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1.
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   

2.
The stored-product mites are the most abundant and frequent group of pests living on the stored food products in Europe. They endanger public health since they produce allergens and transmit mycotoxin-producing fungi. Novel acaricidal compounds with inhibitory effects on the digestive enzymes of arthropods are a safe alternative to the traditional neurotoxic pesticides used for control of the stored-product pests. In this work, we explored the properties of acarbose, the low molecular weight inhibitor of -amylases (AI), as a novel acaricide candidate for protection of the stored products from infestation by Acarus siro (Acari: Acaridae). In vitro analysis revealed that AI blocked efficiently the enzymatic activity of digestive amylases of A. siro, and decreased the physiological capacity of mites gut in utilizing a starch component of grain flour. In vivo experiments showed that AI suppressed the population growth of A. siro. The mites were kept for three weeks on experimental diet enriched by AI in concentration range of 0.005 to 0.25%. Population growth of A. siro was negatively correlated with the content of AI in the treated diet with a half-population dose of 0.125%. The suppressive effect of AIs on stored-product mites is discussed in the context of their potential application in GMO crops  相似文献   

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λ DNA stimulates a low level of protein synthesis in extracts of E. coli supplemented with RNA polymerase. The synthesis is efficiently and specifically repressed by addition of purified λ repressor. About 90% of the protein product is from the rightwards, or tof, promoter (P R ) and 10% from the leftwards, or N, promoter (P L ). The main polypeptide product is a low molecular species from the tof operon.  相似文献   

6.
Malaysia is fortunate and proud to contain some of the world’s richest biodiversity. In Malaysia, there are an estimated 185,000 species of fauna and 12,500 species of flowering plants, many of which are endemic to tropical forests in this region. Indeed, such diversity is an important and invaluable national asset to safeguard both present and future generations. In vitro conservation offers possible techniques for the preservation of plant germplasm that at present is difficult to maintain or is maintained with limited success. Research at the Universiti Kebangsaan Malaysia (The National University of Malaysia) focuses on the cryopreservation of woody fruit species with seeds that cannot tolerate cryopreservation (recalcitrant or intermediate). Among the plants with recalcitrant seeds are such traditionally important edible tropical fruits as mangosteen, langsat, and rambai (Garcinia mangostana, Lansium domesticum, and Baccaurea motleyana). Citrus aurantifolia, Citrus suhuiensis, Citrus madurensis, Citrus hystrix, and Fortunella polyandra are among the Citrus and Citrus-related species studied. Cryopreservation studies include the Nepenthes species (pitcher plants) of Malaysia. Fundamental research on desiccation and low-temperature tolerance and on the physiology of desiccation are used to understand seed behavior, a prerequisite for the development of successful conservation techniques. At the same time, cryopreservation protocols for several Citrus and forestry species were developed for embryonic axes and adventitious shoots, mainly using rapid dehydration and PVS2 vitrification techniques. There are no successful standard techniques or protocols for species with highly recalcitrant seeds such as Garcinia species. Modification of existing protocols or development of new methods is required, but this can be accomplished only when a detailed understanding of the recalcitrant nature of the seeds or explants is achieved. While we have considerable knowledge concerning the basics of biochemical processes and some molecular data from work on desiccation-tolerant seeds, a great need remains for understanding the cause of the recalcitrance or desiccation sensitivity of these seeds. It may be necessary to use a systems biology approach that exploits the “omics” technologies to generate global molecular data. In combination with bioinformatics for data integration and analyses, this approach would move toward improved modeling of the biological pathways associated with the development of recalcitrant seeds.  相似文献   

7.
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   

8.

Background  

The presence of β-lactamases in Y. enterocolitica has been reported to vary with serovars, biovars and geographical origin of the isolates. An understanding of the β-lactamases in other related species is important for an overall perception of antibiotic resistance in yersiniae. The objective of this work was to study the characteristics of β-lactamases and their genes in strains of Y. intermedia and Y. frederiksenii, isolated from clinical and non-clinical sources in India.  相似文献   

9.
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   

10.
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   

11.
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   

12.
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   

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THE moulting hormone of insects is sometimes referred to as a growth and differentiation hormone. The steroid ecdysone and ecdysone analogues were shown to promote differentiation both in vivo and in vitro1–3 but their action on cell multiplication is not certain4–10. I used a diploid cell line, established from Drosophila melanogaster embryos by Echalier and Ohanessian11,12, to assay insect hormones.  相似文献   

15.
Specific activities and isoform patterns of peroxidases, acid phosphatases, DNases and RNases were studied in relation to in vitro rooting of Petunia × hybrida microshoots in the presence of 4 μM indole-3-butyric acid (IBA). Specific activities of the above enzymes increased in the course of rooting. Rhizogenesis could be related with an increased specific activity of peroxidases during the initiation phase, in parallel with increased lignin content. Twelve peroxidases, six anionic (A1–A6) and six cationic (C1–C6), seven acid phosphatases (ACP1–ACP7), seven RNases (R1–R7) and four DNases (D1–D4) isoforms were detected following native PAGE. Variation in the number of the above isoforms and their quantity was observed during different stages of rooting. Particularly, A2, A3, C3, C4, C5, ACP2, R1, R2, R3, and D4 isoforms appeared after the induction phase and could be related to emergence of root primordia. Additionally, R3 and D4 could be associated with cell division and differentiation, since these are only expressed in rooted microshoots. Moreover, the higher number of roots in IBA-treated microshoots could be related to the higher expression of RNase and DNase isoforms during initiation and expression phases.  相似文献   

16.
Three cassava clones (SOM-1, “05”, and “50”) were cultured in vitro on MS medium plus sucrose (30 g L−1) and myo-inositol (100 mg L−1) without plant growth regulators and with additions of 0 (control), 0.5, 1, 1.5, 2, 2.5, and 3 g L−1 NaCl to test their salt tolerance. The same cassava clones were cultivated in greenhouse conditions on a sandy soil substratum and irrigated with 20% strength Hoagland solution, and additions of 0, 4, and 8 g L−1 of NaCl. Salinity negatively affected the survival, development, leaf water content, and mineral composition (mainly by accumulation of Cl and Na) of both in vitro and ex vitro plants, but with different intensity in each clone. In both conditions of culture (in vitro and ex vitro) clone SOM-1, from a desert arid saline zone of Somalia, was the most tolerant and clone “05”, from a rainy region of Ivory Coast, the most sensitive. Clone “50” tolerance to in vitro salt treatments, although lower, was not significantly different from that of SOM-1 but the ex vitro response was similar to “05”. In general, there was a correlation between in vitro and ex vitro behavior of the cassava plant regarding salt tolerance, which would allow the in vitro culture method to be used for selection of salt-tolerant plants of this crop.  相似文献   

17.
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   

18.
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   

19.
There are presently many methods of detecting complex carbohydrates, and particularly glycogen. However most of them require radioisotopes or destruction of the tissue and hydrolysis of glycogen to glucose. Here we present a new method based on the incorporation of 2-NBDG (2-{N-[7-nitrobenz-2-oxa-1, 3-diazol 4-yl] amino}-2-deoxyglucose), a D-glucose fluorescent derivative, into glycogen. Two kinds of approaches were carried out by using Clone 9 rat hepatocytes as a cellular model; (1) Incubation of cell lysates with 2-NBDG, carbohydrate precipitation in filters and measurement of fluorescence in a microplate reader (2) Incubation of living hepatocytes with 2-NBDG and recording of fluorescence images by confocal microscopy. 2-NBDG labeled glycogen in both approaches. We confirmed this fact by comparison to the labeling obtained with a specific monoclonal anti-glycogen antibody. Also drugs that trigger glycogen synthesis or degradation induced an increase or decrease of fluorescence, respectively. This is a simple but efficient method of detecting glycogen with 2-NBDG. It could be used to record changes in glycogen stores in living cells and cell-free systems and opens the prospect of understanding the role of this important energy reserve under various physiological and pathophysiological conditions.  相似文献   

20.
Explants obtained from in vitro-propagated plantlets of two potato cultivars, Shepody and Atlantic, were treated with five doses of γ-radiation (0, 2, 4, 6 and 8 Gy) to investigate the stimulating effects of low irradiation on the production and quality of microtubers in vitro. Microtubers of both cultivars treated with γ-radiation initiated 5 d earlier than in the non-irradiated control. The whole period of microtuberization was prolonged by 10 – 15 d with 4, 6 and 8 Gy irradiation treatment for cv. Atlantic. Irradiation of the plantlets (4 Gy) led to a significant increase not only in the microtuber number (116.7 and 34.5 % over the control) but also in the fresh mass (77.6 and 23.2 % in Shepody and Atlantic, respectively). Low dose irradiation (2 – 4 Gy) increased the starch content of microtubers. High doses (6 – 8 Gy) enhanced ascorbic acid and reducing sugar contents. 4 – 6 Gy doses also effectively increased the protein contents of microtubers.  相似文献   

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