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1.
Antrodia camphorata is a unique medicinal mushroom found only in Taiwan. It has been used as a remedy for various diseases in folk medicine. Antrodia camphorata has been shown to exhibit antioxidative effects. Peroxiredoxins play important roles in antioxidation and cell signaling. A gene encoding an antioxidant enzyme, 1-cysteine peroxiredoxin (1-Cys Prx), was identified in an expressed sequence tag database of the A. camphorata and cloned by polymerase chain reaction. The 1-Cys Prx cDNA (837 bp, accession no. AY870325) contains an open reading frame encoding a protein of 223 amino acid residues with calculated molecular mass of 25,081 Da. The deduced protein shared 44–58% identity with 1-Cys Prx from Homo sapiens, Bos taurus, and Saccharomyces cerevisia. The sequence surrounding the conserved cysteine DFTPVCTTE is conserved. The coding sequence was subcloned into a vector, pET-20b (+), and transformed into Escherichia coli. The recombinant 1-Cys Prx was purified by Ni2+-nitrilotriacetic acid (Sepharose). The purified enzyme was characterized under various conditions. The enzyme is thermostable because its half-life of inactivation was 15.5 min at 60°C. It was stable under alkaline pH range from 7.8 to 10.2. The enzyme showed decreased activity with increasing concentration of imidazole. The enzyme is sensitive to trypsin and chymotrypsin treatment. Lisa Wen, Hui-Ming Huang, and Rong-Huay Juang contributed equally to this paper.  相似文献   

2.
The species of Antrodia are one of the difficult-to-classify and obscure groups of poroid Aphyllophorales based on morphological appearance. However, it is becoming increasingly important to reliably identify the entire suite of Antrodia camphorata strains and Antrodia species due to the potential pharmaceutical value of their biologically active ingredients. In this study, the internal transcribed spacer (ITS) region of the ribosomal RNA gene (rDNA) was sequenced and phylogenetically analyzed in a number of Antrodia fungal species and strains. ITS amplicons from the Antrodia species tested ranged in size from 543 to 610 bp; the size of the ITS of A. camphorata strains ranged from 592 to 596 bp. The overall sizes of ITS2 and 5.8S ribosomal RNA gene of all A. camphorata strains tested in this study were shown to be 217 and 158 bp, respectively. A phylogenetic analysis of ITS data generated, which included sequences of 11 A. camphorata strains and nine other Antrodia species, showed three clearly distinct groups. Group 1 includes A. camphorata, Antrodia salmonea, and Antrodia carbinca strains. Within Group 2, Antrodia sinuosa and Antrodia xantha were clustered together. Group 3 contained Antrodia albida, A. heteromorpha, A. serialis, and A. malicola. The observed sequence diversity among ITS alleles provided an effective tool for differentiating strains of A. camphorata, A. salmonea, A. xantha, A. sinuosa, or A. serialis. Polymorphisms arising within the ITS1-5.8S-ITS2 region can provide practical markers for establishing a foundation for the further expansion of an ITS sequence database of medically important fungi.  相似文献   

3.
Peroxiredoxins (Prxs) play important roles in antioxidation and cell signaling. A gene encoding a novel 2-Cys Prx was identified based on sequence homology in an expressed sequence tag database of the Antrodia camphorata, a medicinal mushroom found only in Taiwan. The 2-Cys Prx cDNA (940 bp) encodes a protein of 188 amino acid residues with calculated molecular mass of 20,965 Da and a pI of 5.89. The coding region was subcloned into pAVD10, transformed into Escherichia coli, and expressed as a His-tagged fusion protein. The purified enzyme was characterized under various conditions. The Prx retained 68% activity after being heated at 60°C for 2 min. It was stable under a broad pH range from 5 to 11. The enzyme activity was slightly decreased in the presence of 1% sodium dodecyl sulfate. The enzyme was somewhat susceptible to chymotrypsin treatment but resistant to digestion by trypsin. Jenq-Kuen Huang, Chuian-Fu Ken, and Hui-Ming Huang contributed equally to this paper.  相似文献   

4.
A comprehensive inventory of the organic components and aroma-active compounds produced by Antrodia camphorata during growth in submerged culture has been established by extracting culture fluids using three different organic solvent systems and subjecting the extracts to gas chromatography-mass spectrometry (GC–MS) and gas chromatography–olfactometry (GC-O). Forty-two organic components, of which esters, alcohols, acids and ketones were the most prevalent, were identified in pentane/ether (1/1, v/v) extracts. The most representative of A. camphorata aroma-active compounds were detected in pentane/ether and ether extracts (eleven and nine aroma-active compounds, respectively) by GC-O. Of these, ethyl acetate, γ-undecalactone, linaloöl and 3-hydroxy-2-butanone were assessed to be present at the highest intensity.  相似文献   

5.
Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes.  相似文献   

6.
The effects of cultivation medium compositions including soybean meal, peptone, soybean oil and cornstarch for actinomycin X2 production by Streptomyces spp JAU4234 were accessed by using response surface methodology. The 2(4) full factorial designs and the paths of steepest ascent were effective in searching for the major factors of actinomycin X2 production. In this study, cornstarch and soybean oil showed negative effect on actinomycin X2 production based on the first-order regression coefficients derived from MINITAB software. Subsequently, a central composite design for optimization was further investigated. Preliminary studies showed that soybean meal and peptone were believed to be the major factors for actinomycin X2 production. Estimated optimum compositions for the production of actionmycin X2 were as follows (g/l): soybean meal 21.65 and peptone 9.41, and result in a maximum actionmycin X2 production of 617.4 mg/l. This value was closed to the 612 mg/l actionmycin X2 production from actual experimental observations. The yield of actionmycin X2 was increased by 36.9% by culturing the strain Streptomyces spp JAU4234 in the nutritionally optimized fermentation medium.  相似文献   

7.
A revision of Penstemon sect. Saccanthera subsect. Serrulati includes a new species (P. salmonensis), a new variety (P. triphyllus var. infernalis), and the elevation of a subspecies to species (P. curtiflorus), bringing the total number of species to eight, which are keyed and described, complete with nomenclature and type citations.  相似文献   

8.
A genetic transformation system has been developed for callus cells of Crataegus aronia using Agrobacterium tumefaciens. Callus culture was established from internodal stem segments incubated on Murashige and Skoog (MS) medium supplemented with 5 mg l−1 Indole-3-butyric acid (IBA) and 0.5 mg l−1 6-benzyladenine (BA). In order to optimize the callus culture system with respect to callus growth and coloration, different types and concentrations of plant growth regulators were tested. Results indicated that the best average fresh weight of red colored callus was obtained on MS medium supplemented with 2 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.5 mg l−1 kinetin (Kin) (callus maintenance medium). Callus cells were co-cultivated with Agrobacterium harboring the binary plasmid pCAMBIA1302 carrying the mgfp5 and hygromycin phosphotransferase (hptII) genes conferring green fluorescent protein (GFP) activity and hygromycin resistance, respectively. Putative transgenic calli were obtained 4 weeks after incubation of the co-cultivated explants onto maintenance medium supplemented with 50 mg l−1 hygromycin. Molecular analysis confirmed the integration of the transgenes in transformed callus. To our knowledge, this is the first time to report an Agrobacterium-mediated transformation system in Crataegus aronia.  相似文献   

9.
Studying Pneumocystis has proven to be a challenge from the perspective of propagating a significant amount of the pathogen in a facile manner. The study of several fungal pathogens has been aided by the use of invertebrate model hosts. Our efforts to infect the invertebrate larvae Galleria mellonella with Pneumocystis proved futile since P. murina neither caused disease nor was able to proliferate within G. mellonella. It did, however, show that the pathogen could be rapidly cleared from the host.  相似文献   

10.
Bacteria of the Bacillus species have been reported as an important microorganism in fermented soybean products. In the present study, thirty Bacillus isolates were screened from Meju, a Korean soybean fermentation starter. The comparative analysis of 16S rDNA sequences, 16S-23S internal transcribed spacer sequences, phenotypic, and biochemical characterizations revealed three phylogenetically distinct groups namely Bacillus atrophaeus, Bacillus polyfermenticus and Bacillus subtilis. The isolates were assayed for poly-γ-glutamate production and fibrinolytic activity. Among the isolates, B. polyfermenticus exhibited maximum poly-γ-glutamate production and fibrinolytic activity. Moreover, the soybean products fermented by B. polyfermenticus have increased the time taken for coagulation and hemorrhage in mice. The results of the present study clearly indicate the functional role of B. polyfermenticus in fermented soybean products.  相似文献   

11.
A mixed trophic state production process for algal lipids for use as feedstock for renewable biofuel production was developed and deployed at subpilot scale using a green microalga, Auxenochlorella (Chlorella) protothecoides. The process is composed of two separate stages: (1) the photoautotrophic stage, focused on biomass production in open ponds, and (2) the heterotrophic stage focused on lipid production and accumulation in aerobic bioreactors using fixed carbon substrates (e.g., sugar). The process achieved biomass and lipid productivities of 0.5 and 0.27 g/L/h that were, respectively, over 250 and 670 times higher than those obtained from the photoautotrophic cultivation stage. The biomass oil content (over 60 % w/DCW) following the two-stage process was predominantly monounsaturated fatty acids (~82 %) and largely free of contaminating pigments that is more suitable for biodiesel production than photosynthetically generated lipid. Similar process performances were obtained using cassava hydrolysate as an alternative feedstock to glucose.  相似文献   

12.
Butyric acid fermentation by Clostridium tyrobutyricum ATCC 25755 using glucose or brown algae as a carbon source was carried out. Initially, different fermentation modes (batch, fed-batch, and semi-continuous) at pH 6 and 37°C were compared using a model medium containing glucose as a carbon source. By feeding the whole medium containing 40 ∼ 50 and 30 g/L of glucose into the fed-batch and semi-continuous fermentations, very similar butyrate yields (0.274 and 0.252 g butyrate/g glucose, respectively) and productivities (0.362 and 0.355 g/L/h, respectively) were achieved. The highest butyrate concentration was about 50 g/L, which was observed in the fed-batch fermentation with whole medium feeding. However, semi-continuous fermentation sustained a longer fermentation cycle than the fed-batch fermentation due to end-product and metabolic waste inhibition. The established conditions were then applied to the fermentation using brown algae, Laminaria japonica and Undaria pinnatifida, as substrates for butyric acid fermentation. To hydrolyze brown algae, 7.5 ∼ 10% (w/v) dried brown algae powder was suspended in 1% (w/v) NaOH or 0.5 ∼ 2.5% (w/v) H2SO4 and then autoclaved at 121°C for 30 ∼ 90 min. The resulting butyrate concentration was about 11 g/L, which was produced from 100 g/L of L. japonica autoclaved for 60 min in 1.5% H2SO4 acid solution.  相似文献   

13.
The structural gene for sphingomyelinase (SMase) from Streptomyces griseocarneus, was introduced into Streptomyces lividans using a shuttle vector, pUC702, for Escherichia coli/S. lividans. High-level secretory production of SMase was achieved using the promoter, signal sequence and terminator regions of phospholipase D from Streptoverticillium cinnamoneum. The transformant constitutively expressed a high specific activity of SMase extracellularly during batch culture. Maximum SMase activity (555 ± 114 U/mg protein) was with 1.75 M MgCl2 which was about 50-fold more than that with 10 mM MgCl2.  相似文献   

14.
15.
The maT clade of transposons is a group of transposable elements intermediate in sequence and predicted protein structure to mariner and Tc transposons, with a distribution thus far limited to a few invertebrate species. We present evidence, based on searches of publicly available databases, that the nematode Caenorhabditis briggsae has several maT-like transposons, which we have designated as CbmaT elements, dispersed throughout its genome. We also describe two additional transposon sequences that probably share their evolutionary history with the CbmaT transposons. One resembles a fold back variant of a CbmaT element, with long (380-bp) inverted terminal repeats (ITRs) that show a high degree (71%) of identity to CbmaT1. The other, which shares only the 26-bp ITR sequences with one of the CbmaT variants, is present in eight nearly identical copies, but does not have a transposase gene and may therefore be cross mobilised by a CbmaT transposase. Using PCR-based mobility assays, we show that CbmaT1 transposons are capable of excising from the C. briggsae genome. CbmaT1 excised approximately 500 times less frequently than Tcb1 in the reference strain AF16, but both CbmaT1 and Tcb1 excised at extremely high frequencies in the HK105 strain. The HK105 strain also exhibited a high frequency of spontaneous induction of unc-22 mutants, suggesting that it may be a mutator strain of C. briggsae.  相似文献   

16.
Growth of Streptococcus zooepidemicus in a 10 l bioreactor with 50 g sucrose/l and 10 g casein hydrolysate/l gave 5–6 g hyaluronic acid/l after 24–28 h. Purification of hyaluronic acid gave a recovery of 65% with the final material having an Mr of ∼4 × 106 Da with less than 0.1% protein.  相似文献   

17.
Here we evaluate the origins and relationships of Mexican and Central American Diplazium hybrids derived from crosses involving either D. plantaginifolium or D. ternatum. Based on study of live plants and herbarium specimens, we distinguish D. ×verapax from the similar D. riedelianum and present evidence that the former is a sterile hybrid derived from a cross between D. plantaginifolium and D. werckleanum. We also describe new hybrids, D. ×torresianum and D. ×subternatum from Mexico and northern Central America. Both involve D. ternatum as one parent. Diplazium. cristatum is the other putative parent of D. ×torresianum, and D. plantaginifolium is the second parent of D. ×subternatum. We also designate lectotypes for D. cordovense and D. dissimile.  相似文献   

18.
Biosynthesis of polyketide compounds depends upon the starter and extender units of coenzyme A derivatives of carboxylic acids present in the host organism. To increase the coenzyme A (CoA) pool, pantothenate kinase (panK) gene from Escherichia coli was integrated into S. peucetius ATCC 27952 (panK-integrated strain, BG200), which resulted in increase in aglycone polyketide ε-rhodomycinone (RHO), but decrease in the desired product, i.e., doxorubicin (DXR). To reduce RHO accumulation by synthesizing daunorubicin (DNR) from RHO more efficiently, glycosyltransferase (dnrQS) was overexpressed (pIBR25::dnrQS in panK-integrated strain, BG201). However, DnrQS overexpression still resulted in less production of DXR compared with the parental strain. To understand the results in detail by investigating the proteome changes in the panK-integrated strain, two-dimensional (2D) gel electrophoresis was performed. Among the several proteins that are up- or downregulated in BG200, efflux protein DrrA was our main target of interest, because it is directly related to DXR/DNR production in S. peucetius. DXR transporter DrrAB was additionally introduced in BG200 to enhance secretion of toxic DXR. Compared with S. peucetius ATCC 27952, BG204 (pIBR25::drrAB in panK-integrated strain), produced two times higher amount of DXR, which is 9.4-fold higher than that of panK-integrated strain BG200. The results show that the proteomic approach is quite useful in host development of Streptomyces and understanding cell physiology for antibiotic production.  相似文献   

19.
Seol E  Jung Y  Lee J  Cho C  Kim T  Rhee Y  Lee S 《Plant cell reports》2008,27(7):1197-1206
Notocactus scopa cv. Soonjung was subjected to in planta Agrobacterium tumefaciens-mediated transformation with vacuum infiltration, pin-pricking, and a combination of the two methods. The pin-pricking combined with vacuum infiltration (20-30 cmHg for 15 min) resulted in a transformation efficiency of 67-100%, and the expression of the uidA and nptII genes was detected in transformed cactus. The established in planta transformation technique generated a transgenic cactus with higher transformation efficiency, shortened selection process, and stable gene expression via asexual reproduction. All of the results showed that the in planta transformation method utilized in the current study provided an efficient and time-saving procedure for the delivery of genes into the cactus genome, and that this technique can be applied to other asexually reproducing succulent plant species.  相似文献   

20.
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