Summary

表达,分离,纯化可溶性和不溶性蛋白质生物素对神经组织再生

Published: January 22, 2014
doi:

Summary

开发biotinylatable融合蛋白具有在研究各个领域的许多潜在的应用。重组蛋白质工程是直线前进的过程,是符合成本效益的,提供定制设计的蛋白质的产量高。

Abstract

重组蛋白质工程已使用大肠杆菌(大肠杆菌)表达系统今天近40年,和E。大肠杆菌仍然是最广泛使用的宿主生物体。该系统的灵活性允许添加部分,例如生物素标记(链亲和素相互作用),以及较大的功能性蛋白,如绿色荧光蛋白或樱桃红蛋白。此外,非天然氨基酸,如金属离子螯合剂,唯一的反应性官能团,光谱探针和分子赋予的翻译后修饰的融合,使更好地操纵蛋白质性质和功能性的。因此这种方法创建自定义的融合蛋白,提供用于研究各个领域的显著效用。更具体地,biotinylatable蛋白质序列已被纳入,因为生物素与亲和素和链亲和素之间的高亲和力相互作用的成许多靶蛋白。这除了有辅助提高检测标签蛋白的纯化,以及开辟道路的二次应用,如细胞分选。因此,生物素标记的分子表现出生物产业和生物医学领域的增加和广泛的影响。对于我们的研究目的我们设计含神经生长因子(NGF)和semaphorin3A(SEMA3A)功能区的重组生物素标记的融合蛋白。我们以前曾报道了这些生物素化的融合蛋白,以及与其他活性蛋白的序列,可以被拴在生物材料用于组织工程和再生的目的。该协议概述了工程biotinylatable蛋白质的基本知识在毫克的规模,利用T7 lac启动诱导型载体和E。大肠杆菌表达宿主,从改造规模和纯化启动。

Introduction

蛋白质覆盖很宽范围的生物分子,负责许多生物学功能,最终导致适当的组织形成和组织。这些分子引发数千信令控制的上调和/或下调的基因和其他蛋白质的通路,维持人体内部平衡。单个蛋白的干扰影响的信号,这样的整个网络,从而导致破坏性的病症或疾病的发作。在实验室工程个别蛋白质可为打击这些不良影响一个解决方案,并提供了一​​种替代小分子药物。在1977中,编码14个氨基酸的生长激素释放抑制因子序列的基因是用大肠杆菌产生的第一个工程化多肽之一大肠杆菌 1。在1979年后不久,胰岛素克隆在质粒pBR322,转化,表达和纯化2。此后,重组蛋白已扩大其影响力,水库的多个字段目录操作搜索,如生物材料,药物释放,组织工程,生物制药,农业,工业酶制剂,生物燃料 (综述见参考文献3-8)。这主要是由于通用性通过加入特定应用化学部分或蛋白质序列为目的,包括该技术提供,但不限于,靶蛋白的识别,稳定和纯化。

通过重组DNA技术,重组蛋白可表达在多种真核和原核宿主系统,包括哺乳动物,植物,昆虫,酵母,真菌或细菌。每个主机提供了不同的优点,通常最好的系统是基于蛋白质的功能,收率,稳定性,整体成本,而且可扩展性来确定。细菌细胞往往缺乏真核宿主提供( 糖基化,二硫键桥接电子翻译后修饰机制 TC)5。其结果是,哺乳动物和昆虫系统通常导致更好的真核生物蛋白的兼容性和表达,但是这些主机通常更昂贵和费时9。因此,E.大肠杆菌为宿主的青睐我们的表达系统,因为细胞在廉价的生长条件迅速扩大和遗传表达机制很好地理解5,9。此外,此系统很容易按比例放大用于生产目的和结果在功能性蛋白,尽管缺乏翻译后修饰10。 大肠杆菌大肠杆菌 K12菌株选择在本协议中的克隆,因为这株提供了基于高转化效率优异的质粒产量。此外,一个E。大肠杆菌 BL21菌株被用于表达,因为这样的宿主菌株含有T7 RNA聚合酶基因,它提供受控的蛋白表达和稳定性11。

帐篷“>后宿主的选择,还必须注意在选择理想的表达载体中,以方便选择和控制蛋白质表达的影响。合成重组蛋白开始与下的噬菌体T7的转录和翻译信号的方向克隆的靶DNA序列,并表达诱导在含有T7 RNA聚合酶基因12的染色体拷贝的宿主细胞,这些载体中,从质粒载体pBR322衍生的(综述见参考文献13),被紧紧地由Studier和同事14最初开发的T7启动子控制并提供额外的通过包含lac操纵子和lac阻遏(LAC1)的控制15,16,对于重组蛋白质工程,该表达系统提供了通过将不同的目标DNA序列来调整所需要的蛋白质的特定氨基酸序列,或创建融合蛋白的能力由结合域S来自单一的蛋白质。此外,某些载体系列包括肽标签的修改被放置在N或C末端。我们的设计目的,组氨酸(His)标签加入到DNA靶序列进行纯化和一个15个氨基酸的序列biotinylatable被列入对生物素17,18。在这个协议中含有一个氨苄青霉素抗性基因的质粒,被选来进行我们的biotinylatable融合蛋白序列。表达是通过T7 lac启动子控制的该向量,并且很容易引起与异丙基-β-D-1-硫代半乳糖苷(IPTG)。

测试表达式(小规模培养物)被用于确定目标蛋白,它可以表示在任一的可溶性或不溶性形式配制的纯化程序的存在和溶解度。细菌细胞内的表达可溶性蛋白质会发生自发折叠,以保持其天然结构19。通常情况下,原生结构在热力学上是有利的。在许多情况下的主机的代谢活性,不利于目标蛋白,放置应力,导致不溶性的蛋白质的生产和不溶性蛋白质聚集体组成包涵体的形成系统。因而靶蛋白变性,使它们通常无生物活性20。两个测试表达式被按比例增加,并且分离步骤是将靶蛋白的溶解度来确定。一个额外的复性或再折叠步骤是必需的不溶性蛋白质。将所得的重组蛋白可以通过尺寸排阻色谱法进一步纯化。

在内部重组蛋白的生产提供了商业产品的成本优势,因为目标蛋白的毫克就可以每升主文化的隔离。大部分所需的设备可在一个典型的生物或化学实验室。蛋白质工程允许创建自定义的融合蛋白与添加的功能性,并不总是市售的。 图1描述了涉及工程重组蛋白的主要程序。用该表达系统,我们已经创建了许多biotinylatable蛋白质,如γ-干扰素,血小板衍生生长因子和骨形态发生蛋白21-23,但是我们将集中于两种蛋白质,我们设计的轴突导向,NGF(29 kDa的)和SEMA3A(91 kDa的)10(综述见参考图24)。生物素是一种常用的技术鉴定,固定化,并利用公知的生物素-链霉亲和相互作用25-27标记的蛋白质的分离。生物物理探针28,29,生物传感器30,和量子点31顷的,利用生物素-亲和共轭用K的D 10 -15米27的顺序上的高亲和力系统的一些例子。 大肠杆菌大肠杆菌生物锡连接酶BirA的,辅助的共价连接的生物素的生物素中发现的赖氨酸侧链的标签序列18,32。圈养生物素材料和生物分子产生了持续给药生长因子对细胞的多种组织工程应用21,33-35。因此,这些工程定制设计biotinylatable蛋白是一种功能强大的工具,它可以超越多的研究兴趣。

Protocol

1。目标蛋白的设计利用国家生物技术信息中心网站(http://www.ncbi.nlm.nih.gov/)获得获得目标蛋白考虑到利息和任何剪接变异体物种的氨基酸序列。选择对应的蛋白质所关注的活性区域的氨基酸序列。 注意:对于SEMA3A,氨基酸21-747被选中。融合蛋白在设计时,其中芽孢杆菌RNA,氨基酸1-90的顺序,加入NGF的氨基酸122-241神经生长因子。 到N-末端添加如下序列:6X-His标签…

Representative Results

克隆与表达测试 当被适当地进行化学镀,单个孤立的菌落形成,以增加拔除克隆转化的细菌细胞( 图2A)的机会。然而,如果太多的细胞铺板,将板温育时间过长,在37℃或转化是有问题的,菌落可以覆盖琼脂平板上或形成细胞的更大的聚集体( 图2B和2C)。在测试过程中表达,NGF和SEMA3A首次诱导4小时,在37℃和SDS-PAGE?…

Discussion

重组蛋白质工程是一个非常强大的技术,跨越许多学科。它是符合成本效益的,可调整的和相对简单的程序,从而允许生产定制设计的蛋白质的产量高。要注意,在设计和表达靶蛋白并不总是直截了当是很重要的。基础表达和重组蛋白的稳定性依赖于向量,E的具体选择大肠杆菌细胞株,肽标签添加和栽 ​​培参数。我们的具体设计标准采用完善的大肠杆菌大肠杆菌菌株的蛋?…

Divulgations

The authors have nothing to disclose.

Acknowledgements

作者要感谢阿克伦大学为支持这项工作的经费。

Materials

1,4-dithio–DL-threitol, DTT, 99.5% Chem-Impex International 127 100 g
2-Hydroxyethylmercaptan β-Mercaptoethanol Chem-Impex International 642 250 ml
Acetic acid, glacial EMD AX0073-9 2.5 L
Agar Bioshop AGR001.500 500 g
Ampicillin sodium salt  Sigma-Aldrich A9518 25 g
Antifoam 204 Sigma-Aldrich A6426 500 g
Barstar-NGF pET-21a(+) GenScript USA Inc. 4 µg
BL21(DE3) Competent Cells Novagen 69450 1 ml; Expression Host
Bradford reagent Sigma-Aldrich B6916 500 ml
BugBuster Novagen 70922-3 100 ml
Gel filtration standard Bio-Rad 151-1901 6 vials
Glycerol Bioshop GLY001.1 1 L
Guanidine hydrodioride amioformamidine hydrochloride Chem-Impex International 152 1 kg
His-Pur Ni-NTA Resin Thermo Scientific 88222 100 ml
Hydrochloric acid EMD  HX0603-3 2.5 L
Imidazole  Chem-Impex International 418 250 g
IPTG Chem-Impex International 194 100 g
Laemmli sample buffer Bio-Rad 161-0737 30 ml
Lauryl sulfate sodium salt, Sodium dodecyl surface Chem-Impex International 270 500 g
LB Broth   Sigma-Aldrich L3022 1 kg
NovaBlue Competent Cells Novagen 69825 1 ml; Cloning Host
Phosphate buffered saline Sigma-Aldrich P5368-10PAK 10 pack
Potassium Chloride Chem-Impex International 01247 1 kg
Sema3A-pET-21a(+) GenScript USA Inc. 4 µg
SimplyBlue SafeStain Invitrogen LC6060 1 L
Sodium chloride Sigma-Aldrich S5886-1KG 1 kg
Sodium hydroxide Fisher Scientific S318-500 500 g
Sodium phosphate diabasic Sigma-Aldrich S5136-500G 500 g
Sodium phosphate monobasic Sigma-Aldrich S5011 500 g
Terrific Broth Bioshop TER409.5 5 kg
Tetracycline hydrochloride Chem-Impex International 667 25 g
Tris/Glycine/SDS Buffer, 10X Bio-Rad 1610732 1 L
Trizma Base Sigma-Aldrich T1503 1 kg
Tryptone, pancreatic EMD 1.07213.1000 1 kg
Yeast extract, granulated EMD 1.03753.0500 500 g
Name of Kits/ Equipment Company Catalog Number Comments/Description
 ÄKTApurifier10 GE Healthcare 28-4062-64  Includes kits and accessories
Benchtop Orbital Shaker Thermo Scientific SHKE4000 MAXQ 4000
BirA500 Avidity BirA500 Enzyme comes with reaction buffers and biotin solution
Dialysis Casette Thermo Scientific 66380 Slide-A-Lyzer (Extra Strength)
Dialysis Tubing Spectrum Laboratories  132127, 132129 MWCO: 25,000 and 50,000
Flow Diversion Valve FV-923 GE Healthcare 11-0011-70
FluoReporter Biotin Quantification Assay Kit Invitrogen 1094598
Frac-950 Tube Racks, Rack C GE Healthcare 18-6083-13
Fraction Collector Frac-950 GE Healthcare 18-6083-00 Includes kits and accessories
Heated/Refrigerated Circulator  VWR 13271-102 Model 1156D
Heating Oven FD Series Binder Model FD 115
HiLoad 16/60 Superdex 200 pg GE Healthcare 17-1069-01 Discontinued–Replacement Product: HiLoad 16/600 Superdex 200 pg
J-26 XPI Avanti Centrifuge Beckman Coulter 393126
JA 25.50 Rotor Beckman Coulter 363055
JLA 8.1 Rotor Beckman Coulter 969329 Includes 1 L polyporpylene bottles
JS 5.3 Rotor Beckman Coulter 368690
Laminar Flow Hood Themo Scientific 1849 Forma 1800 Series Clean Bench
Microplate Reader TECAN infinite M200
Mini-PROTEAN Tetra Cell Bio-Rad 165-8004 4-gel vertical electrophoresis system
Mini-PROTEAN TGX Precast Gels Bio-Rad 456-9036 Any kDa, 15-well comb
Ni-NTA Column Bio-Rad 737-2512 49 ml volume ECONO-Column
Plasmid Miniprep Kit OMEGA bio-tek D6943-01
PowerPac HC Power Supply Bio-Rad 164-5052 250 V, 3 A, 300 W
Round Bottom Polypropylene Copolymer Tubes VWR 3119-0050 50 ml tubes for JA 25.50 rotor
Spin-X UF Concentrators Corning 431488, 431483  20 and 6 ml; MWCO: 10,000 Da
Subcloning Service GenScript USA Inc. Protein Services
Ultrasonic Processor  Cole-Parmer 18910445A Model CV18
Vortex-Genie 2 Scientific Industries SI-0236 Model G560

References

  1. Itakura, K., et al. Expression in Escherichia coli of a chemically synthesized gene for the hormone somatostatin. Science. 198 (4321), 1056-1063 (1977).
  2. Goeddel, D. V., et al. Expression in Escherichia coli of chemically synthesized genes for human insulin. Proc. Natl. Acad. Sci. U.S.A. 76 (1), 106-110 (1979).
  3. Romano, N. H., Sengupta, D., Chung, C., Heilshorn, S. C. Protein-engineered biomaterials: nanoscale mimics of the extracellular matrix. Biochim. Biophys. Acta. 1810 (3), 339-349 (2011).
  4. Sengupta, D., Heilshorn, S. C. Protein-engineered biomaterials: highly tunable tissue engineering scaffolds. Tissue Eng. Part B Rev. 16 (3), 285-293 (2010).
  5. Kamionka, M. Engineering of therapeutic proteins production in Escherichia coli. Curr. Pharm. Biotechnol. 12 (2), 268-274 (2011).
  6. Rao, A. G. The outlook for protein engineering in crop improvement. Plant Physiol. 147 (1), 6-12 (2008).
  7. Wen, F., Nair, N. U., Zhao, H. Protein engineering in designing tailored enzymes and microorganisms for biofuels production. Curr. Opin. Biotechnol. 20 (4), 412-419 (2009).
  8. Singh, R. K., Tiwari, M. K., Singh, R., Lee, J. K. From protein engineering to immobilization: promising strategies for the upgrade of industrial enzymes. Int. J. Mol. Sci. 14 (1), 1232-1277 (2013).
  9. Bernaudat, F., et al. Heterologous expression of membrane proteins: choosing the appropriate host. PLoS One. 6 (12), (2011).
  10. McCormick, A. M., Wijekoon, A., Leipzig, N. D. Specific immobilization of biotinylated fusion proteins NGF and Sema3A utilizing a photo-cross-linkable diazirine compound for controlling neurite extension. Bioconjug. Chem. 24 (9), 1515-1526 (2013).
  11. Studier, F. W., Daegelen, P., Lenski, R. E., Maslov, S., Kim, J. F. Understanding the differences between genome sequences of Escherichia coli. B strains REL606 and BL21(DE3) and comparison of the E. coli B and K-12. 394 (4), 653-680 (2009).
  12. Merck KGaA, . . Novagen pET System Manual. , 1-63 (2011).
  13. Balbas, P., Bolivar, F. Back to basics: pBR322 and protein expression systems in E. coli. Methods Mol. Biol. 267, 77-90 (2004).
  14. Studier, F. W., Moffatt, B. A. Use of bacteriophage T7 RNA polymerase to direct selective high-level expression of cloned genes. J. Mol. Biol.. 189 (1), 113-130 (1986).
  15. Dubendorff, J. W., Studier, F. W. Controlling basal expression in an inducible T7 expression system by blocking the target T7 promoter with lac repressor. J. Mol. Biol. 219 (1), 45-59 (1991).
  16. Studier, F. W., Rosenberg, A. H., Dunn, J. J., Dubendorff, J. W. Use of T7 RNA polymerase to direct expression of cloned genes. Methods Enzymol. 185, 60-89 (1990).
  17. Tucker, J., Grisshammer, R. Purification of a rat neurotensin receptor expressed in Escherichia coli. Biochem. J.. 317, 891-899 (1996).
  18. Schatz, P. J. Use of peptide libraries to map the substrate specificity of a peptide-modifying enzyme: a 13 residue consensus peptide specifies biotinylation in Escherichia coli). Biotechnology. 11 (10), 1138-1143 (1993).
  19. Anfinsen, C. B. Principles that govern the folding of protein chains. Science. 181 (4096), 223-230 (1973).
  20. Villaverde, A., Carrio, M. M. Protein aggregation in recombinant bacteria: biological role of inclusion bodies. Biotechnol. Lett. 25 (17), 1385-1395 (2003).
  21. Leipzig, N. D., Wylie, R. G., Kim, H., Shoichet, M. S. Differentiation of neural stem cells in three-dimensional growth factor-immobilized chitosan hydrogel scaffolds. Biomaterials. 32 (1), 57-64 (2011).
  22. Tam, R. Y., Cooke, M. J., Shoichet, M. S. A covalently modified hydrogel blend of hyaluronan-methyl cellulose with peptides and growth factors influences neural stem/progenitor cell fate. J. Mater. Chem. 22, 19402-19411 (2012).
  23. Li, H., Wijekoon, A., Leipzig, N. D. 3D Differentiation of Neural Stem Cells in Macroporous Photopolymerizable Hydrogel Scaffolds. PLoS One. 7 (11), (2012).
  24. McCormick, A. M., Leipzig, N. D. Neural regenerative strategies incorporating biomolecular axon guidance signals. Ann. Biomed. Eng. 40 (3), 578-597 (2012).
  25. Kay, B. K., Thai, S., Volgina, V. V. High-throughput biotinylation of proteins. Methods Mol. Biol. 498, 185-196 (2009).
  26. Bayer, E. A., Wilchek, M. Protein biotinylation. Methods Enzymol. 184, 138-160 (1990).
  27. Weber, P. C., Ohlendorf, D. H., Wendoloski, J. J., Salemme, F. R. Structural origins of high-affinity biotin binding to streptavidin. Science. 243 (4887), 85-88 (1989).
  28. Chen, I., Ting, A. Y. Site-specific labeling of proteins with small molecules in live cells. Curr. Opin. Biotechnol. 16 (1), 35-40 (2005).
  29. Howarth, M., Ting, A. Y. Imaging proteins in live mammalian cells with biotin ligase and monovalent streptavidin. Nat. Protoc. 3 (3), 534-545 (2008).
  30. Hutsell, S. Q., Kimple, R. J., Siderovski, D. P., Willard, F. S., Kimple, A. J. High-affinity immobilization of proteins using biotin- and GST-based coupling strategies. Methods Mol. Biol. 627, 75-90 (2010).
  31. Marek, P., Senecal, K., Nida, D., Magnone, J., Senecal, A. Application of a biotin functionalized QD assay for determining available binding sites on electrospun nanofiber membrane. J. Nanobiotechnol. 9, 48 (2011).
  32. Cull, M. G., Schatz, P. J. Biotinylation of proteins in vivo and in vitro using small peptide tags. Methods Enzymol. 326, 430-440 (2000).
  33. Miller, R. E., Kopesky, P. W., Grodzinsky, A. J. Growth factor delivery through self-assembling peptide scaffolds. Clin. Orthop. Relat. Res. 469 (10), 2716-2724 (2011).
  34. Davis, M. E., Hsieh, P. C., Grodzinsky, A. J., Lee, R. T. Custom design of the cardiac microenvironment with biomaterials. Circ. Res. 97 (1), 8-15 (2005).
  35. Tokatlian, T., Shrum, C. T., Kadoya, W. M., Segura, T. Protease degradable tethers for controlled and cell-mediated release of nanoparticles in 2- and 3-dimensions. Biomaterials. 31 (31), 8072-8080 (2010).
  36. Gill, R. T., Valdes, J. J., Bentley, W. E. A comparative study of global stress gene regulation in response to overexpression of recombinant proteins in Escherichia coli. Metab. Eng. 2 (3), 178-189 (2000).
  37. Sivashanmugam, A., et al. Practical protocols for production of very high yields of recombinant proteins using Escherichia coli. Protein Sci. 18 (5), 936-948 (2009).
  38. Graslund, S., et al. Protein production and purification. Nat. Methods. 5 (2), 135-146 (2008).
  39. Marston, F. A. The purification of eukaryotic polypeptides synthesized in Escherichia coli. Biochem. J. 240 (1), 1-12 (1986).
  40. Sorensen, H. P., Mortensen, K. K. Soluble expression of recombinant proteins in the cytoplasm of Escherichia coli. Microb. Cell Fact. 4 (1), (2005).
  41. de Marco, A., Deuerling, E., Mogk, A., Tomoyasu, T., Bukau, B. Chaperone-based procedure to increase yields of soluble recombinant proteins produced in E. coli. BMC Biotechnol. 7, 32 (2007).
  42. de Groot, N. S., Ventura, S. Effect of temperature on protein quality in bacterial inclusion bodies. FEBS Lett. 580 (27), 6471-6476 (2006).
  43. Ventura, S., Villaverde, A. Protein quality in bacterial inclusion bodies. Trends Biotechnol. 24 (4), 179-185 (2006).
  44. Vera, A., Gonzalez-Montalban, N., Aris, A., Villaverde, A. The conformational quality of insoluble recombinant proteins is enhanced at low growth temperatures. Biotechnol. Bioeng. 96 (6), 1101-1106 (2007).
  45. Peternel, S., Komel, R. Isolation of biologically active nanomaterial (inclusion bodies) from bacterial cells. Microb. Cell Fact. 9, 66 (2010).
  46. Garcia-Fruitos, E. Inclusion bodies: a new concept. Microb. Cell Fact. 9. 9, 80 (2010).
  47. Li, Y., Sousa, R. Expression and purification of E. coli BirA biotin ligase for in vitro biotinylation. Protein Expr. Purif. 82 (1), 162-167 (2012).
check_url/fr/51295?article_type=t

Play Video

Citer Cet Article
McCormick, A. M., Jarmusik, N. A., Endrizzi, E. J., Leipzig, N. D. Expression, Isolation, and Purification of Soluble and Insoluble Biotinylated Proteins for Nerve Tissue Regeneration. J. Vis. Exp. (83), e51295, doi:10.3791/51295 (2014).

View Video