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11.
Kolombet L. V. Jigletsova S. K. Derbyshev V. V. Ezhov D. V. Kosareva N. I. Bystrova E. V. 《Applied Biochemistry and Microbiology》2001,37(1):98-102
A technology was designed for manufacturing a preparation based on Trichoderma viride Pers ex S.F. Gray that strongly suppresses the development of causative agents of certain plant diseases and displays a growth-stimulating activity. Cultivation of the strain in a liquid medium for 18–24 h produced up to 60 g dry biomass per liter nutrient medium. A marketable form created in this work conserves the activity of the mycelial preparation for six months. The preparation is compatible with insecticides (carbofos, vismetrin, talstar, and applaud) and certain fungicides (such as baitan). Tests performed with the liquid form of Mycofungicid (seeds were treated with this preparation at a dose of 20–30 g per metric ton before sowing) showed its high efficiency in protecting cereal crops from plant pathogens. The incidence of plant diseases decreased by 65%, and crop yields increased by 15–20%. 相似文献
12.
Acceptor specificity of the human leukocyte alpha3 fucosyltransferase: role of FucT-VII in the generation of selectin ligands 总被引:2,自引:2,他引:0
Britten CJ; van den Eijnden DH; McDowell W; Kelly VA; Witham SJ; Edbrooke MR; Bird MI; de Vries T; Smithers N 《Glycobiology》1998,8(4):321-327
The alpha3 fucosyltransferase, FucT-VII, is one of the key
glycosyltransferases involved in the biosynthesis of the sialyl Lewis X
(sLex) antigen on human leukocytes. The sialyl Lewis X antigen
(NeuAcalpha(2-3)Galbeta(1-4)[Fucalpha(1-3)]GlcNAc-R) is an essential
component of the recruitment of leukocytes to sites of inflammation,
mediating the primary interaction between circulating leukocytes and
activated endothelium. In order to characterize the enzymatic properties of
the leukocyte alpha3 fucosyltransferase FucT-VII, the enzyme has been
expressed in Trichoplusia ni insect cells. The enzyme is capable of
synthesizing both sLexand sialyl-dimeric-Lexstructures in vitro , from
3'-sialyl-lacNAc and VIM-2 structures, respectively, with only low levels
of fucose transfer observed to neutral or 3'-sulfated acceptors. Studies
using fucosylated NeuAcalpha(2-3)-(Galbeta(1- 4)GlcNAc)3-Me acceptors
demonstrate that FucT-VII is able to synthesize both di-fucosylated and
tri-fucosylated structures from mono- fucosylated precursors, but
preferentially fucosylates the distal GlcNAc within a polylactosamine
chain. Furthermore, the rate of fucosylation of the internal GlcNAc
residues is reduced once fucose has been added to the distal GlcNAc. These
results indicate that FucT-VII is capable of generating complex selectin
ligands, in vitro , however the order of fucose addition to the lactosamine
chain affects the rate of selectin ligand synthesis.
相似文献
13.
Kolombet LV Zhigletsova SK Derbyshev VV Ezhov DV Kosareva NI Bystrova EV 《Prikladnaia biokhimiia i mikrobiologiia》2001,37(1):110-114
A technology was designed for manufacturing a preparation based on Trichoderma viride Pers ex S.F. Gray that strongly suppresses the development of causative agents of certain plant diseases and displays a growth-stimulating activity. Cultivation of the strain in a liquid medium for 18-24 h produced up to 60 g dry biomass per liter nutrient medium. A marketable form created in this work conserves the activity of the mycelial preparation for six months. The preparation is compatible with insecticides (carbofos, vismetrin, talstar, and applaud) and certain fungicides (such as baitan). Tests performed with the liquid form of Mycofungicid (seeds were treated with this preparation at a dose of 20-30 g per metric ton before sowing) showed its high efficiency in protecting cereal crops from plant pathogens. The incidence of plant diseases decreased by 65%, and crop yields increased by 15-20%. 相似文献
14.
Yutao Liu Melanie E. Garrett Michelle F. Dennis Kimberly T. Green VA Mid-Atlantic MIRECC Registry Workgroup Allison E. Ashley-Koch Michael A. Hauser Jean C. Beckham Nathan A. Kimbrel 《PloS one》2015,10(3)
Objective
To examine the association between the 5-HTTLPR polymorphism of the serotonin transporter (SLC6A4) gene, combat exposure, and posttraumatic stress disorder (PTSD) diagnosis and among two samples of combat-exposed veterans.Method
The first sample included 550 non-Hispanic Black (NHB) combat-exposed veterans. The second sample included 555 non-Hispanic White (NHW) combat-exposed veterans. Participants were genotyped for the 5-HTTLPR/rs25531 variants of the SLC6A4 gene. A structured clinical interview was used to diagnose PTSD. Combat and civilian trauma exposure were assessed with validated self-report instruments. Logistic regression was used to test for main effects of 5-HTTLPR on PTSD diagnosis as well as gene x environment (GxE) interactions after adjusting for sex, ancestry proportion scores, civilian trauma exposure, and combat exposure.Results
Within the NHB sample, a significant additive effect was observed for 5-HTTLPR (OR = 1.502, p = .0025), such that the odds of having a current diagnosis of PTSD increased by 1.502 for each additional S’ allele. No evidence for an association between 5-HTTLPR and PTSD was observed in the NHW sample. In addition, no evidence for combat x 5-HTTLPR effects were observed in either sample.Conclusion
The present study suggests that there may be an association between 5-HTTLPR genotype and PTSD diagnosis among NHB veterans; however, no evidence for the hypothesized 5-HTTLPR x combat interaction was found. 相似文献15.
KATALIN É. SZABÓ JUDIT MAKK KEVE TIHAMÉR KISS ALEXANDER EILER ÉVA ÁCS BENCE TÓTH ÁRON KEVE KISS STEFAN BERTILSSON 《Freshwater Biology》2008,53(7):1359-1371
1. An artificial glass substratum was incubated in the River Danube for a period of 28 days in order to detect the sequential colonization of microorganisms.
2. Light and fluorescent microscopy showed that microalgae and the picoalgal fraction on the slides increased rapidly over the first 2 weeks of colonization. Diatoms were numerically the most abundant component of the periphyton and their species richness and diversity increased rapidly in the early phase of colonization whereas diversity subsequently increased moderately.
3. Evenness of the diatom community was initially high, lower in the intermediate phase and again higher later on. Succession involving early, intermediate and late colonizer species was observed. Community composition during the first 5 days of colonization was very different from later stages whereas there were only minor changes subsequently.
4. Molecular community analysis by means of terminal restriction fragment length polymorphism analysis of PCR amplified 16S rRNA and 18S rRNA genes pointed to even larger differences between the composition of samples obtained early and late in the period.
5. The number of 18S rRNA and 16S rRNA terminal restriction fragments (T-RF-s) was variable over the colonization period and the fragment patterns of both the bacterial and eukaryotic portion of the microbial community were variable, with most T-RF-s unique to a single sample, suggesting a wide diversity and dynamic properties of periphytic organisms. 相似文献
2. Light and fluorescent microscopy showed that microalgae and the picoalgal fraction on the slides increased rapidly over the first 2 weeks of colonization. Diatoms were numerically the most abundant component of the periphyton and their species richness and diversity increased rapidly in the early phase of colonization whereas diversity subsequently increased moderately.
3. Evenness of the diatom community was initially high, lower in the intermediate phase and again higher later on. Succession involving early, intermediate and late colonizer species was observed. Community composition during the first 5 days of colonization was very different from later stages whereas there were only minor changes subsequently.
4. Molecular community analysis by means of terminal restriction fragment length polymorphism analysis of PCR amplified 16S rRNA and 18S rRNA genes pointed to even larger differences between the composition of samples obtained early and late in the period.
5. The number of 18S rRNA and 16S rRNA terminal restriction fragments (T-RF-s) was variable over the colonization period and the fragment patterns of both the bacterial and eukaryotic portion of the microbial community were variable, with most T-RF-s unique to a single sample, suggesting a wide diversity and dynamic properties of periphytic organisms. 相似文献
16.
17.
Concerted transpositions of mobile genetic elements coupled with fitness changes in Drosophila melanogaster 总被引:3,自引:0,他引:3
Pasyukova EG; Belyaeva ES; Kogan GL; Kaidanov LZ; Gvozdev VA 《Molecular biology and evolution》1986,3(4):299-312
In an inbred low-activity (LA) strain of Drosophila melanogaster with a low
level of fitness and a complex of inadaptive characters, in situ
hybridization reveals an invariant pattern of distribution of three
copia-like elements (mdg-1, mdg-3, and copia). Rare, spontaneous, multiple
transpositions of mobile elements in the LA strain were shown to be coupled
with a drastic increase of fitness. A changed pattern of various types of
mobile elements was also observed on selecting the LA strain for higher
fitness. High-fitness strains show transpositions of mobile elements to
definite chromosomal sites ("hot spots"). Concerted changes in the location
of three different mobile elements were found to be coupled with an
increase of fitness. The mdg-1 distribution patterns were also examined in
two low-fitness strains independently selected from the high-fitness ones.
Fitness decrease was accompanied by mdg-1 excision from the hot spots of
their location usually detected in the high-fitness strains. The results
suggest the existence of a system of adaptive transpositions of mobile
elements that takes part in fitness control.
相似文献
18.
A. O. Berestetskii O. S. Yuzikhin A. S. Katkova A. V. Dobrodumov D. E. Sivogrivov L. V. Kolombet 《Applied Biochemistry and Microbiology》2010,46(1):75-79
An individual substance (20 mg/l) exhibiting phytotoxic properties, which, on the basis its spectral characteristics, was identified as zinniol, was obtained from the fungus Alternaria cirsinoxia. The nonspecific activity of this phytotoxin, with respect to plants of different families, was demonstrated. The minimum concentration (200 μg/ml) at which zinniol damages creeping thistle leaves and the median inhibition concentration (IC 50) for rat embryonic fibroblasts (264 μg/ml) were determined. 相似文献
19.
Strong coupling of plant and fungal community structure across western Amazonian rainforests 总被引:1,自引:0,他引:1
The Amazon basin harbors a diverse ecological community that has a critical role in the maintenance of the biosphere. Although plant and animal communities have received much attention, basic information is lacking for fungal or prokaryotic communities. This is despite the fact that recent ecological studies have suggested a prominent role for interactions with soil fungi in structuring the diversity and abundance of tropical rainforest trees. In this study, we characterize soil fungal communities across three major tropical forest types in the western Amazon basin (terra firme, seasonally flooded and white sand) using 454 pyrosequencing. Using these data, we examine the relationship between fungal diversity and tree species richness, and between fungal community composition and tree species composition, soil environment and spatial proximity. We find that the fungal community in these ecosystems is diverse, with high degrees of spatial variability related to forest type. We also find strong correlations between α- and β-diversity of soil fungi and trees. Both fungal and plant community β-diversity were also correlated with differences in environmental conditions. The correlation between plant and fungal richness was stronger in fungal lineages known for biotrophic strategies (for example, pathogens, mycorrhizas) compared with a lineage known primarily for saprotrophy (yeasts), suggesting that this coupling is, at least in part, due to direct plant–fungal interactions. These data provide a much-needed look at an understudied dimension of the biota in an important ecosystem and supports the hypothesis that fungal communities are involved in the regulation of tropical tree diversity. 相似文献
20.
Kolombet V. A. Lesnykh V. N. Elistratov A. V. Kolombet E. V. Fedorov M. V. Shnoll S. E. 《Biophysics》2019,64(2):300-308
Biophysics - The universal period-tripling system has been discovered in various astronomical, geophysical, and biological phenomena in the range of periods from 1.64 billion years to 50 years; we... 相似文献