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1.
The biochemical mechanism underlying the development of fruiting bodies in Flammulina velutipes, an edible mushroom, was investigated using the YBLB colorimetric assay to distinguish between the normal strain (FVN-1) and the degenerate strain (FVD-1). In this assay, the color of the YBLB medium (blue-green) inoculated with FVN-1 exhibiting normal fruiting body development changed to yellow, while the color of the medium inoculated with FVD-1 changed to blue. In this study, we found that this color difference originated from extracellular laccase produced by FVN-1. Moreover, FVN-1 exhibited considerably higher extracellular laccase activity than FVD-1, under conditions facilitating fruiting body formation. Overall, these findings suggest that extracellular laccase is involved in the fruiting body development process in F. velutipes.  相似文献   

2.
A new yellow carotenoid, named 5,6-dihydrocrustaxanthin (6), was isolated together with five yellow xanthophylls: isoastaxanthin (1), 5,6-dihydropenaeusxanthin (2), penaeusxanthin (3), tetrahydroxypirardixanthin (4), and crustaxanthin (5) from three species of prawns: Marsupenaeus japonicus, Litopenaeus vannamei, and Metapenaeus joyneri, belonging to Penaeidae. The structure of (6) was determined to be (3R,4S,5R,6R,3′R,4′S)-5,6-dihydro-β,β-carotene-3,4,3′,4′-tetrol by UV-VIS, MS, 1H NMR, and CD spectral data. Distributions of yellow xanthophylls (16) in ten species of shrimps were investigated from a chemo-systematic point of view. Yellow xanthophylls (16) were present in only three species of prawns described above, among the ten species of shrimps investigated. Instead of 16, luteins and tunxanthins, having the 3-hydroxy-ε-end group, were present in other species of shrimps belonging to Penaeidae, Pandalidae, and Palaemonidae.  相似文献   

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Key message

Genetic modulation of the carotenogenesis in I. germanica ‘Fire Bride’ by ectopic expression of a crtB gene causes several flower parts to develop novel orange and pink colors.

Abstract

Flower color in tall bearded irises (Iris germanica L.) is determined by two distinct biochemical pathways; the carotenoid pathway, which imparts yellow, orange and pink hues and the anthocyanin pathway, which produces blue, violet and maroon flowers. Red-flowered I. germanica do not exist in nature and conventional breeding methods have thus far failed to produce them. With a goal of developing iris cultivars with red flowers, we transformed a pink iris I. germanica, ‘Fire Bride’, with a bacterial phytoene synthase gene (crtB) from Pantoea agglomerans under the control of the promoter region of a gene for capsanthin–capsorubin synthase from Lilium lancifolium (Llccs). This approach aimed to increase the flux of metabolites into the carotenoid biosynthetic pathway and lead to elevated levels of lycopene and darker pink or red flowers. Iris callus tissue ectopically expressing the crtB gene exhibited a color change from yellow to pink-orange and red, due to accumulation of lycopene. Transgenic iris plants, regenerated from the crtB-transgenic calli, showed prominent color changes in the ovaries (green to orange), flower stalk (green to orange), and anthers (white to pink), while the standards and falls showed no significant differences in color when compared to control plants. HPLC and UHPLC analysis confirmed that the color changes were primarily due to the accumulation of lycopene. In this study, we showed that ectopic expression of a crtB can be used to successfully alter the color of certain flower parts in I. germanica ‘Fire Bride’ and produce new flower traits.  相似文献   

5.
Modification of two assay procedures (Van Belle, H. (1970) Anal. Biochem.33, 132–142 and Itaya, K., and Ui, M. (1966) Clin. Chim. Acta14, 361) has allowed the development of a manual assay for inorganic phosphate of high simplicity and sensitivity. Total analysis requires only three reagents and is accomplished in less than 5 min, and smaples containing less than 1 μg/ml of inorganic phosphate may be detected. This assay retains a unique principle of the former two, complexation (instead of reduction) of the phosphomolybdate heteropoly complex with an appropriate triphenylmethane dye (malachite green, methyl green). Use of detergents has been eliminated and some further properties of the dyes, the assay, and the latter's applicability to a coupled enzyme system for phosphomonoester and phosphodiester analysis are discussed. Consideration is also given to the associated phenomena of transphosphorylation. (Dayan, J., and Wilson, I. B. (1964) Biochim. Biophys. Acta81, 620–623).  相似文献   

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Six new polyketides aplojaveediins A–F (16) were isolated from the endophytic fungus Aplosporella javeedii associated with the host plant Orychophragmus violaceus (Brassicaceae). The structures of the new metabolites were elucidated by analysis of their NMR and MS data. Compound 1 exhibited antifungal activity against the hyphae form of Candida albicans strain ATCC 24433 in the agar plate diffusion assay and the microbroth dilution assay. The kinetic of killing of C. albicans cells for compound 1 was considerably faster than that of the positive control hygromycin B. Compounds 1 and 6 also exhibited moderate antibacterial activities against sensitive (ATCC 29213) and drug-resistant (ATCC 700699) strains of Staphylococcus aureus.  相似文献   

8.
Seed coat color inheritance in Brassica napus was studied in F1, F2, F3 and backcross progenies from crosses of five black seeded varieties/lines to three pure breeding yellow seeded lines. Maternal inheritance was observed for seed coat color in B. napus, but a pollen effect was also found when yellow seeded lines were used as the female parent. Seed coat color segregated from black to dark brown, light brown, dark yellow, light yellow, and yellow. Seed coat color was found to be controlled by three genes, the first two genes were responsible for black/brown seed coat color and the third gene was responsible for dark/light yellow seed coat color in B. napus. All three seed coat color alleles were dominant over yellow color alleles at all three loci. Sequence related amplified polymorphism (SRAP) was used for the development of molecular markers co-segregating with the seed coat color genes. A SRAP marker (SA12BG18388) tightly linked to one of the black/brown seed coat color genes was identified in the F2 and backcross populations. This marker was found to be anchored on linkage group A9/N9 of the A-genome of B. napus. This SRAP marker was converted into sequence-characterized amplification region (SCAR) markers using chromosome-walking technology. A second SRAP marker (SA7BG29245), very close to another black/brown seed coat color gene, was identified from a high density genetic map developed in our laboratory using primer walking from an anchoring marker. The marker was located on linkage group C3/N13 of the C-genome of B. napus. This marker also co-segregated with the black/brown seed coat color gene in B. rapa. Based on the sequence information of the flanking sequences, 24 single nucleotide polymorphisms (SNPs) were identified between the yellow seeded and black/brown seeded lines. SNP detection and genotyping clearly differentiated the black/brown seeded plants from dark/light/yellow-seeded plants and also differentiated between homozygous (Y2Y2) and heterozygous (Y2y2) black/brown seeded plants. A total of 768 SRAP primer pair combinations were screened in dark/light yellow seed coat color plants and a close marker (DC1GA27197) linked to the dark/light yellow seed coat color gene was developed. These three markers linked to the three different yellow seed coat color genes in B. napus can be used to screen for yellow seeded lines in canola/rapeseed breeding programs.  相似文献   

9.
The gonadogenesis was studied in adult and juvenile females of Japanese mitten crab Eriocheir japonicus (Crustacea: Decapoda, Grapsida) inhabiting the rivers of the Maritime Territory. The morphometric parameters of oocytes at different stages of maturity were determined using the methods of computer morphometry and color characteristics were evaluated using the Munsell Book of Color. As a result, a color table was compiled for the ovaries from the beginning of development to gonad maturity, which included light yellow (sandy), yellow, beige, light purple, light brown, dark purple, brown (chocolate), and dark brown (brown). The regular changes in the ovary color of E. japonicus proved to closely correlate with the gonadogenesis, namely, with the composition of cells at each stage of gonad maturity.  相似文献   

10.
Using light-emitting diode spotlights, we examined the responses of Cotesia vestalis, a parasitoid of diamondback moth (DBM), Plutella xylostella larvae, with different hunger level to different chromatic cues. Naïve satiated female wasps showed no significant preference for either green, yellow, orange, or red spotlighted areas over a control area with background fluorescent light. When starved for 2 h, female wasps preferred yellow and green light over the control area, but not orange or red light. We also tested the effects of DBM-larvae-induced cabbage-plant volatiles, which attract female wasps, on wasp responses to green versus yellow light. In control experiments with no plant volatiles, starved wasps showed no color preference. However, when synthetic volatiles were present, the wasps preferred green over yellow light. We concluded that both hunger level and herbivore-induced plant volatiles were important factors affecting the response of parasitic wasps to light of different color.  相似文献   

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Four novel Mo(II) and Rh(II) complexes with cis-1,2-dicyano-1,2-bis(2,4,5-trimethyl-3-thienyl)ethene (cis-dbe) or closed-dbe were synthesized and characterized. Employing [M(O2CCF3)4] (M = Mo, Rh) with cis-dbe or closed-dbe afforded complex [Mo2(O2CCF3)4(cis-dbe)](benzene) (1), [Rh2(O2CCF3)4(cis-dbe)](benzene) (2), [{Mo2(O2CCF3)4}2(closed-dbe)] (3), and [Rh2(O2CCF3)4(closed-dbe)](p-xylene) (4). The structures of four metal complexes were revealed by X-ray crystallographic analyses and the correlation between the crystal structures and the photochromic performance was discussed. In all complexes, two cyano groups of the ligand bridged two dimetal carboxylates to give a 1-D zigzag infinite chain structure. Upon irradiation with 405 nm light, complex 1 turned into reddish purple from yellow, and the color reverted to initial yellow on exposure to 563 nm light, indicating the reversible cyclization/ring-opening reaction in the crystalline phase. However, the Rh(II) complex 2 did not display similarities in reaction induced by light, which is attributable to the lower ratio of photoactive anti-parallel conformers compared with complex 1 and coordination effect of metal ions on photochromism of diarylethenes. The complexes of Rh(II) ions did not exhibit the expected reversible photoinduced behavior.  相似文献   

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14.
A new and convenient method for the determination of Pi was developed. Phosphomolybdate is measured colorimetrically, without reduction to molybdenum blue, by dissolving the whole assay mixture in acetone, where phosphomolybdate is bright yellow. The hydrolysis of acid-labile phosphates (e.g., creatine phosphate) causes no problems, because extra molybdate is complexed with citrate immediately after the color has been developed. Strong reductants and SH compounds which interfere, if present in high concentrations, are eliminated by adding H2O2. Detergents, organic bases, protein, and sucrose do not interfere. The assay is as sensitive as most modifications of the Fiske-SubbaRow method. In the routine procedure the useful range is 50–1500 nmol of Pi. The application of the method to the assay of inorganic pyrophosphatase in the cells of Escherichia coli is described.  相似文献   

15.
The assay for transaminase B (EC 2.6.1.6) activity, developed by D. E. Duggan and J. A. Wechsler (1973, Anal. Biochem.51, 67–79) has been modified to allow for the measurement of activity in Escherichia coli cells made permeable by cetyltrimethylammonium bromide (CETAB). A concentration of 10 mg% CETAB was found to be most effective in treating the cells without having a significant effect on transaminase B activity. Extraction of the dinitrophenylhydrazone of 2-oxoisovalerate by toluene was not affected by the CETAB treatment. We further report that the Na2CO3 extraction step is not required to measure color formed by the dinitrophenylhydrazone of 2-oxoisovalerate. This CETAB-treated cell assay is accurate to study transaminase B activity through most of the logarithmic phase of growth of Escherichia coli.  相似文献   

16.
As a continuation of previous research on a new series of potent and efficacious P-gp-dependent multidrug resistant (MDR) reversers with a N,N-bis(cyclohexanol)amine scaffold, we have designed and synthesized several analogs by modulation of the two aromatic moieties linked through ester functions to the N,N-bis(cyclohexanol)amine, aiming to optimize activity and to extend structure–activity relationships (SAR) within the series. This scaffold, when esterified with two different aromatic carboxylic acids, gives origin to four geometric isomers (cis/trans, trans/trans, cis/cis and trans/cis).The new compounds were tested on doxorubicin-resistant erythroleukemia K562 cells (K562/DOX) in the pirarubicin uptake assay. Most of them resulted in being potent modulators of the extrusion pump P-gp, showing potency values ([I]0.5) in the submicromolar and nanomolar range. Of these, compounds 2b, 2c, 3d, 5ad and 6d, showed excellent efficacy with a αmax close to 1. Selected compounds (2d, 3a, 3b, 5ad) were further studied to evaluate their doxorubicin cytotoxicity potentiation (RF) on doxorubicin-resistant erythroleukemia K562 cells and were found able to enhance significantly doxorubicin cytotoxicity on K562/DOX cells.The results of both pirarubicin uptake and the cytotoxicity assay, indicate that the new compounds of the series are potent P-gp-mediated MDR reversers. They present a structure with a mix of flexible and rigid moieties, a property that seems critical to allow the molecules to choose the most productive of the several binding modes possible in the transporter recognition site.In particular, compounds 5c and 5d, similar to the already reported analogous isomers 1c and 1d,29 are potent and efficacious modulators of P-gp-dependent MDR and may be promising leads for the development of MDR-reversal drugs.  相似文献   

17.
A sensitive and selective assay for the determination of N-{1(R)-[(1,2-dihydro-1-methylsulfonylspiro[3H-indole-3,4′-piperidin]-1′-yl)carbonyl]-2-(phenylmethoxy)-ethyl}-2-hydroxyamino-2-methylpropanamide (I), a hydroxyl amine metabolite of a novel growth hormone secretagouge (II) has been developed utilizing high-performance liquid chromatography with ion spray tandem mass spectrometric detection (HPLC–MS–MS). The analyte and an internal standard (III) were isolated from the basified biological matrix using a liquid–liquid extraction with methyl tert.-butyl ether (MTBE). The organic extract was evaporated to dryness at room temperature. The residue was reconstituted in the mobile phase and injected into the HPLC–MS–MS system. Multiple reaction monitoring using the precursor→product ion combinations of m/z 545→267 and 543 →267 was used to quantify I and III, respectively, after chromatographic separation under isocratic conditions. The assay was validated in the concentration range of 0.5 to 500 ng/0.1 ml in both human and dog plasma. The precision of the assay, expressed as relative standard deviation, was less than 10% over the entire concentration range with the exception of the low concentration of 0.5 ng/0.1 ml which was 14.0% for human plasma. The HPLC–MS–MS method provided sufficient sensitivity to completely map the pharmacokinetic time course of I following a single 5 mg dose of II to human subjects and a 0.5 mg/kg dose to beagle dogs.  相似文献   

18.
The Lowry method (G. H. Lowry, N. J. Rosebrough, A. L. Farr, and R. J. Randall, 1951, J. Biol. Chem.193, 265–275) for protein concentration measurement has been automated to permit assay of samples with concentrations from 1 to 400 μg/ml. Calibration with solutions of bovine serum albumin resulted in a nonlinear (quadratic) curve. The quantity of color developed in the assay was found to be strongly dependent on the concentration of the Folin-Ciocalteu phenol reagent. Color yield peaked sharply at a reagent concentration 40% lower than that used in the Lowry procedure. Optimization of the reagent concentration is necessary to obtain maximum sensitivity from the Lowry assay.  相似文献   

19.
As a part of our continuing program on the synthesis of steroidal heterocycles, it has been prepared a series of novel steroidal pyrimidine derivatives 46 via TMSCl, steroidal ketones (1c3c), urea and benzaldehyde. The systems presented here, are novel scaffolds and have not been described before at 6th position of steroidal-6-one (1c–3c). Structural assignment of newly synthesized compounds was performed by DFT/B3LYP calculations as well as spectral and analytical data. The interactions of compounds (46) with HSA were studied by fluorescence spectroscopy, DLS, CD and molecular docking, under imitated physiological conditions. The antitumor activity has been tested in vitro against three cancer cell lines MDA-MB231 (breast carcinoma), HeLa (human cervical carcinoma), HepG2 (hepatic carcinoma) and one non-cancer normal cell lines, PBMCs (peripheral blood mononuclear cell) by MTT assay. In addition, in vitro antioxidant activity and apoptosis assay of the synthesized compounds (46) have also been investigated.  相似文献   

20.
Two novel flavonoids, named meliflavones A (1) and B (2), were isolated from the leaves of Melicope triphylla (Lam.) Merr., along with thirteen known compounds (315). Four of the polymethoxyflavonoids bearing a prenyloxy (3-methylbut-2-enyloxy) function (1, 35) induced the expression of extracellular-superoxide dismutase (EC-SOD) in a human leukemic U937 cell-based assay.  相似文献   

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