis of six local populations of Pinus mugo Turra and six populations of P. sylvestris L. in the Ukrainian Carpathians, Swiss Alps, and Schwarzwald has shown a higher polymorphism and greater interpopulation differentiation of the Carpathian group of P. mugo populations compared to the Alpine group (Nei’s genetic distance DN 78 at the level of geographic population group is −0.023). A genetic differentiation of DN 78 = 0.049 between these populations, which are isolated by a distance of more than 1000 km, has been found. This confirms the existence of the subspecies P. mugo ssp. mugo and P. mugo ssp. uncinata in the Carpathians and Alps, respectively. The hypothesis is put forward that the former subspecies has been formed in the Balkans and the latter, in the Pyreneans. It has been demonstrated that regional populations and geographic groups of P. sylvestris are less differentiated than those of P. mugo.  相似文献   

17.
In experiments performed in aquariums, the daily consumption of Chara vulgaris alga by crayfish (Astacus astacus L.) has been determined. These quantitative data have been used to make a prognosis of the effect of the A. astacus population on the biomass of macrophytes in Lake Berezovo (Pskov oblast). The density of the crayfish population and the biomass of higher aquatic vegetation in the lake have been determined in field studies. Extrapolation of the results of laboratory experiments to a natural water body has shown that crayfish are capable of controlling no less than 40% of submersed macrophytes in the area used by their population.__________Translated from Ekologiya, No. 4, 2005, pp. 300–305.Original Russian Text Copyright © 2005 by Kholodkevich, Shumilova, Fedotov, Zhuravlev.  相似文献   

18.
Accelerated aging of Drosophila strains with impaired detoxification of free radicals (Sod) and DNA repair (mus-210) under illumination as compared to the wild type has been demonstrated. In contrast, in a strain carrying a defective homolog of mammalian gene PCNA, the life span increases under conditions of round-the-clock illumination compared to constant darkness. The first review of the possible mechanisms underlying the effect of the illumination regime on the life span is presented, with special emphasis on the roles of the disturbance of normal circadian rhythms, increase in fecundity and physical activity (metabolic rate), and the neuroendocrine control of the insulin/IGF-1 pathway.  相似文献   

19.
Comparative allozyme analysis of 26 marginal island populations of Pinus sylvestris L. and 20 populations from the center of the species range has confirmed, at the species level, the Wright-Dubinin “island model” of automatic genetic processes and Mayr’s hypothesis about homozygotization of small isolated populations at range boundaries. It has been shown that the polymorphism of isolated populations sharply decreases when their area is reduced below 15–20 km2 and increases to the level observed in the center of the range when the population area exceeds 50–100 km2. A chorogenetic classification of marginal P. sylvestris populations is proposed.  相似文献   

20.
The capacity of species for expansion and colonization of new habitats is a key condition for the maintenance of their populations. In this study, specific features of the reproductive potential have been analyzed in Lobaria pulmonaria populations growing under contrasting climatic conditions. Certain ecological determinants governing the development of this lichen species have been revealed.  相似文献   

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