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1.
利用GAP启动子在毕赤酵母中组成型表达人鹅型溶菌酶2   总被引:1,自引:0,他引:1  
利用甘油醛三磷酸脱氢酶(glyceraldehydes-3-phosphatedehydrogenase,GAP)启动子在毕赤酵母中表达人鹅型溶菌酶2(human goose-type lysozyme 2,h LysG2),并在小试规模建立一套有效的重组hLysG2(recombinant h LysG2,rh LysG2)生产工艺流程。根据毕赤酵母密码子偏爱性设计并人工合成hLysG2基因,将其连接至pGAPZαA质粒中,构建重组表达质粒pGAPZαA-h LysG2。将重组表达载体线性化后电转化毕赤酵母GS115感受态细胞,通过Zeocin抗性筛选获取高拷贝重组菌株,并在5L生物反应器中进行发酵培养。发酵60h后发酵液上清酶活性达到最高,发酵液上清经SDS-PAGE及Western blot检测证实rh LysG2得到表达。与诱导型表达相比,组成型表达发酵时间缩短了48h,上清中rhLysG2总活性提高了23.8%;使用甲壳素亲和层析和分子筛层析对rhLysG2进行纯化后,每升发酵液上清可纯化到187.4mg重组蛋白,纯化产物纯度达99.0%以上;浊度测定法分析显示,在p H 5.6、30℃和0.1mol/L Na+的条件下,rhLysG2可达到最大酶活性13 500U/mg。利用GAP启动子在毕赤酵母中成功表达了高纯度和高活性的rh LysG2,避免了甲醇的使用,缩短了发酵时间,提高了蛋白产量,为将rhLysG2开发为新型抗耐药菌药物奠定了基础。  相似文献   

2.
原核重组表达的凡纳滨对虾(Litopenaeus vannamei)溶菌酶蛋白主要以包涵体形式存在, 经变性和复性处理后活性仍较差。研究将凡纳滨对虾溶菌酶基因(Lvlyz基因)克隆至毕赤酵母分泌型表达载体pPIC9K中, 电击转化毕赤酵母GS115细胞, 经组氨酸营养缺陷培养基筛选和PCR检测获得转化子。对其进行连续甲醇诱导表达, 利用SDS-PAGE和C端携带的6×His标签,对发酵液上清进行Western blot检测, 结果表明19.3 kD左右的条带即是重组表达的溶菌酶蛋白。用溶壁微球菌平板抑菌法鉴定表达产物具有较强的抑菌能力。研究首次利用毕赤酵母真核表达系统实现对虾溶菌酶基因的可溶性表达, 并且表达产物的活性良好。    相似文献   

3.
复合干扰素突变体在毕赤酵母中的表达、纯化及活性分析   总被引:1,自引:0,他引:1  
根据毕赤酵母密码子偏性合成了复合干扰素突变体基因 ,克隆至分泌型酵母表达载体pMEX9K ,将重组载体pMEX CIFNm用SacⅠ线性化后 ,转化毕赤酵母GS115 .转化子经诱导后 ,培养上清有抗病毒活性的蛋白产生 .经过离子交换 ,疏水层析 ,凝胶过滤三步层析纯化 ,得到了纯度大于95 %的重组复合干扰素突变体 ,经N端氨基酸序列分析表明 ,该蛋白N端序列与理论值一致 ,质谱测定分子量为 19 3kD ,与理论值一致 .用细胞病变抑制法测定其活性 ,并结合Lowry法蛋白定量计算其比活性为 6× 10 8IU mg ,与复合干扰素的比活相当 .  相似文献   

4.
将人可溶性晚期糖基化终产物受体(human soluble Receptor for advanced glycation end product,hsRAGE)cDNA插入巴斯德毕赤酵母组成型表达载体pGAPZαA,构建重组表达载体pGAPZαA-hsRAGE,并转化到毕赤酵母X-33中,利用含抗生素Zeocin的YPD平板筛选重组子。重组菌株在甘油醛-3-磷酸脱氢酶(GAP)启动子的调控作用下,进行组成型分泌表达,在发酵液中获得了相对分子质量约45 kD的重组蛋白。摇瓶发酵结果表明,在发酵温度30℃、pH6.0、发酵时间72 h时重组蛋白表达占发酵上清液总蛋白68.4%。Western blotting显示,重组蛋白能够被相应抗体所识别。纯化后的重组hsRAGE具有与AGEs相互结合的活性,并能够显著地抑制AGEs诱导的人血管内皮细胞系ECV-304细胞NF-κB信号通路中NF-κB/p65基因的表达。  相似文献   

5.
目的:在毕赤酵母中高效分泌表达与天然人载脂蛋白C-I具有相同结构和活性的重组人载脂蛋白C-I( rhApoC-I).方法:RT-PCR法自人肝组织调取编码人ApoC-I的cDNA,构建真核分泌型表达载体pPICZα/hApoC-I.重组质粒线性化后转化毕赤酵母感受态细胞,甲醇诱导表达,建立rhApoC-I的毕赤酵母表达体系.对rhApoC-I进行Western blot分析和体外活性研究.结果:经PCR法克隆的hApoC-I cDNA序列与GenBank登录序列一致.SDS-PAGE和Western blot分析均在分子量约6.6kDa出现特异性条带,2L发酵条件下表达量达到80mg/L.结论:首次在毕赤酵母菌中高效分泌表达rhApoC-I,并确定其具有抑制血小板衍生生长因子诱导的平滑肌细胞增殖的抑制作用,为进一步研究其结构与功能提供物质基础.  相似文献   

6.
LYZL4是本实验室克隆的一种c型人溶菌酶基因,根据毕赤酵母密码子偏爱性对LYZL4基因进行优化设计,优化后的基因克隆至具有乙醇氧化酶启动子(AOX1)的pPIC9K载体中。通过电转化方法整合到甲醇营养型毕赤酵母表达菌株GS115基因组上,再利用不同浓度梯度的G418抗性YPD固体培养基筛选高拷贝转化子,经摇瓶发酵后,其上清液在SDS-PAGE胶上14.4 kDa处出现明显的蛋白条带,该蛋白条带经质谱鉴定证实是人LYZL4蛋白。以人溶菌酶(164 071U/mg)作为标准品,使用艳红微球菌作为底物,通过比色法测定重组LYZL4溶菌酶蛋白的活性,结果显示重组人溶菌酶LYZL4蛋白具有明显的溶菌活性,其酶活力可达38893U/ml。  相似文献   

7.
依据已报道的地鳖虫成熟肽cDNA序列设计引物,通过RT-PCR法从地鳖虫(Eupolyphage sinensis Walker)中克隆得到675 bp地鳖虫纤溶活性蛋白 (fibrinolytic protein,EFP)成熟肽编码序列.将此片段克隆到表达载体pPICZα-A中,转化毕赤酵母GS115,甲醇诱导表达得到重组表达蛋白,经SDS-PAGE电泳和活性鉴定,表明重组EFP在毕赤酵母中均获得表达,重组表达蛋白相对分子质量为28.2 kD,表达产物分子质量与理论分子质量相符.重组蛋白在毕赤酵母中以分泌形式表达,具有纤溶活性.  相似文献   

8.
瑞氏木霉表达黑曲霉葡萄糖氧化酶   总被引:8,自引:0,他引:8  
利用高表达分泌纤维素酶的真菌瑞氏木霉表达重组的黑曲霉葡萄糖氧化酶。在大肠杆菌DH5α中构建瑞氏木霉纤维素酶CBHI启动子和CBHI信号肽基因黑曲霉葡萄糖氧化酶基因瑞氏木霉纤维素酶CBHI终止子构巢曲霉的甘油醛3磷酸脱氢酶启动子大肠杆菌抗潮霉素B磷酸转移酶基因构巢曲霉色氨酸C终止子pUC19(命名为pCBHGOD)质粒,线性化后用瑞氏木霉纤维素酶CBHI启动子和CBHI信号肽基因黑曲霉葡萄糖氧化酶基因瑞氏木霉纤维素酶CBHI终止子构巢曲霉的甘油醛3磷酸脱氢酶启动子大肠杆菌抗潮霉素B磷酸转移酶基因构巢曲霉色氨酸C终止子(命名为CBHGOD)核酸片段转化瑞氏木霉QM9414原生质体。用PCR扩增方法筛选出同源重组葡萄糖氧化酶基因的瑞士木霉突变株。用麦杆诱导瑞氏木霉突变株,生产黑曲霉葡萄糖氧化酶,Westernblot分析重组的葡萄糖氧化酶分子量与Sigma公司的天然黑曲霉葡萄糖氧化酶一致,生产的重组酶活性25umL,相当于Sigma公司葡萄糖氧化酶标准品的产量为0.5gL。瑞氏木霉可用于生产黑曲霉葡萄糖氧化酶。  相似文献   

9.
目的:用毕赤酵母表达系统表达重组人血小板衍生生长因子BB亚型(PDGF-BB)。方法:采用PT-PCR从人早幼粒白血病细胞系HL-60细胞中获得目的基因,克隆到表达载体p MEX9K中,质粒线性化后转化酵母表达菌株GS115,筛选后的酵母表达菌株经BMGY/BMMY培养基体系诱导表达后,通过疏水作用、离子交换、凝胶过滤纯化获得目的蛋白,采用SDS-PAGE、Western印迹、N端氨基酸序列和MTT增殖活性测定等方法检测目的蛋白性质及生物活性。结果:重组人PDGF-BB为分泌表达,表达量大于100 mg/L;经三步纯化,获得纯度高于95%且具有较高活性(5.0×105IU/mg)的目标蛋白。结论:利用毕赤酵母表达系统表达重组人PDGF-BB,表达产量高,成本低,工艺简单,易于工业化放大,有良好的市场前景。  相似文献   

10.
克隆并在酵母中表达两个不同N段序列长度的匍枝根霉△6-脂肪酸脱氢酶重组子,其中长序列的重组子LYRnD6D是从匍枝根霉中克隆的△6-脂肪酸脱氢酶基因,编码459个氨基酸,N端序列为MSTLDRQSIFTIKELESISQRIHDG-DEEAMKFIII;短序列重组子SYRnD6D是预测的匍枝根霉△6-脂肪酸脱氢酶基因的ORF序列,N端序列为MKFIIIDKKVY,编码430个氨基酸;两个重组子均具有△6-脂肪酸脱氢酶保守的组氨酸序列和HPGG序列,长序列的N端比短序列长29个氨基酸残基(MSTLDRQSIFTIKELESISQRIHDGDE-EA)。两个重组子在缺陷型酵母中均得到了的表达,产生了γ-亚麻酸。利用酶的相对活力比较两个重组子在同一温度下的稳定性,长序列重组子的酶在15℃下反应4h后相对活力仍有74%,而短序列酶的相对活力只有43%,所以长序列重组子酶在低温下比短序列酶稳定性高,是因为长序列多出的氨基酸序列增加了酶的稳定性。  相似文献   

11.
A new polynitro cage compound 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptcyclo [5.5.1.1(3,11).1(5,9)] pentadecane (NNNAHP) was designed in the present work. Its molecular structure was optimized at the B3LYP/6-31 G(d,p) level of density functional theory (DFT) and crystal structure was predicted using the Compass and Dreiding force fields and refined by DFT GGA-RPBE method. The obtained crystal structure of NNNAHP belongs to the P-1 space group and the lattice parameters are a = 9.99 ?, b = 10.78 ?, c = 9.99 ?, α = 90.01°, β = 120.01°, γ = 90.00°, and Z = 2, respectively. Based on the optimized crystal structure, the band gap, density of state, thermodynamic properties, infrared spectrum, strain energy, detonation characteristics, and thermal stability were predicted. Calculation results show that NNNAHP has detonation properties close to those of CL-20 and is a high energy density compound with moderate stability.  相似文献   

12.
The variation with age of the 18 trace element mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0–30 years was investigated by instrumental neutron activation analysis, inductively coupled plasma atomic emission spectrometry, and a quantitative morphometric analysis. Mean values ± standard error of the mean (M ± SΕΜ) for the mass fractions (in milligrams per kilogram wet tissue) of these trace elements in pre-puberty were: Al 28.5 ± 9.0, B 0.40 ± 0.11, Ba 1.48 ± 0.44, Br 10.5 ± 1.5, Ca 241 ± 30, Cl 3,203 ± 278, Cu 3.51 ± 0.89, Fe 33.7 ± 4.1, K 2,364 ± 145, Li 0.020 ± 0.004, Mg 153 ± 23, Mn 0.46 ± 0.06, Na 2,286 ± 130, P 1,391 ± 100, S 1,698 ± 132, Si 62 ± 11, Sr 0.38 ± 0.08, and Zn 27.6 ± 2.3. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Al 7.2 ± 1.4, B 0.21 ± 0.05, Ba 0.25 ± 0.06, Br 5.8 ± 1.0, Ca 433 ± 81, Cl 2,314 ± 201, Cu 1.77 ± 0.13, Fe 20.9 ± 1.6, K 2,585 ± 118, Li 0.0088 ± 0.0014, Mg 232 ± 27, Mn 0.34 ± 0.04, Na 1,875 ± 107, P 1,403 ± 98, S 1,673 ± 73, Si 22.2 ± 3.1, Sr 0.22 ± 0.03, and Zn 93.3 ± 8.9. Mean values (M ± SΕΜ) of percent volumes (%) of the stroma, epithelium and lumen in the prostate before puberty were 73.4 ± 2.6, 20.4 ± 1.7, and 4.45 ± 0.94, respectively, versus 46.5 ± 2.5, 38.5 ± 1.9, and 14.9 ± 1.2 during puberty and postpuberty. This work’s results confirm that the Zn mass fraction in prostate tissue is an androgen-dependent parameter. For the first time it has been demonstrated that the glandular lumen is a main pool of Ca, Mg, and Zn accumulation and that the stroma is a main pool of Al, B, Ba, Br, Cl, Cu, Fe, Mn, Na, and Si accumulation in the normal human prostate, for the age range 0–30 years. It was concluded that the Ca, Mg, and Zn binds tightly within the prostatic fluid, because the volume of glandular lumen reflects the volume of prostatic fluid.  相似文献   

13.
14.
The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs.  相似文献   

15.
The goal of this article was to establish reference ranges of the concentration of trace elements in human serum and to compare these results with those reported by other authors. We describe the sample preparation and measurement conditions that allow the rapid, precise, and accurate determination of Al, As, B, Be, Cd, Co, Cu, Fe, Li, Mn, Mo, Ni, Rb, Se, Sr, and Zn in human serum samples (n=110) by inductively coupled plasma-mass spectrometry (ICP-MS). Accuracy and precision were determined by analyzing three reconstituted reference serum samples by comparison with other methods and by the standard addition procedure. The advantages of the ICP-MS method include short time of analysis of the elements mentioned, low detection limit, high precision, and high accuracy. Disadventages include a high risk of contamination due to the presence of some of the elements of interest in the environment, the relatively delicate sample handling, and the high cost of the equipment.  相似文献   

16.
《Ibis》1894,36(3):447-460
  相似文献   

17.
Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons.  相似文献   

18.
This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues and body fluids. A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America, Australia, and New Zealand. This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world. It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different countries reflected some interesting associations for elements, such as Mn and Zn. Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as Cu, Fe, and Zn were not available. In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions, which sadly lack data of any kind at present.  相似文献   

19.
We report 19 new species records for the faunal list of Coleoptera in New Brunswick, Canada, six of which are new records for the Maritime provinces, and one of which is new Canadian record. We also provide the first recent records for five additional species in New Brunswick. One new species of Stenotrachelidae, Cephaloon ungulare LeConte, is added to the New Brunswick faunal list. Additional records are provided for Cephaloon lepturides Newman, as well the first recent record of Nematoplus collaris LeConte. Two species of Oedemeridae, Asclera puncticollis (Say) and Asclera ruficollis (Say), are newly reported for New Brunswick, and additional locality and bionomic data are provided for Calopus angustus LeConte and Ditylus caeruleus (Randall). The records of Ditylus caerulus are the first recent records for the province. Three species of Meloidae, Epicauta pestifera Werner, Lytta sayi LeConte, and Meloe augustcollis Say are reported the first time for New Brunswick; Epicauta pestifera is newly recorded in Canada. Lacconotus punctatus LeConte and the family Mycteridaeis newly recorded for New Brunswick. The first recent records of Borus unicolor Say (Boridae) are reported from the province. One new species of Pythidae, Pytho siedlitzi Blair, and the first recent records of Pytho niger Kirby are added to the faunal list of New Brunswick. Three species of Pyrochroidae are newly reported for the province, including Pedilus canaliculatus (LeConte) and Pedilus elegans (Hentz), which are new for the Maritime provinces. Five species of Anthicidae and the first recent record of Anthicus cervinus LaFerté-Sénectére are newly reported for New Brunswick. Anthicus melancholicus LaFerté-Sénectère, Sapintus pubescens (LaFerté-Sénectère), Notoxus bifasciatus (LeConte), and Stereopalpus rufipes Casey are new to the Maritime provinces faunal list. Ambyderus granularis (LeConte) is removed from the faunal list of the province. Three species of Aderidae, Vanonus huronicus Casey, Zonantes fasciatus (Melsheimer), and Zonantes pallidusWerner, are newly recorded for New Brunswick; Zonantes fasciatus and Vanonus huronicus are new for the Maritime provinces' faunal list. Collection data, bionomic data, and distribution maps are presented for all these species.  相似文献   

20.
Oral cancer is one of the main causes of cancer-related deaths in South-Asian countries. There are very limited treatment options available for oral cancer. Research endeavors focused on discovery and development of novel therapies for oral cancer, is necessary to control the ever rising oral cancer related mortalities. We mined the large pool of compounds from the publicly available compound databases, to identify potential therapeutic compounds for oral cancer. Over 84 million compounds were screened for the possible anti-cancer activity by custom build SVM classifier. The molecular targets of the predicted anti-cancer compounds were mined from reliable sources like experimental bioassays studies associated with the compound, and from protein-compound interaction databases. Therapeutic compounds from DrugBank, and a list of natural anti-cancer compounds derived from literature mining of published studies, were used for building partial least squares regression model. The regression model thus built, was used for the estimation of oral cancer specific weights based on the molecular targets. These weights were used to compute scores for screening the predicted anti-cancer compounds for their potential to treat oral cancer. The list of potential compounds was annotated with corresponding physicochemical properties, cancer specific bioactivity evidences, and literature evidences. In all, 288 compounds with the potential to treat oral cancer were identified in the current study. The majority of the compounds in this list are natural products, which are well-tolerated and have minimal side-effects compared to the synthetic counterparts. Some of the potential therapeutic compounds identified in the current study are resveratrol, nimbolide, lovastatin, bortezomib, vorinostat, berberine, pterostilbene, deguelin, andrographolide, and colchicine.  相似文献   

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