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The effects of two elicitors: jasmonic acid and methyl jasmonate on cell growth as well as on rosmarinic acid accumulation in cell suspension cultures of Mentha × piperita were investigated. The highest rosmarinic acid accumulation 117.95 mg g−1 DW (12% DW) was measured 24 h after addition of 100 μM methyl jasmonate. A similar concentration 110.12 mg g−1 DW was detected 48 h after application of 200 μM jasmonic acid. Those values were nearly 1.5 times higher compared to the control sample, without elicitation. There was no substantial influence of elicitors on rosmarinic acid secretion into the culture media. Extracellular concentrations of rosmarinic acid were similar to the values from the control variants. It was documented that suspension cultures of M. piperita treated with elicitors showed a decrease in biomass accumulation when compared to the control.  相似文献   

4.
We analysed the influence of contemporary geography on butterfly diversity for islands in the Mediterranean Basin. We found that island size and distance from the mainland has a significant effect on the number of species. We also used butterflies as an indicator group to identify the importance of forest habitats for biodiversity conservation in the island of Cyprus. To understand the relative importance of local vegetation characteristics of butterflies in the Pentadaktylos mountains transect counts were used to assess the abundance and butterfly diversity in two different forest types. A total of 1,602 butterflies and 23 species were recorded during this research. We observed highly significant effects of forest type on abundance and species richness of butterflies. For example, number of butterflies was significantly higher in old forest than young pine forest. Also, the abundance of endemic butterflies was highest in old forest habitats. Therefore, the survival of the majority of endemic butterflies in Cyprus may depend on conservation of old forests and their understorey plants.  相似文献   

5.
The binding of the reductase inhibitor drug fluvastatin, hydroxy-3-methylglutaryl coenzyme A, with the hydrophilic ι- or λ-carrageenan polymers, serving as potential controllers of the drug’s release rate, have been studied at the density functional level of theory with the B3LYP exchange correlation functional. Three low energy conformers of fluvastatin have been calculated. The vibrational spectroscopic properties calculated for the most stable conformer were in satisfactory agreement with the experimental data. A series of hydrogen bonded complexes of the most stable conformer of fluvastatin anion with low molecular weight models of the polymers have been fully optimized. In almost all, intermolecular H-bonds are formed between the sulfate groups of ι- or λ-carrageenan and fluvastatin’s hydroxyls, resulting in a red shift of the fluvastatin’s O − H stretching vibrations. Cooperative intramolecular H-bonds within fluvastatin or ι-, λ-carrageenan are also present. The BSSE and ZPE corrected interaction energies were estimated in the range 281–318 kJ mol−1 for ι-carrageenan - fluvastatin and 145–200 kJ mol−1 for λ-carrageenan - fluvastatin complexes. The electron density (ρ bcp) and Laplacian (∇2 ρ bcp) properties at critical points of the intermolecular hydrogen bonds, estimated by AIM (atoms in molecules) calculations, have a low and positive character (∇2 ρ bcp > 0), consistent with the electrostatic character of the hydrogen bonds. The structural and energetic data observed, as well as the extent of the red shift of the fluvastatin’s O − H stretching vibrations upon complex formation and the properties of electron density show a stronger binding of fluvastatin to ι- than to λ-carrageenan.  相似文献   

6.
Scyphozoan medusae are very successful foragers which occasionally occur in high abundances in boreal waters and may impact many different groups in the marine ecosystem by means of a variety of toxins. A rainbow trout gill cell line, RTgill-W1, was tested for its suitability as quantitative indicator of the cytotoxicity of Cyanea capillata and Aurelia aurita; the major scyphozoan species in the North and Baltic seas. Cultures of rainbow trout gill cells were exposed to whole venoms extracted from fishing tentacles and oral arms at increasing protein concentrations. The venom caused detachment, clumping and lysis of cells, as well as a drop in vitality, in a dose-dependent manner. Morphological changes in the cells were evident within 1 h after venom addition. The damage to gill cells was quantified by measuring the metabolic activity of the cells by means of the fluorescence of resorufin derived from the nonfluorescent substrate, resazurin. In general, a decrease in the metabolic activity of the cells was detected at a venom (protein) concentration above 2.0 μg ml−1 (corresponding to 0.2 μg 104 cells−1), and a total loss of activity was observed above 40.0 μg ml−1 (corresponding to 4.0 μg 104 cells−1). C. capillata venoms had increased cytotoxic activity as compared to A. aurita venoms at the same concentration. Cnidocyst extracts from oral arms of A. aurita induced an 85% loss of gill cell viability at concentrations of 0.2 μg 104 cells−1, whereas crude venoms from fishing tentacles reduced cell viability by 18% at the same concentration. Gel electrophoresis of the venoms indicated that these consist of a large number of proteins in a fairly wide size range, from 6 to 200 kDa, including some that are the same size as those found in cubomedusae. It also appears that larger (i.e., older) medusae have more complex venoms and, in some cases, more potent venoms than smaller animals.  相似文献   

7.
We undertook a field study to determine whether comb cell size affects the reproductive behavior of Varroa destructor under natural conditions. We examined the effect of brood cell width on the reproductive behavior of V. destructor in honey bee colonies, under natural conditions. Drone and worker brood combs were sampled from 11 colonies of Apis mellifera. A Pearson correlation test and a Tukey test were used to determine whether mite reproduction rate varied with brood cell width. Generalized additive model analysis showed that infestation rate increased positively and linearly with the width of worker and drone cells. The reproduction rate for viable mother mites was 0.96 viable female descendants per original invading female. No significant correlation was observed between brood cell width and number of offspring of V. destructor. Infertile mother mites were more frequent in narrower brood cells.  相似文献   

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To study the production of secondary metabolites of Maesa lanceolata and Medicago truncatula, hairy root cultures of both plant species were established. Because maintenance of large numbers of cultures is laborious and costly, we developed a cryopreservation protocol and stored different isolated lines over time. Using encapsulation-dehydration, high survival rates were observed for both Maesa and Medicago hairy roots. Root tips were isolated and encapsulated in calcium-alginate beads, containing 0.1 M sucrose. The encapsulated hairy roots were precultured for 3 days using basal medium containing high sucrose concentrations. Medicago root tip growth during the preculturing time lead to unwanted outgrowth which could be tempered by addition of plant growth inhibitors. After preculturing, the beads were dehydrated in the air flow of a laminar flow until 35–40% of the initial bead weight was reached. Dehydrated beads were plunged into liquid nitrogen and after different storage times thawed in a water bath at 40°C. The survival rates were 90% for Maesa and 53% for Medicago, which are sufficient to allow implementation in large storage experimental set-ups.  相似文献   

10.
Summary.  2H-Pyran-2-ones 1 were transformed with various hydrazines into (E)- or (Z)-α,β-didehydro-α-amino acid (DDAA) derivatives 4 (and 7) containing a highly substituted pyrazolyl moiety attached at the β-position. With heterocyclic hydrazines, the products 4 were accompanied also by decarboxylated enamines E-6. In order to separate (E/Z)-mixtures of acids, they were transformed to the corresponding methyl esters 9 and 10 by the application of diazomethane. Catalytic hydrogenation under high pressures with Pd/C as a catalyst resulted in the formation of racemic alanine derivatives 11. Received January 29, 2002 Accepted May 27, 2002 Published online December 18, 2002 RID="*" ID="*"  Dedicated with deep respect to Professor Waldemar Adam on the occasion of his 65th birthday. Acknowledgements We thank the Ministry of Education, Science and Sport of the Republic of Slovenia for the financial support (P0-0503-103). Dr. B. Kralj and Dr. D. Žigon (Center for Mass Spectroscopy, “Jožef Stefan” Institute, Ljubljana, Slovenia) are gratefully acknowledged for the mass measurements. Authors' address: Prof. Marijan Kočevar, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, SI-1000 Ljubljana, Slovenia, E-mail: marijan.kocevar@uni-lj.si  相似文献   

11.
The Brassica napus 60K Illumina Infinium? SNP array has had huge international uptake in the rapeseed community due to the revolutionary speed of acquisition and ease of analysis of this high-throughput genotyping data, particularly when coupled with the newly available reference genome sequence. However, further utilization of this valuable resource can be optimized by better understanding the promises and pitfalls of SNP arrays. We outline how best to analyze Brassica SNP marker array data for diverse applications, including linkage and association mapping, genetic diversity and genomic introgression studies. We present data on which SNPs are locus-specific in winter, semi-winter and spring B. napus germplasm pools, rather than amplifying both an A-genome and a C-genome locus or multiple loci. Common issues that arise when analyzing array data will be discussed, particularly those unique to SNP markers and how to deal with these for practical applications in Brassica breeding applications.  相似文献   

12.
Different lines of cell suspension cultures of Taxus × media Rehd. and Taxus floridana Nutt. were cryopreserved with a two-step freezing method using a simple and inexpensive freezing container instead of a programmable freezer. Four to seven days old suspension cell cultures were precultured in growth medium supplemented with 0.5 M mannitol for 2 d. The medium was then replaced with cryoprotectant solution (1 M sucrose, 0.5 M glycerol and 0.5 M dimethylsulfoxide) and the cells incubated on ice for 1 h. Before being plunged into liquid nitrogen, cells were frozen with a cooling rate of approximately −1 °C per min to −80 °C. The highest post-thaw cell viability was 90 %. The recovery was line dependent. The cryopreservation procedure did not alter the nuclear DNA content of the cell lines. The results indicate that cryopreservation of Taxus cell suspension cultures using inexpensive freezing container is possible.  相似文献   

13.
Gamma-fluorinated analogues of glutamic acid and glutamine are compounds of biological interest. Syntheses of such compounds are extensively reviewed in this article. 4-fluoroglutamic acid was prepared as a mixture of racemic diastereomers by Michael reaction, inverse-Michael reaction or by electrophilic / nucleophilic fluorination. Optically enriched 4-fluoroglutamic acids were obtained by several resolution techniques as well as by asymmetric methodologies using the chiral pool. 4-fluoroglutamine was prepared as a mixture of stereoisomers as well as in racemic erythro and threo forms from the corresponding 4-fluoroglutamic acids using aminolysis and conventional protection and deprotection strategies. Racemic 4,4-difluoroglutamic acid was synthesized by a nitroaldol reaction and its L-enantiomer obtained via three different asymmetric routes. Racemic 4,4-difluoroglutamic acid was converted into the corresponding 4,4-difluoroglutamine using a protection / aminolysis / deprotection sequence while N-Boc-L-4,4-difluoroglutamine was prepared directly from (R)-Garner's aldehyde using a Reformatsky reaction as the key step.  相似文献   

14.
Recombinant Zantedeschia aethiopica agglutinin (ZAA) was expressed in Escherichia coli as N-terminal His-tagged fusion. After induction with isopropylthio-β-d-galactoside (IPTG), the recombinant ZAA was purified by metal-affinity chromatography. The purified ZAA protein was applied in anti-fungal assay and the result showed that recombinant ZAA had anti-fungal activity towards leaf mold (Fulvia fulva), one of the most serious phytopathogenic fungi causing significant yield loss of crops. This study suggests that ZAA could be an effective candidate in genetic engineering of plants for the control of leaf mold.  相似文献   

15.
Dana Bernátová 《Biologia》2008,63(2):175-176
The paper brings information on an isolated occurrence and morphological characters of Carex × involuta and C. juncella populations in the Vel’ká Fatra Mts. Their presence has been known neither from the territory of Slovakia nor from the whole Western Carpathians till now.  相似文献   

16.
The lipase Lip2 of the edible basidiomycete, Pleurotus sapidus, is an extracellular enzyme capable of hydrolysing xanthophyll esters with high efficiency. The gene encoding Lip2 was expressed in Escherichia coli TOP10 using the gene III signal sequence to accumulate proteins in the periplasmatic space. The heterologous expression under control of the araBAD promoter led to the high level production of recombinant protein, mainly as inclusion bodies, but partially in a soluble and active form. A fusion with a C-terminal His tag was used for purification and immunochemical detection of the target protein. This is the first example of a heterologous expression and periplasmatic accumulation of a catalytically active lipase from a basidiomycete fungus.  相似文献   

17.
Survey of seven strains determined as Septonema ochraceum (Dothideomycetes, inc. sed.) isolated from pine litter or obtained from public collections revealed three new species, Fusicladium cordae, F. sicilianum (Venturiaceae), Cladophialophora matsushimae (Herpotrichiellaceae) and a cryptic species morphologically identical to Devriesia americana (Teratosphaeriaceae), but phylogenetically distinct. Morphological survey and phylogenetic analysis using nucleotide sequence data from the nuclear ribosomal subunit genes indicate a close relationship within three species colonising pine litter needles, F. cordae, F. pini and F. ramoconidii. F. sicilianum is most related to F. rhodense. C. matsushimae represents a species belonging to one of the lineages of the polyphyletic genus Cladophialophora. None of the strains observed can be classified morphologically as S. ochraceum, of which the type material does not exist.  相似文献   

18.
Resistance to fatal disease bovine spongiform encephalopathy (BSE), due to misfolded prion protein in cattle, is associated with a 23-bp indel polymorphism in the putative promoter and a 12-bp indel in intron 1 of the PRNP gene. Gayal (Bos frontalis) is an important semiwild bovid species and of great conservation concern, but till today these indel polymorphisms have not been evaluated in gayals. Therefore, we collected 225 samples of gayals and evaluated the genetic indel polymorphism in the two regions of this PRNP gene. The results revealed high allelic frequencies of insertions at these indel sites: 0.909 and 0.667 for, respectively, the 23 bp and 12 bp indels, both also with significant genotype frequencies (\(\chi ^{2}\): 9.81; 23 bp and \(\chi ^{2}\): 43.56; 12 bp). At the same time, the haplotype data showed indel polymorphisms with extremely low deletion (0.01) in both regions of the PRNP gene. We compared these data with those reported for healthy and BSE-affected cattle (Bos taurus) breeds from two European countries, Germany and Switzerland, and significant difference (\(P\,{<}\,0.001\)) was observed between BSE-affected as well as the healthy cattle. Further, our data were also extensively compared with previous reports on BSE and highly significant (\(P\,{<}\,0.001\)) outcomes were observed. This result suggested negligible genetic susceptibility to BSE in gayals. To the best of our knowledge, this study is the first comprehensive deciphering information about the PRNP indel polymorphisms of 23 bp and 12 bp in gayals, a semiwild species of China.  相似文献   

19.
Functional expression of heterologous Pseudozyma antarctica lipase B (PalB) in the periplasm of Escherichia coli was explored using four fusion tags, i.e. DsbC, DsbA, maltose-binding protein (MBP), and FLAG in the sequence of increasing expression efficacy. Amongst these fusion tags, FLAG and MBP appear to be the most effective ones in terms of boosting enzyme activity and enhancing solubility of PalB, respectively. Overexpression of these PalB fusions often resulted in concomitant formation of insoluble inclusion bodies. Coexpression of a selection of periplasmic folding factors, including DegP (and its mutant variant of DegPS210A), FkpA, DsbA, DsbC, and a cocktail of SurA, FkpA, DsbA, and DsbC, could improve the expression performance. Coexpression of DsbA appeared to be the most effective in reducing the formation of inclusion bodies for all the four PalB fusions, implying that functional expression of PalB could be limited by initial bridging of disulfide bonds. Culture performance was optimized by overexpressing FLAG-PalB with DsbA coexpression, resulting in a high volumetric PalB activity of 360 U/L.  相似文献   

20.
Much attention has been focused on the study of lactoferrin at the protein or nucleotide level in mice, humans, and cattle, but little is known about it in goats. The goat LF gene from 5' UTR to exon 17 was amplified, and the variation of g.7605C→T in 10 Chinese indigenous goat breeds was analyzed. Among the three ruminant species (cattle, sheep, and goats), the intron-exon distribution pattern was similar, and all the exons had the same length, but the length of introns varied greatly due to insertions or deletions. The frequency of allele T at g.7605C→T (50.12%) was a little higher than that of allele C (49.88%), and the genotype distribution differed greatly between goat populations. The g.7605C→T site showed higher genetic diversity in goat populations. The genetic differentiation was 0.0783, and gene flow was 2.9433 among the 10 Chinese indigenous goat populations.  相似文献   

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