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51.
Darja Barlič Maganja Borut Štrukelj Jože Pungerčar Franc Gubenšek Vito Turk Igor Kregar 《Plant molecular biology》1992,20(2):311-313
A genomic DNA clone encoding an aspartic proteinase inhibitor of potato was isolated from a lambda EMBL3 phage library using the aspartic proteinase inhibitor cDNA as a hybridization probe. The gene has all characteristic sequences normally found in eucaryotic genes. Typical CAAT and TATA box sequences were found in the 5-upstream region. In this part are also two putative regulatory AGGA box sequences located. In the genomic sequence there are no intron sequences interrupting the coding region. An open reading frame of the gene encodes a precursor protein of 217 amino acids which shows high percent identity with the aspartic proteinase inhibitor cDNA. 相似文献
52.
Ptáková Michaela Pokorný Petr Šída Petr Novák Jan Horáček Ivan Juřičková Lucie Meduna Petr Bezděk Aleš Myšková Eva Walls Matthew Poschlod Peter 《Vegetation History and Archaeobotany》2021,30(2):269-286
Vegetation History and Archaeobotany - In a continuous, perfectly stratified sedimentary sequence which was discovered under a large sandstone overhang in northern Bohemia, Czech Republic, we... 相似文献
53.
High abundance of cockspur (Echinochloa crus-galli) at the geothermal carbon dioxide spring area in Staveinci indicates that this species is able to grow under widely varying CO2 concentrations. Living cockspur plants can even be found very close to gas-releasing vents where growth is significantly reduced. Plant height correlated well with CO2 exposure. The 13C value of the CO2 spring air was –3.9 and 13C values of high-, medium-, and low-CO2 plants were –10.14, –10.44, and –11.95 , respectively. Stomatal response directly followed the prevailing CO2 concentrations, with the highest reduction of stomatal conductance in high CO2 concentration grown plants. Analysis of the curves relating net photosynthetic rate to intercellular CO2 concentration (P
N-Ci curves) revealed higher CO2 compensation concentration in plants growing at higher CO2 concentration. This indicates adjustment of respiration and photosynthetic carbon assimilation according to the prevailing CO2 concentrations during germination and growth. There was no difference in other photosynthetic parameters measured. 相似文献
54.
In 1865, the German botanist Julius Sachs published a seminal monograph entitled Experimental-Physiologie der Pflanzen (Experimental Physiology of Plants) and hence became the founder of a new scientific discipline that originated 150 y ago. Here, we outline the significance of the achievements of Sachs. In addition, we document, with reference to his Vorlesungen über Pflanzen-Physiologie (Lectures on the Physiology of Plants, 1882), that Sachs was one of the first experimentalists who proposed the functional unity of all organisms alive today (humans, animals, plants and other “vegetable” organisms, such as algae, cyanophyceae, fungi, myxomycetes, and bacteria). 相似文献
55.
J. Bubeník J. Ježek M. Zaoral J. Hofmann Y. V. Gruntenko J. G. Osipov A. G. Zolotareva T. E. Vakhrusheva V. G. Budker 《Cancer immunology, immunotherapy : CII》1984,18(2):123-125
Summary Treatment with synthetic MDP inhibited growth of transplantable, chemically induced tumors in syngeneic mice. The tumor-inhibitory effect was dependent on the schedule of MDP administration.Growth of SC transplants of a nonmetastasizing, MC-induced fibrosarcoma, MC11, was inhibited by local treatment with 200 g and 1,000 g MDP given SC 5–7 weeks before challenge. Treatment with lower (10 g and 100 g) doses of MDP and shorter (1–4 weeks) time intervals was not effective. Single doses of MDP (10–1,000 g) 1–3 weeks after challenge had no effect.Growth of IV-inoculated, metastasizing AAT-induced hepatoma A was inhibited by IV injections of 20 g MDP given 1 and 2 days prior to the challenge. Significant increases in the survival of hepatoma-bearing mice were observed only after injections of MDP incorporated in multilamellar liposomes.Abbreviations MDP
n-acetylmuramyl-l-alanyl-d-isoglutamine
- B10
C57BL/10ScSnPh mice
- MC
3-methylcholanthrene
- ATT
o-amino-azotoluene
- PBS
phosphate-buffered saline 相似文献
56.
The entire double-stranded DNA genome of the Streptomyces aureofaciens phage mu1/6 was sequenced and analyzed. Its size is 38.194 kbp with an overall molar G+C content of 71.2 %. Fifty-two potential open reading frames (orfs) were identified, divided into two oppositely transcribed regions. In the left arm of the mu1/6 genome, an identified putative integrase and possible regulation proteins were identified. The rightwards transcribed region contains genes organized into apparently four functional units responsible for: (i) replication, (ii) DNA packaging and head assembly, (iii) tail morphogenesis, and (iv) lysis. Putative functions were assigned to twelve orfs based on bioinformatic analysis or experimental substantiation. Comparative analysis with three complete genomes of streptomycete phages revealed resemblance with respect to the organization of their genes into functional modules. Closer relationship was observed only between mu1/6 and S. venezuelae phage VWB. 相似文献
57.
Halil Erhan Eroğlu Neslihan Şimşek Murat Koç Ergin Hamzaoğlu 《Plant Systematics and Evolution》2013,299(1):67-73
Karyotypic characters, mitotic metaphase chromosomes, monoploid idiograms and karyograms of Minuartia anatolica (Boiss.) Woronow var. phrygia (Bornm.) McNeill, Minuartia anatolica (Boiss.) Woronow var. scleranthoides (Boiss. & Noe) McNeill, Minuartia corymbulosa (Boiss. & Balansa) McNeill var. gypsophilloides McNeill and Minuartia aksoyi M.Koç & Hamzao?lu were investigated for the first time. Analysis of somatic metaphases showed that the chromosome numbers and the formulas of these taxa were 2n = 24 = 14m + 6sm + 4st for Minuartia anatolica var. phrygia, 2n = 14 = 6m + 8sm for Minuartia anatolica var. scleranthoides, 2n = 14 = 6m + 4sm + 4st for Minuartia corymbulosa var. gypsophilloides and 2n = 30 = 14m + 10sm + 6st for Minuartia aksoyi. No satellites were observed in the karyotypes of these taxa. Karyotype asymmetry was estimated by many different methods, namely the Stebbins classification, the karyotype asymmetry index (As K %), the total form percent (TF %), the Rec and Syi indices, the intrachromosomal asymmetry index (A1) and interchromosomal asymmetry index (A2), the dispersion index (DI), the degree of asymmetry of karyotype (A index) and the asymmetry index (AI). 相似文献
58.
Filip Kolá? Milan ?tech Pavel Trávní?ek Jana Rauchová Tomá? Urfus Petr Vít Magdalena Kube?ová Jan Suda 《Annals of botany》2009,103(6):963-974
Background and Aims
Detailed knowledge of variations in ploidy levels and their geographic distributions is one of the key tasks faced in polyploid research in natural systems. Flow cytometry has greatly facilitated the field of cytogeography by allowing characterization of ploidy levels at both the regional and population scale, and at multiple stages of the life cycle. In the present study, flow cytometry was employed to investigate the patterns and dynamics of ploidy variation in the taxonomically challenging complex Knautia arvensis (Dipsacaceae) and some of its allies (K. dipsacifolia, K. slovaca) in Central Europe.Methods
DNA ploidy levels were estimated by DAPI flow cytometry in 5205 adult plants, 228 seedlings and 400 seeds collected from 292 Knautia populations in seven European countries. The flow cytometric data were supplemented with conventional chromosome counts. A subset of 79 accessions was subjected to estimation of the absolute genome size using propidium iodide flow cytometry.Key Results and Conclusions
Five different ploidy levels (from 2x to 6x) were found, with triploids of K. arvensis being recorded for the first time. The species also exhibited variation in the monoploid genome size, corresponding to the types of habitats occupied (grassland diploid populations had larger genome sizes than relict and subalpine diploid populations). Disregarding relict populations, the distribution of 2x and 4x cytotypes was largely parapatric, with a diffuse secondary contact zone running along the north-west margin of the Pannonian basin. Spatial segregation of the cytotypes was also observed on regional and microgeographic scales. The newly detected sympatric growth of diploids and tetraploids in isolated relict habitats most likely represents the primary zone of cytotype contact. Ploidy level was found to be a major determinant of the strength of inter-cytotype reproductive barriers. While mixed 2x + 4x populations virtually lacked the intermediate ploidy level at any ontogenetic stage, pentaploid hybrids were common in 4x +6x populations, despite the cytotypes representing different taxonomic entities.Key words: Contact zone, cytogeography, flow cytometry, genome size, hybridization, Knautia arvensis, ploidy mixture, polyploidy, relict, reproductive isolation, serpentine 相似文献59.
Ivana Šagud Nikolina Maček Hrvat Ana Grgičević Tena Čadež Josipa Hodak Milena Dragojević 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):460-467
Abstract The enzymes acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are primary targets in attenuating the symptoms of neurodegenerative diseases. Their inhibition results in elevated concentrations of the neurotransmitter acetylcholine which supports communication among nerve cells. It was previously shown for trans-4/5-arylethenyloxazole compounds to have moderate AChE and BChE inhibitory properties. A preliminary docking study showed that elongating oxazole molecules and adding a new NH group could make them more prone to bind to the active site of both enzymes. Therefore, new trans-amino-4-/5-arylethenyl-oxazoles were designed and synthesised by the Buchwald-Hartwig amination of a previously synthesised trans-chloro-arylethenyloxazole derivative. Additionally, naphthoxazole benzylamine photoproducts were obtained by efficient photochemical electrocyclization reaction. Novel compounds were tested as inhibitors of both AChE and BChE. All of the compounds exhibited binding preference for BChE over AChE, especially for trans-amino-4-/5-arylethenyl-oxazole derivatives which inhibited BChE potently (IC50 in µM range) and AChE poorly (IC50?100?µM). Therefore, due to the selectivity of all of the tested compounds for binding to BChE, these compounds could be applied for further development of cholinesterase selective inhibitors.
- HIGHLIGHTS
-
Series of oxazole benzylamines were designed and synthesised
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The tested compounds showed binding selectivity for BChE
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Naphthoxazoles were more potent AChE inhibitors
60.