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1.
Using agroinfection with a T-DNA vector carrying a hygromycin resistance marker, the recombinants were generated for the first time from the ectomycorrhizal basidiomycete Tricholoma matsutake, which produces commercially valuable fruit bodies, matsutake, during association with Pinus sp. plants. The transformation system may be useful in the genetic analysis of T. matsutake.  相似文献   

2.
A new H(2)O(2)-generating pyranose oxidase was purified as a strong antifungal protein from an arbuscular mycorrhizal fungus, Tricholoma matsutake. The protein showed a molecular mass of 250 kDa in gel filtration, and probably consisted of four identical 62 kDa subunits. The protein contained flavin moiety and it oxidized D-glucose at position C-2. H(2)O(2) and D-glucosone produced by the pyranose oxidase reaction showed antifungal activity, suggesting these compounds were the molecular basis of the antifungal property. The V(max), K(m), and k(cat) for D-glucose were calculated to be 26.6 U/mg protein, 1.28 mM, and 111/s, respectively. The enzyme was optimally active at pH 7.5 to 8.0 and at 50 degrees C. The preferred substrate was D-glucose, but 1,5-anhydro-D-glucitol, L-sorbose, and D-xylose were also oxidized at a moderate level. The cDNA encodes a protein consisting of 564 amino acids, showing 35.1% identity to Coriolus versicolor pyranose oxidase. The recombinant protein was used for raising the antibody.  相似文献   

3.
松茸组织分离物的rDNA-ITS序列鉴定   总被引:1,自引:0,他引:1  
以采自云南丽江的松茸子实体为材料,进行组织分离后,利用一对ITS引物(ITS1-ITS4)对子实体(SR176B,SR172B)和分离物(SR176H,SR172H)进行了PCR扩增、琼脂糖凝胶电泳分析,得到了700bp左右的扩增条带,进一步对ITS序列进行同源性检索比对,结果表明SR176H与SR176B,SR172H与SR172B序列同源性均为100%,鉴定出该分离物就是松茸的纯培养物。  相似文献   

4.
对斜链拟青霉胞外多糖进行体外清除自由基活性研究。利用醇沉法从斜链拟青霉发酵液中醇沉获得斜链拟青霉胞外多糖,经DEAE-纤维素-52柱层析后得到1个主峰P3和2个小峰P1与P2,对主峰P3进行Sephadex G-100柱层析,表明P3为纯化物; 应用DPPH-酶标法和化学发光法分别对P3进行清除DPPH·、·OH和O-2·能力测试。结果表明:P3对DPPH·、·OH和O-2·均具有明显的清除能力,且与浓度呈量效关系,IC50分别为0.083、0.121和0.214 mg/mL。  相似文献   

5.
《菌物学报》2017,(9):1271-1277
利用水提醇沉法对桦褶孔菌Lenzites betulina粗多糖HZKJc进行提取,随后经Sevage法和酶法联合脱蛋白,再经DEAE‐Sephadex A‐25,G‐100柱层析纯化后得到多糖纯品HZKJv。通过高效液相色谱(HPLC)测定上述纯化多糖的纯度和相对分子量分布;经纸层析(PC)、气相色谱(GC)、红外光谱(IR)进行单糖组成分析;并研究其清除自由基活性。分离纯化后得到的HZKJv为纯多糖,相对分子质量约为11 687。当HZKJv溶液浓度为3.0mg/m L时,其DPPH自由基清除率可达82%;浓度为2.0mg/m L时,对?OH自由基的清除率可达85%。表明HZKJv对?OH与DPPH自由基存在很好的清除作用。  相似文献   

6.
Mushrooms are regarded as one of the well-known foods and biopharmaceutical materials with a great deal of interest. Polysaccharide beta-glucan is the major component of mushrooms that displays various biological activities such as antidiabetic, anticancer, and antihyperlipidemic effects. In this study, we compared the immunostimulatory potency of polysaccharide fractions, prepared from liquid culture of pinemushroom Tricholoma matsutake, with a potent immunogen lipopolysaccharide (LPS), and their molecular mechanisms on the functional activation of macrophages. We found that fraction II (TMF-II) was able to comparably upregulate or highly enhance the phenotypic functions of macrophages such NO production and cytokine (IL-1beta, IL-6, IL-12, and TNF-alpha) expression, to LPS. TMF-II triggered the phosphorylation of IkappaBalpha, a critical step for NF-kappaB activation and translocation. Of the upstream signaling enzymes tested, Src and Akt were thought to be the responsible upstream signaling components in induction of NO production, although TMF-II strongly upregulated the phosphorylation of all MAPK pathways. Therefore, our data suggest that T. matsutake-derived beta-glucan may exert its immunostimulating activities with similar potency to LPS via activation of multiple signaling pathways linked to NF-kappaB activation.  相似文献   

7.
A peptide having the strong free radical scavenging activities was separated from casein protein hydrolysate by chromatographic analyses such as ion-exchange and gel filtration. SP-II fraction obtained by SP-Sephadex C-25 chromatography showed the most potent superoxide anion scavenging activity (SOSA), and it was further separated into a peptide using an octadecylsilano-high performance liquid chromatography. The amino acid sequence of the peptide was Tyr-Phe-Tyr-Pro-Glu-Leu (YFYPEL). The concentration of the test compound required to reduce the produced superoxide anion to one-half (IC(50)) value for SOSA was 79.2 microM using tetrazolium salt 3'-{1-[(phenylamino)-carbonyl]-3,4-tetrazolium}-bis(4-methoxy-6-nitro)benzenesulfonic acid hydrate method. The IC50 value for the 1,1-diphenyl-2-picrylhydrazyl radical and hydroxyl radical scavenging activities were 98 and 251 microM, respectively, based on the electron spin resonance method. We characterized SOSA of the C-terminal sequence using EL, PEL, YPEL, and FYPEL. The activities preferred sequences were EL>YFYPEL>FYPEL>YPEL>PEL, suggesting that the Glu-Leu sequence is important for the activity.  相似文献   

8.
Sixty preparations of basidiomycetes (Ganoderma, Lentinus, Pleurotus, Laetiporus, Polyporus, Inonotus, Flammulina, Grifola, Trametes) were investigated with respect to their toxicity for Vero cells and antiviral activity. The antiviral activity was estimated with the use of the West Nile virus and type 2 Herpes simplex. It was shown that 11 preparations of Ganoderma, Lentinus and Pleurotus completely inhibited the infective activity in doses not lower than 1000 TCD50 (the West Nile virus) and 100 PPU (type 2 Herpes simplex). The antiviral activity of the preparations was likely due to the content of polysaccharides or their derivatives in the composition. It increased with increasing of the quantity of the total polysaccharide fraction or its concentration.  相似文献   

9.
The present investigation deals with the isolation of a polysaccharide fraction from Pomegranate (PFP), which was found to inhibit 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-Azinobis[3-ethylbenzothiazoline-6-sulfonate] ABTS(+) radical activities by 69% and 88%, respectively with 4 microg/ml concentration. The activity of PFP for free radical scavenging was also evaluated by electron spin resonance (ESR) Spectrophotometer and DPPH dot blot test. Anti-glycation ability of PFP was tested using BSA, which inhibited the formation of advanced glycation end-products (AGEs) by 28% and also inhibited the formation of fructosamine in the BSA/Glucose system. The inhibition of mushroom tyrosinase by 43% at 10 microg/ml concentration of PFP strongly suggested its efficacy as a possible skin whitener.  相似文献   

10.
家蝇幼虫活性蛋白组分的提取及清除羟基自由基活性研究   总被引:3,自引:0,他引:3  
以家蝇MuscadomesticaL.幼虫(蝇咀)为材料,根据溶解度的不同,从脱脂蝇蛆粉中分离出清蛋白、小分子肽、球蛋白、醇溶蛋白、碱溶蛋白等5类蛋白,并测定了它们的含量。结果表明:清蛋白、球蛋白和小分子肽是组成脱脂蝇蛆粉蛋白的主要成分。体外的抗氧化活性实验结果表明:清蛋白和球蛋白都有很好的清除羟基自由基的作用。  相似文献   

11.
A new H2O2-generating pyranose oxidase was purified as a strong antifungal protein from an arbuscular mycorrhizal fungus, Tricholoma matsutake. The protein showed a molecular mass of 250 kDa in gel filtration, and probably consisted of four identical 62 kDa subunits. The protein contained flavin moiety and it oxidized D-glucose at position C-2. H2O2 and D-glucosone produced by the pyranose oxidase reaction showed antifungal activity, suggesting these compounds were the molecular basis of the antifungal property. The V max, K m, and k cat for D-glucose were calculated to be 26.6 U/mg protein, 1.28 mM, and 111/s, respectively. The enzyme was optimally active at pH 7.5 to 8.0 and at 50°C. The preferred substrate was D-glucose, but 1,5-anhydro-D-glucitol, L-sorbose, and D-xylose were also oxidized at a moderate level. The cDNA encodes a protein consisting of 564 amino acids, showing 35.1% identity to Coriolus versicolor pyranose oxidase. The recombinant protein was used for raising the antibody.  相似文献   

12.
Selectin-mediated leukocyte initial attachment and rolling over vessel endothelial surface are crucial steps for inflammatory responses. As P-selectin is a promising target for anti-inflammation therapeutic strategy, recent works have focused on searching for more potent and non-toxic P-selectin antagonists among various natural carbohydrate products. Here, we isolated three water-soluble polysaccharide fractions (PPS-1, PPS-2 and PPS-3) from the roots of Physalis alkekengi by DEAE-cellulose and Sephacryl S-200 chromatography. Their physicochemical and structural characterizations were determined by chemical methods, GC (gas chromatography), HPLC (high performance liquid chromatography), FT-IR (Fourier transform infrared spectrometry), partial acid hydrolysis, methylation and GC-MS (gas chromatography-mass spectrometry) analyses. The inhibitory capacity of the polysaccharide fractions in P-selectin-mediated leukocyte adhesion was evaluated by flow cytometric, static adhesion and laminar flow assays. Results showed that different polysaccharide fractions possess distinct physicochemical and structural properties, including carbohydrate, protein and uronic acid contents, molecular weight, monosaccharide composition and glycosidic linkage type. Among the polysaccharide fractions, PPS-2 could effectively block the interaction between P-selectin and its native ligand.  相似文献   

13.
Purification and chemical characterization of an immunosuppressive exopolysaccharide from Capnocytophaga ochracea strain 25 are described. This polysaccharide was extracted from spent culture medium by cold ethanol precipitation. Purification was accomplished by trichloroacetic acid and pronase treatments in combination with diethylaminoethyl-Sepharose and concanavalin A-Sepharose chromatography. Purity of the exopolysaccharide was ascertained by polyacrylamide gel electrophoresis using periodic acid--Schiff staining. The exopolysaccharide was free of protein, nucleic acid, and lipopolysaccharide, but contained large amounts of mannose with lesser quantities of glucose, galactose, glucuronic acid, and glucosamine.  相似文献   

14.
Zhang  Zuo  Shi  Menghua  Zheng  Hanyu  Ren  Ruifang  Zhang  Shaopeng  Ma  Xiaolong 《Glycoconjugate journal》2022,39(3):369-380
Glycoconjugate Journal - Morchella is the famous medicinal fungi in the ascomycetes. In this study, a new water-soluble polysaccharide (MSP-3-1) with an average molecular weight of 2.35 × 107...  相似文献   

15.
Type 1 pili were purified from a Klebsiella pneumoniae strain isolated from a human urinary tract infection. The pili were removed from the bacteria by mechanical shearing, precipitated out of solution by ammonium sulfate, solubilized in a deoxycholate-containing buffer, and finally purified by gel filtration. Chemical characterization of the isolated pili revealed a single protein subunit (pilin) which had a Mr = 21,500. Amino acid compositional analysis revealed a high content of residues that contribute significantly to secondary structure. Automated sequence analysis of the NH2-terminal region revealed a striking homology (79% identity) with type 1 pili of Escherichia coli. In contrast, NH2-terminal sequence comparison of K. pneumoniae pilin with other previously reported bacterial pilins showed no significant homology. No immunological cross-reactivity was detectable between E. coli and K. pneumoniae pili when tested by Ouchterlony double immunodiffusion or by rocket immunoelectrophoresis. The results of this study, when compared to other studies of bacterial pili, indicate that type 1 pili from members of the Enterobacteriaceae share morphological similarities and that their monomeric subunits are chemically similar. In addition, these results give strong evidence that the type 1 pilins of the enteric bacteria represent a separate class of homologous pilins.  相似文献   

16.
To obtain a natural antioxidant from a marine biomass, this study investigated the antioxidative activity of methanolic extracts from the marine brown alga, Ishige okamurae collected off Jeju Island. A potent free radical scavenging activity was detected in the ethyl acetate fraction containing polyphenolic compounds, and the potent antioxidant elucidated as a kind of phlorotannin, diphlorethohydroxycarmalol, by NMR and mass spectroscopic data. The free radical scavenging activities of the diphlorethohydroxycarmalol were investigated in relation to 1,1-diphenyl-2-picrylhydrazyl (DPPH), alkyl, and hydroxyl radicals using an electron spin resonance (ESR) system. The diphlorethohydroxycarmalol was found to scavenge DPPH (IC50=3.41 microM) and alkyl (IC50=4.92 microM) radicals more effectively than the commercial antioxidant, ascorbic acid. Therefore, these results present diphlorethohydroxycarmalol as a new phlorotannin with a potent antioxidative activity that could be useful in cosmetics, foods, and pharmaceuticals.  相似文献   

17.
Three sulfated polysaccharide fractions (F1, F2, and F3) were isolated from Porphyra haitanesis, an important economic alga in China, through anion-exchange column chromatography and their in vitro antioxidant activities were investigated in this study. Galactose was the main sugar unit of the three fractions. The analytical results indicated that polysaccharide fractions from P. haitanesis had similar chemical components to porphyran from other species, but differed in their high sulfate content. The sulfate content of F1, F2 and F3 was 17.4%, 20.5% and 33.5% respectively. All three polysaccharide fractions showed antioxidant activities. They had strong scavenging effect on superoxide radical, and much weaker effect on hydroxyl free radical. Lipid peroxide in rat liver microsome was significantly inhibited, and H2O2 induced hemolysis of rat erythrocyte was partly inhibited by F1, F2 and F3. Among them, F3 showed strongest scavenging effect on superoxide radical; F2 had strongest effect on hydroxyl radical and lipid peroxide.  相似文献   

18.
In the course of screening for immunomodulators, we found a significant blastogenic activity specific for splenic B cells in the extracts of safflower (Carthamus tinctorius L.). Active fractions termed SF1 and SF2 were purified from dried petals of safflower by boiling water extraction, ethanol precipitation and Sepharose CL-2B column chromatography. The elution profiles of the gel filtration indicated that the molecular weight of SF1 and SF2 was estimated to be more than 100 kD. Major components of SF1 and SF2 seem to be polysaccharides, and structural analysis of alditol acetate derivatives by GC-MS revealed some differences between SF1 and SF2 in the sugar component. Biological activities of SF1 and SF2 on B cells and macrophages were examined in comparison with lipopolysaccharides (LPS). SF1 and SF2 induced both the proliferation and the IgM production of B cells to the equivalent level as those induced by LPS. In macrophages, SF1 and SF2 effectively stimulated the production of NO. However, SF1 stimulated the production of IL-1, IL-6, and TNF as much as LPS, while SF2 induced them only weakly or not at all. Thus, these results suggest that SF1 and SF2 activate B cells and macrophages in different mechanisms. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

19.
20.
The synthesis and antioxidant evaluation of some novel benzimidazole derivatives (1024) are described. Antioxidant properties of the compounds were investigated employing various in vitro systems viz., microsomal NADPH-dependent inhibition of lipid peroxidation (LP), interaction of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and scavenging of superoxide anion radical. Compounds 12 and 13 showed very good antioxidant capacity and were 17–18 -fold more potent than BHT (IC50 2.3 × 10? 4M) with 1.3 × 10? 5M and 1.2 × 10? 5M IC50 values, respectively, by interaction of the stable DPPH free radical.  相似文献   

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