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1.
酵母甘露聚糖(Mannan,简称Man)是能参与生物信息流影响生物体、特别是在糖基化方面起着重要调控作用的生物信息大分子.它是否能在抑制生物机体中肿瘤生长方面具有重要作用?研究结果表明:酵母甘露聚糖既能使患S-180瘤鼠的体质增强的同时又有抑制其体内所患S-180瘤生长的功效.Man抑制患鼠机体内的S-180瘤生长的功效(抑瘤率)随用量的增加而提高,当Man用量达360 mg(40 mg/Kg/d·9d)时,其抑瘤率达98.4%的最高水平,此时鼠体重增加1.66倍.Man的抑瘤功效有最佳适用量并存在性别敏感性,通常是雄性鼠的抑瘤率高于雌性鼠.Man抑制鼠S-180肿瘤生长的作用优于市售5-氟尿嘧啶的作用.  相似文献   

2.
为了进一步了解酵母甘露聚糖的精细结构信息,以便研究其功能,我们采用本实验室“拟规模化制备酵母甘露聚糖新工艺”,从废啤酒酵母(工厂下脚料)和市售鲜酵母细胞壁中制取了纯化的酵母甘露聚糖(mannan)。气相色谱法测定它们的糖组分和其相对含量,并且测定和比较分析酵母甘露聚糖与其组份糖的游离形式(甘露糖和葡萄糖)和酸解后的单体糖的可见—紫外吸收光谱和荧光发射光谱,和以He—Ne激光为激发光源的红外光谱。从中获得了:组份单糖聚合成甘露聚糖和多聚糖再分解成组份糖单体的光谱特征峰;和这些相关样品的光谱特征峰在聚合和分解过程中的变化与相应糖的细微结构变化的相关光谱信息。这些糖结构光谱特征相关信息为我们制备新型分子载体——甘露聚糖的聚合物(polymannan)和其功能研究提供了研究基础。  相似文献   

3.
目的:为了解酵母甘露聚糖对小鼠辐射损伤的保护作用。方法:60 Co γ射线以82 Gy 照射 60 只小鼠,雌雄各半。其中 30 只在辐照前 10 分钟腹腔注射 400m g M an/kg,另 30 只注射生理盐水。结果:从比较研究项目:鼠的存活率,成活天数;40 天体重的动态变化;外同血 W B C、 R B C及 P L T 及脾指数等的数值差异上,均显示酸母甘露聚糖对60 Co γ射线辐射损伤有保护作用。同时也发现该保护作用存在性别敏感性差异。结论:酵母甘露聚糖是一种比较好的辐射防护剂;酵母甘露聚糖对雄性鼠辐射损伤的保护作用显著,有统计学意义( P< 001)。  相似文献   

4.
本文采用多种化学方法与核磁共振(NMR)相结合确定甘露聚糖SP_1的结构。高碘酸盐氧化和甲基化衍生物的色-质联机分析(G.C.-M.S.)表明SP_1含有M-~1,-~2 M-~1,和-~6 M-~1*四种糖残基。部分酸水解和乙酰解证明SP_1的主链是1→6连接,侧链是1→2连接;其中长侧链有两个残基,短侧链只有一个残基。SP_1的~1H谱在H-1区出现四个较强和一个较弱的α型氢信号,~(13)C谱在C-1区出现三个较强的峰。它们的分布与化学方法所确定的结构基本一致。  相似文献   

5.
目的:为了解酵母甘露聚糖对小鼠辐射损伤的保护作用。方法:60Coγ-射线以8.2Gy照射60只小鼠,雌雄各半,其中30只在辐照前10分钟腹腔注400mgMan/kg,另30只注射生理盐水。结果:从比较研究项目,鼠的存活率,成活天数;40天体重的动态变化;外同血WBC、RBC及PLT及脾指数等的数值差异上,均显示酸母甘露聚糖对^60Coγ-射线辐射损伤有保护作用,同时也发现该保护作用存在性别2敏感性  相似文献   

6.
槐种子发育中胚乳细胞半乳甘露聚糖积累的研究   总被引:2,自引:0,他引:2  
槐 ( Sophora japonica L.)开花约 60 d至种子成熟 ,为胚乳半乳甘露聚糖积累期。用组织化学方法 ,对储藏于胚乳细胞壁上的半乳甘露聚糖的形成积累进行了观察 ,结果表明 ,半乳甘露聚糖最先在邻近胚的胚乳细胞的粗面内质网的囊泡腔内形成 ,并通过细胞质膜分泌至细胞壁周围。此后 ,半乳甘露聚糖的积累逐渐向种皮方向扩展 ,及至种子成熟时 ,除糊粉层外 ,所有胚乳细胞几乎全由多糖所填充。此外 ,对半乳甘露聚糖发生部位及其积累过程的消长变化进行了讨论  相似文献   

7.
从安络小皮伞水溶性多糖中分离纯化得一甘露聚糖FP1。分子量约为24万。经红外光谱、+H-NMR谱和亲和层析指明为β-甘露聚糖。结构分析采用高碘酸氧化、Smith降解、完全甲基化GC、GC—MS与13C—NMR分析,分子的主链是芦β-D-(1→6)连接的甘露糖,支链为β-(1→3),β(1→2)甘露糖,分别连接在主链的O-3和。O-2上。  相似文献   

8.
从安络小皮伞水溶性多糖中分离纯化得一甘露聚糖 FP_1。分子量约为24万。经红外光谱、~+H-NMR 谱和亲和层析指明为β-甘露聚糖。结构分析采用高碘酸氧化、Smith 降解、完全甲基化 GC、GC-MS 与~(13)C-NMR 分析,分子的主链是β-D-(1→6)连接的甘露糖,支链为β-(1→3),β(1→2)甘露糖,分别连接在主链的 O-3和 O-2上。  相似文献   

9.
【目的】建立分离、纯化分枝杆菌脂聚糖的方法,初步比较分析不同菌株来源的脂阿拉伯甘露聚糖(Lipoarabinomannan,LAM)和脂甘露聚糖(Lipomannan,LM)的结构差异及研究脂聚糖刺激对巨噬细胞环氧合酶-2(Cyclooxygenase-2,COX-2)蛋白表达的影响。【方法】应用Triton X-114液相法提取脂聚糖,电洗脱法分离纯化,基质辅助激光解析电离串联飞行时间质谱(MALDI-TOF/TOF-MS)进行分子量鉴定;基于特异性识别非还原性末端α-D-甘露糖基的刀豆球蛋白(Concanavalin A,Con A)分析新诺分枝杆菌JDM601、结核分枝杆菌H37Rv标准株和耻垢分枝杆菌mc2155脂聚糖的结构差异;进一步用Western blot检测脂聚糖刺激的RAW 264.7巨噬细胞COX-2蛋白的表达。【结果】通过电洗脱法成功纯化出3种菌株脂聚糖;MALDI-TOF/TOF-MS鉴定发现,分子量从小到大依次为新诺分枝杆菌JDM601、耻垢分枝杆菌mc2155和结核分枝杆菌H37Rv来源的脂聚糖。Western blot显示,Con A能与结核分枝杆菌H37Rv标准株来源的LAM相互作用,而不能与新诺分枝杆菌JDM601和耻垢分枝杆菌来源的LAM相互作用;并且发现Con A与新诺分枝杆菌JDM601来源的LM有很强的反应,然而与其余两种来源的LM反应很弱。3种菌株来源的脂聚糖均能刺激RAW 264.7巨噬细胞COX-2蛋白的表达。【结论】首次成功对来源于中国临床分枝杆菌分离株的脂聚糖进行了分离纯化,初步探讨了不同菌株来源分枝杆菌脂聚糖的结构差异,并表明LAM和LM均能刺激巨噬细胞诱导COX-2蛋白的表达,为进一步研究其对宿主的毒力和免疫机制奠定了基础。  相似文献   

10.
目的探讨假丝酵母菌甘露聚糖抗原和假丝酵母菌IgG/IgM抗体、曲霉半乳甘露聚糖抗原和烟曲霉IgG抗体在侵袭性真菌病早期临床诊断中的应用价值。方法收集已确诊侵袭性假丝酵母菌病患者18例,侵袭性烟曲霉病患者6例,单纯细菌感染患者20例,浅部真菌感染患者20例,健康体检者(正常对照组)20例,通过酶联免疫吸附法(ELISA)检测患者血清甘露聚糖和假丝酵母菌IgG/IgM抗体以及曲霉半乳甘露聚糖抗原和烟曲霉IgG抗体浓度,计算各指标的灵敏度、特异度、阳性预测值、阴性预测值和受试者工作特征(ROC)曲线下面积。结果甘露聚糖抗原和假丝酵母菌IgG/IgM抗体联合测定的敏感度为66.7%,特异度为83.3%,阴性预测值为100.0%,阳性预测值为85.7%,ROC曲线下面积为0.992(95%CI:0.974~1.000);半乳甘露聚糖抗原和烟曲霉IgG抗体联合测定的敏感度为66.7%,特异度为95.0%,阴性预测值为98.2%,阳性预测值为100.0%,ROC曲线下面积为0.978(95%CI:0.934~1.000)。结论甘露聚糖抗原和假丝酵母菌IgG/IgM抗体、半乳甘露聚糖抗原和烟曲霉IgG抗体联合检测对深部真菌感染的早期诊断具有重要意义。  相似文献   

11.
We prepared two kinds of sulfated silk fibroins, SclFib30 and SclFib31, which contain different amounts of sulfate. These sulfated silk fibroins have anti-HIV-1 activity in vitro, apparently due to interference with the adsorption of virus particles to CD4+ cells, and completely blocked virus binding to the cells at a concentration of 100 μg/ml. Sulfated fibroins also abolished cell-to-cell infection-induced syncytium formation upon cocultivation of MOLT-4 and MOLT-4/HIV-1IIIB cells, suggesting that they would interfere with gp120 and prevent the formation of gp120/CD4 complex. Silk is used in biomaterials such as surgical sutures and is believed to be a safe material for humans. In accordance with low anticoagulant activity and high anti-HIV-1 activity against both X4 HIV-1 and R5 HIV-1 strains, sulfated silk fibroins have potential as antiviral material such for a vaginal anti-HIV formulation.  相似文献   

12.
Sulfated N-linked carbohydrate chains in porcine thyroglobulin   总被引:3,自引:0,他引:3  
N-linked carbohydrate chains of porcine thyroglobulin were released by the hydrazinolysis procedure. The resulting mixture of oligosaccharide-alditols was fractionated by high-voltage paper electrophoresis, the acidic fractions were further separated by high-performance liquid chromatography on Lichrosorb-NH2, and analyzed by 500-MHz 1H-NMR spectroscopy and, partially, by permethylation analysis. Of the acidic oligosaccharide-alditols, the following sulfated carbohydrate chains could be identified: NeuAc alpha 2----6Gal beta 1----4GlcNAc beta 1----2Man alpha 1----3[(SO3Na----3)Gal beta 1----4GlcNAc beta1----2-Mana alpha 1----6]Man beta 1----4GlcNAc beta 1----4[Fuc alpha 1----6]GlcNAc-ol and NeuAc alpha 2----6Gal beta 1----4(SO3Na----)0-1 GlcNAc beta 1----2-Man alpha 1----3[NeuAc alpha 2----6Gal beta 1----4(SO3Na----6)1-0GlcNAc beta 1----2Man alpha 1----6]Man beta 1----4GlcNAc beta 1----4[Fuc alpha 1----6]GlcNAc- ol. The sulfated structural elements for porcine thyroglobulin form novel details of N-linked carbohydrate chains. They contribute to the fine structure of these oligosaccharides and are another type of expression of microheterogeneity.  相似文献   

13.
We prepared two kinds of sulfated silk fibroins, SclFib30 and SclFib31, which contain different amounts of sulfate. These sulfated silk fibroins have anti-HIV-1 activity in vitro, apparently due to interference with the adsorption of virus particles to CD4+ cells, and completely blocked virus binding to the cells at a concentration of 100 microg/ml. Sulfated fibroins also abolished cell-to-cell infection-induced syncytium formation upon cocultivation of MOLT-4 and MOLT-4/HIV-IIIB cells, suggesting that they would interfere with gp120 and prevent the formation of gp120/CD4 complex. Silk is used in biomaterials such as surgical sutures and is believed to be a safe material for humans. In accordance with low anticoagulant activity and high anti-HIV-1 activity against both X4 HIV-1 and R5 HIV-1 strains, sulfated silk fibroins have potential as antiviral material such for a vaginal anti-HIV formulation.  相似文献   

14.
Recently, we have demonstrated that T30695, a G-tetrad-forming oligonucleotide, is a potent inhibitor of human immunodeficiency virus, type I (HIV-1) integrase and the K(+)-induced loop folding of T30695 plays a key role in the inhibition of HIV-1 integrase (Jing, N., and Hogan, M. E. (1998) J. Biol. Chem. 273, 34992-34999). Here we have modified T30695 by introducing a hydrophobic bulky group, propynyl dU, or a positively charged group, 5-amino dU, into the bases of T residues of the loops, and by substitution of the T-G loops by T-T loops. Physical measurements have demonstrated that the substitution of propynyl dU or 5-amino dU for T in the T residues of the loops did not alter the structure of T30695, and these derivatives also formed an intramolecular G-quartet structure, which is an essential requirement for anti-HIV activity. Measured IC(50) and EC(50) values show that these substitutions did not induce an apparent decrease in the ability to inhibit HIV-1 integrase activity and in the inhibition of HIV-1 replication in cell culture. However, the substitution of T-T loops for T-G loops induced a substantial decrease in both thermal stability and anti-HIV activity. The data analysis of T30695 and the 21 derivatives shows a significant, functional correlation between thermal stability of the G-tetrad structure and the capacity to inhibit HIV-1 integrase activity and between thermal stability of the G-tetrad structure and the capacity to inhibit HIV-1 replication, as assessed with the virus strains HIV-1 RF, IIIB, and MN in cell culture. This relationship between thermostability and activity provides a basis for improving the efficacy of these compounds to inhibit HIV-1 integrase activity and HIV-1 replication in cell culture.  相似文献   

15.
Tyrosine sulfation of the amino terminus of CCR5 facilitates HIV-1 entry   总被引:23,自引:0,他引:23  
Chemokine receptors and related seven-transmembrane-segment (7TMS) receptors serve as coreceptors for entry of human and simian immunodeficiency viruses (HIV-1, HIV-2, and SIV) into target cells. Each of these otherwise diverse coreceptors contains an N-terminal region that is acidic and tyrosine rich. Here, we show that the chemokine receptor CCR5, a principal HIV-1 coreceptor, is posttranslationally modified by O-linked glycosylation and by sulfation of its N-terminal tyrosines. Sulfated tyrosines contribute to the binding of CCR5 to MIP-1 alpha, MIP-1 beta, and HIV-1 gp120/CD4 complexes and to the ability of HIV-1 to enter cells expressing CCR5 and CD4. CXCR4, another important HIV-1 coreceptor, is also sulfated. Tyrosine sulfation may contribute to the natural function of many 7TMS receptors and may be a modification common to primate immunodeficiency virus coreceptors.  相似文献   

16.
This study is to synthesize sulfated Angelica polysaccharides (APSs) and investigate the activity of one of the sulfated derivatives APS-1 on murine leukemia virus in vivo. Six sulfated derivatives with degree of sulfation ranging from 0.68 to 1.91 were obtained. And the virus replication was inhibited by APS-1 at the dose of 10 and 30 mg/kg (26% and 30% inhibition respectively). Furthermore, both the percentage of CD4(+) cells and CD4(+)/CD8(+) ratio in peripheral blood cells were significantly enhanced by APS-1 at 3-30 mg/kg. In addition, the reduced thymus/body weight index by murine leukemia virus infection was increased by ASP-1 in a dose dependent manner. These results suggest that APS-1 could not only inhibit virus replication, but also improve the immune function. APS-1 may be a potential new and better antiviral drug.  相似文献   

17.
Luteinizing hormone (LH), follicle-stimulating hormone (FSH) and thyroid-stimulating hormone (TSH) from pituitary and chorionic gonadotropin (CG) from placenta are a family of closely related glycoproteins. Each hormone is a heterodimer, consisting of an alpha- and a beta-subunit. Within an animal species, the alpha-subunits of all four glyco-protein hormones have an identical amino acid sequence, whereas each beta-subunit is distinct and confers hormone-specific features to the heterodimer. LH and FSH are synthesized within the same cell, the gonadotroph of the anterior pituitary, but are predominantly stored in separate secretory granules. We have characterized the asparagine-linked oligosaccharides on bovine, ovine and human LH, FSH and TSH. The various pituitary hormones were found to contain unique sulfated oligosaccharides with the terminal sequence SO4-4GalNAc beta 1----4GlcNAc beta 1----2Man alpha, sialylated oligosaccharides with the terminal sequence SA alpha Gal beta GlcNAc beta Man alpha, or both sulfated and sialylated structures. Despite synthesis of LH and FSH in the same pituitary cell, sulfated oligosaccharides predominate on LH while sialylated oligosaccharides predominate on FSH for all three animal species. We have examined the reactions leading to synthesis of the sulfated oligosaccharides to determine which steps are hormone specific. The sulfotransferase is oligosaccharide specific, requiring only the sequence GalNAc beta 1----4GlcNAc beta 1----2Man alpha. In contrast, the GalNAc-transferase appears to be protein specific, accounting for the preferential addition of GalNAc to LH, TSH, and free (uncombined) alpha-subunits compared with FSH and other pituitary glycoproteins. The predominance of sulfated oligosaccharide structures on LH may account for sorting of LH and FSH into separate secretory granules. Differences in sulfation and sialylation of LH, FSH and TSH may also play a role in the regulation of hormone bioactivity.  相似文献   

18.
19.
Japanese encephalitis virus (JEV), a neurotropic flavivirus, is one of the major causes of acute encephalitis in humans. After infection, inflammatory reactions and neurological diseases often develop. Still there are no effective drugs available against virus infection. Recently, extracts of algae have been shown to possess a broad range of biological activities including antivirus activity. In this study, we identified that the sulfated polysaccharide extracts from Ulva lactuca can inhibit JEV infection in Vero cells. Mechanistic studies further revealed that the Ulva sulfated polysaccharide extracts can block virus adsorption and thus make the virus unable to enter cells. The Ulva sulfated polysaccharide extracts also effectively decrease the production of pro-inflammatory cytokines in the JEV-infected primary mixed glia cells. In an animal study, the JEV-infected C3H/HeN mice appeared to have neurobehavioral abnormalities on the fifth day and died on the seventh day post infection. However, the JEV-infected mice pretreated with the Ulva sulfated polysaccharide extracts can delay the onset of hind limb paralysis and thereby prevent mice from death.  相似文献   

20.
Porcine heparin, whale heparin, and a solvolyzed porcine heparin were deaminated, and sulfated oligosaccharides, compounds 3f, 4f, 3s, 4s, 5, 6, 7s, 10, 11f, 11s, and 13 were isolated from the deamination products by Dowex 1 x 2 (Cl- form) column chromatography and high voltage paper electrophoresis and/or gel filtration on Sephadex G-25. Based on the results of chemical, 1H and 13C NMR spectral analyses, and of Smith degradation, together with previous observations, the structures of these sulfated oligosaccharides are proposed to be as follows: compound 3f, IdUA(2S)alpha 1 leads to GlcNAc alpha 1 leads to 4GlcUA; compound 4f, IdUA alpha 1 leads to 4GlcNAc(6S) alpha 1 leads to 4GlcUA; compound 3s, IdUA(2S) alpha 1 leads to 4GlcNAc alpha 1 leads to 4 GlcUA beta 1 leads to 4a Man; compound 4s, IdUA alpha 1 leads to 4Glc NAc(6S) alpha 1 leads to 4 GlcUA beta 1 leads to 4aMan; compound 5, IdUA(2S) alpha 1 leads to 4aMan; compound 6, GlcUA beta 1 leads to aMan(6S); compound 7s, IdUA alpha 1 leads to 4aMan(6S); compound 10, IdUA(2S)alpha 1 leads 4GlcNAc(6S)alpha 1 leads to 4 GlcUA beta 1 leads to 4aMan; compound 11f, IdUA(2S) alpha 1 leads 4GlcNAc alpha 1 leads to 4GlcUA beta 1 leads to 4a Man (6S); compound 11s, IdUA alpha 1 leads to GlcNAc(6S) alpha 1 leads to 4GlcUA beta 1 leads to 4aMan(6S); compound 13, IdUA(2S) alpha 1 leads to 4aMan(6S). For ths sulfated disaccharides, the same results as those reported in our previous papers were obtained. On the other hand, the proportion of total sulfated tri- and tetrasaccharides from whale heparin was 1.9 times higher than that from porcine heparine, reflecting a higher content of GlcNAc in the former. Also, the yields of compound 11s from these two heparins were comparable to their anticoagulant activities. In addition, certain 2-O-sulfates on IdUA flanked with GlcNS(6X) (X=H or S) in the heparin molecule are suggested to be important for the activity.  相似文献   

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