Summary

用于合成生物学和天然产物应用的高产 链霉菌 转录翻译工具包

Published: September 10, 2021
doi:

Summary

该协议详细介绍了从 委内瑞拉链霉菌 无细胞转录翻译(TX-TL)系统合成高产量重组蛋白的增强方法。

Abstract

链霉菌 属是临床抗生素和工业化学品的主要来源。 委内瑞拉链霉菌 ATCC 10712是一种快速生长的菌株,是氯霉素,jadomycin和pikromycin的天然生产者,这使其成为下一代合成生物学底盘的有吸引力的候选者。因此,加速 委内瑞拉链球菌 ATCC 10712以及其他 链霉菌 属模型开发的遗传工具对于天然产物工程和发现是非常理想的。为此,该方案提供了专用 的委内瑞拉链球菌 ATCC 10712无细胞系统,以实现高G + C(%)基因的高产异源表达。该方案适用于96孔或384孔板形式的小规模(10-100μL)间歇反应,而反应可能可扩展。无细胞系统坚固耐用,可以在最小的设置中实现一系列重组蛋白的高产量(约5-10 μ M)。这项工作还结合了广泛的质粒工具集,用于实时测量mRNA和蛋白质合成,以及标记蛋白质的凝胶内荧光染色。该方案还可以与高通量基因表达表征工作流程或研究放线菌基因组中存在的高G + C(%)基因的酶途径相结合。

Introduction

无细胞转录-翻译 (TX-TL) 系统为合成生物学提供了一个理想的原型设计平台,以实现快速的设计-构建-测试-学习周期,这是合成生物学的概念工程框架1。此外,人们对在开放反应环境中用于高价值重组蛋白生产的 TX-TL 系统的兴趣日益浓厚例如,在抗体-药物偶联物中掺入非标准氨基酸3。具体而言,TX-TL需要细胞提取物,质粒或线性DNA以及能量溶液来催化批量或半连续反应中的蛋白质合成。虽然 大肠 杆菌 TX-TL 是主要的无细胞系统,但许多新兴的非型号 TX-TL 系统已引起不同应用的关注45678。TX-TL 的主要优势包括灵活的可扩展性(纳升至升级)910、强大的再现性和自动化工作流程81112。特别是,TX-TL的自动化允许加速遗传部分和调节元件的表征81213

在反应设置方面,TX-TL需要一次和二次能量源,以及氨基酸,辅因子,添加剂和模板DNA序列。核苷酸三磷酸盐(NTPs)为驱动初始mRNA(ATP,GTP,CTP和UTP)和蛋白质合成(仅ATP和GTP)提供了主要能量来源。为了提高TX-TL产量,NTP通过二次能源的分解代谢再生,例如麦芽糖14,麦芽糖糊精15,葡萄糖14,3-磷酸甘油酯(3-PGA)16,磷酸烯醇丙酮酸盐17和L-谷氨酸18。这种固有的代谢活动令人惊讶地具有多功能性,但研究很少,特别是在新兴的TX-TL系统中。每种能源在ATP产率、化学稳定性和成本方面都有不同的性质和优势,这是扩大TX-TL反应的重要考虑因素。到目前为止,目前 大肠杆菌 TX-TL的方案对于模型绿色荧光蛋白(GFP)已达到4.0mg / mL(~157μM),使用3-PGA(30mM),麦芽糖糊精(60mM)和D-核糖(30 mM)的混合物作为二次能量源19

最近,人们对研究TX-TL系统中的二次代谢物生物合成途径的兴趣日益浓厚202122。具体而言,放线菌是继发代谢物的主要来源,包括抗生素和农药2324。他们的基因组富含所谓的生物合成基因簇(BGC),其编码二次代谢物生物合成的酶途径。为了研究放线菌遗传部分和生物合成途径,最近开发了一系列基于链霉菌的TX-TL系统562526。这些专门的链霉菌TX-TL系统具有潜在的益处,原因如下:[1]为链霉菌spp.26的酶提供天然蛋白质折叠环境;[2] 获得高G+C(%)基因表达的最佳tRNA库;[3]活跃的初级代谢,可能被劫持以提供生物合成前体;和[4]提供天然细胞提取物中存在的二次代谢的酶,前体或辅因子。因此,最近建立了一个高收益的 S.venezuelae TX-TL 工具包来利用这些独特的功能5

委内瑞拉链霉菌 是合成生物学的新兴宿主,在工业生物技术领域具有丰富的历史5272829 ,并作为研究放线菌细胞分裂和遗传调控的模型系统303132。主要类型菌株 S. venezuelae ATCC 10712具有相对较大的基因组,为8.22 Mb,G + C含量为72.5%(加入号:CP029197),编码7377个编码序列,21个rRNA,67个tRNA和30个生物合成基因簇27。在合成生物学中, S. venezuelae ATCC 10712是生物合成途径异源表达的有吸引力的底盘。与大多数其他 链霉菌 染色剂不同,它提供了几个关键优势,包括快速的倍增时间(约40分钟),广泛的遗传和实验工具528,缺乏菌丝结块以及在液体培养基中孢子2833。一些研究还证明了 委内瑞拉链球菌 用于多种次级代谢物的异源生产,包括聚酮类,核糖体和非核糖体肽3435363738。这些组合特征使该菌株成为合成生物学和代谢工程应用的有吸引力的微生物宿主。虽然 委内瑞拉链球菌 不是异源基因表达的主要 链霉菌 模型,但随着进一步的发展,它已准备好在天然产物发现中得到更广泛的应用。

本手稿介绍了高产委内瑞拉链球菌 TX-TL 系统的详细实验方案(图 1),该系统已从先前发表的原始协议进行了更新26。在这项工作中,能量溶液和反应条件已经过优化,使用标准质粒pTU1-A-SP44-mScarlet-I,在4小时,10μL间歇反应中将mScarlet-I报告蛋白的蛋白质产量提高到260μg/mL。该质粒经过专门设计,可实现检测蛋白质表达的各种方法。该协议也得到了简化,而能源系统已经过优化,以降低建立无细胞反应的复杂性和成本,而不会影响产量。除了优化的TX-TL系统外,还开发了一个遗传部分库,用于微调基因表达,并作为实时监测TX-TL的荧光工具,从而为链霉菌属和相关放线菌的基因表达和天然产物生物合成途径原型化创建了一个多功能平台。

在这项工作中,推荐的标准质粒(pTU1-A-SP44-mScarlet-I)可用于在新实验室中建立委内瑞拉链球菌TX-TL工作流程,并且可以在AddGene上使用(参见补充表S1)。pTU1-A-SP44-mScarlet-I为用户提供了研究其他开放式阅读框架(ORF)的灵活性。mScarlet-I ORF是针对委内瑞拉链球菌基因表达而优化的密码子。SP44启动子是一种强的构成性启动子,在大肠杆菌链霉菌spp.39中均具有高活性。质粒具有两个独特的限制性内切酶位点(NdeI,BamHI),允许使用联合C端FLAG标签和荧光素砷发夹(FlAsH)粘合剂标签系统在框架内对新的ORF进行亚克隆。或者,在亚克隆新基因后,可以通过包含终止密码子来去除这两个标签。使用该碱基载体,已经证明了一系列蛋白质的高产表达,即来自土霉素生物合成途径的蛋白质和来自Streptomyces rimosus的未表征的非核糖体肽合成酶(NRPS)(图2)。在mRNA检测方面,pTU1-A-SP44-mScarlet-I标准质粒含有dBroccoli适配体(在3′-未翻译区域),用于使用3,5-二氟-4-羟基苄叉亚氮烷(DFHBI)探针进行检测。为了提高灵活性,AddGene上还提供了EcoFlex40兼容MoClo部件的工具集,包括EcoFlex兼容的链霉菌穿梭载体(pSF1C-A-RFP/ pSF2C-A-RFP)和一系列pTU1-A-SP44变体质粒,表达超级折叠绿色荧光蛋白(sfGFP),mScarlet-I,mVenus-I和β葡萄糖醛酸酶(GUS)。特别是,pSF1C-A质粒来自pAV-gapdh28,并固化为MoClo组装的BsaI / BsmBI位点。pSF1C-A-RFP/pSF2C-A-RFP 相当于 EcoFlex40 的 pTU1-A-RFP/pTU2-A-RFP,但包含链霉菌属中偶联和染色体整合的附加功能。使用phiC31整合酶系统28

该协议的第一阶段涉及 委内瑞拉链球菌 ATCC 10712或密切相关菌株的生长,中等指数阶段的细胞收获,细胞洗涤步骤以及S30A和S30B缓冲液中的平衡。该阶段需要三天,细胞生长的时间可用于制备剩余的组分,如下所述。然后通过超声处理裂解收获的细胞,澄清并进行径流反应。在制备的最后阶段,可以制备细胞提取物以在-80°C下长期储存,以最大限度地减少活性损失。对于使用此方案组装TX-TL反应,提出了 链霉菌 预混液(SMM),并可选择最小能量溶液格式(MES),可提供相当的产量。此外,建议将 委内瑞拉链球菌 ATCC 10712的新鲜培养物从-80°C的甘油储备到GYM琼脂平板上,并在28°C下孵育至少48-72小时,直到单个菌落可见。以下步骤应仅使用新鲜培养物。

Protocol

注:有关GYM培养基和琼脂平板以及S30A和S30B洗涤缓冲液的配方,请参见表1和表2。 1. 准备解决方案和一般指导 制备后将所有溶液,细胞(生长后)和细胞提取物保存在冰上,除非有例外。 在室温下储存1M Mg-谷氨酸盐,4M K-谷氨酸盐,40%(w / v)PEG 6000,1 g / mL聚乙烯磺酸的库存,以及在-80°C下储存所有其他库存。 尽量减少冻融循环的次?…

Representative Results

提供该详细实验方案作为示例,以帮助用户建立基于委内瑞拉链球菌ATCC 10712模型菌株的链霉菌TX-TL系统(图1)。用户可以寻求研究其他链霉菌菌株;然而,具有较长倍增时间或不同生长偏好的其他菌株的生长/收获阶段将需要定制优化才能达到峰值结果。对于代表性结果,对来自pTU1-A-SP44-mScarlet-I标准质粒的mScarlet-I荧光蛋白(图2</stron…

Discussion

在这份手稿中,描述了一种高收益的委内瑞拉链球菌TX-TL协议,并提供了详细的步骤,这些步骤对于有经验的用户和新用户来说都是直接的。现有链霉菌45大肠杆菌TX-TL41方案的几个特征已被移除,以建立委内瑞拉链球菌TX-TL526的最小但高产量的方案。这里推荐的工作流程是确保委内瑞…

Declarações

The authors have nothing to disclose.

Acknowledgements

作者希望感谢以下研究支持:EPSRC [EP/K038648/1] 为SJM提供PSF作为PDRA;惠康信托基金会在伦敦帝国理工学院为澳博与PSF赞助了ISSF奖学金;英国皇家学会研究资助[RGS\R1\191186];肯特大学SJM的惠康信托SEED奖[217528/Z/19/Z];和肯特大学KC的全球挑战研究基金(GCRF)博士奖学金。

Materials

2.5 L UltraYield Flask Thomson 931136-B
3-PGA (>93%) Sigma P8877
384 Well Black/Clear Bottom Plate ThermoFisher 10692202
Ammonium chloride (98%) Fluorochem 44722
ATP, CTP, UTP, GTP (100 mM solution, >99%) ThermoFisher R0481
Carbenicillin (contact supplier for purity) Melford C46000-25.0
D-(+)-glucose (contact supplier for purity) Melford G32040
DFHBI (≥98% – HPLC) Sigma SML1627
DTT (contact supplier for purity) Melford MB1015
FlAsH-EDT2 (contact supplier for purity) Santa Cruz Biotech sc-363644
Glucose-6-phosphate (>98%) Sigma G7879
HEPES Free Acid (contact supplier for purity) Melford B2001
L-glutamic acid hemimagnesium salt tetrahydrate (>98%) Sigma 49605
Magnesium chloride (98%) Fluorochem 494356
Malt extract Sigma 70167-500G
PEG-6000 Sigma 807491
Pierce 96-well Microdialysis Plate, 10K MWCO ThermoFisher 88260
Poly(vinyl sulfate) potassium salt Sigma 271969
Potassium glutamate (>99%) Sigma G1149
RTS amino acid sampler 5 Prime 2401530
Sodium chloride (99%) Fluorochem 94554
Supelclean LC-18 SPE C-18 SPE column (1 g) Sigma 505471
Yeast Extract Melford Y1333
Equipment
Platereader BMG Omega

Referências

  1. Carbonell, P., et al. An automated Design-Build-Test-Learn pipeline for enhanced microbial production of fine chemicals. Communications Biology. 1, 66 (2018).
  2. Gregorio, N. E., Levine, M. Z., Oza, J. P. A user’s guide to cell-free protein synthesis. Methods Protocols. 2 (1), 24 (2019).
  3. Zimmerman, E. S., et al. Production of site-specific antibody-drug conjugates using optimized non-natural amino acids in a cell-free expression system. Bioconjugate Chemistry. 25 (2), 351-361 (2014).
  4. Wiegand, D. J., Lee, H. H., Ostrov, N., Church, G. M. Cell-free protein expression using the rapidly growing bacterium Vibrio natriegens. Journal of Visualized Experiments: JoVE. (145), e59495 (2019).
  5. Moore, S. J., et al. A Streptomyces venezuelae cell-free toolkit for synthetic biology. ACS Synthetic Biology. 10 (2), 402-411 (2021).
  6. Xu, H., Liu, W. -. Q., Li, J. Translation related factors improve the productivity of a Streptomyces-based cell-free protein synthesis system. ACS Synthetic Biology. 9 (5), 1221-1224 (2020).
  7. Yim, S. S., et al. Multiplex transcriptional characterizations across diverse bacterial species using cell-free systems. Molecular Systems Biology. 15 (8), 8875 (2019).
  8. Moore, S. J., et al. Rapid acquisition and model-based analysis of cell-free transcription-translation reactions from nonmodel bacteria. Proceedings of the National Academy of Sciences of the United States of America. 115 (19), 4340-4349 (2018).
  9. Zawada, J. F., et al. Microscale to manufacturing scale-up of cell-free cytokine production–a new approach for shortening protein production development timelines. Biotechnology and Bioengineering. 108 (7), 1570-1578 (2011).
  10. Geertz, M., Shore, D., Maerkl, S. J. Massively parallel measurements of molecular interaction kinetics on a microfluidic platform. Proceedings of the National Academy of Sciences of the United States of America. 109 (41), 16540-16545 (2012).
  11. McManus, J. B., Emanuel, P. A., Murray, R. M., Lux, M. W. A method for cost-effective and rapid characterization of engineered T7-based transcription factors by cell-free protein synthesis reveals insights into the regulation of T7 RNA polymerase-driven expression. Archives of Biochemistry and Biophysics. 674, 108045 (2019).
  12. McManus, J. B., et al. A method for cost-effective and rapid characterization of genetic parts. bioRxiv. , (2021).
  13. Park, J., Yim, S. S., Wang, H. H. High-throughput transcriptional characterization of regulatory sequences from bacterial Biosynthetic Gene Clusters. ACS Synthetic Biology. , (2021).
  14. Caschera, F., Noireaux, V. Synthesis of 2.3 mg/ml of protein with an all Escherichia coli cell-free transcription-translation system. Biochimie. 99, 162-168 (2014).
  15. Caschera, F., Noireaux, V. A cost-effective polyphosphate-based metabolism fuels an all E. coli cell-free expression system. Metabolic Engineering. 27, 29-37 (2015).
  16. Shin, J., Noireaux, V. Efficient cell-free expression with the endogenous E. coli RNA polymerase and sigma factor 70. Journal of Biological Engineering. 4, 8 (2010).
  17. Karim, A. S., Heggestad, J. T., Crowe, S. A., Jewett, M. C. Controlling cell-free metabolism through physiochemical perturbations. Metabolic Engineering. 45, 86-94 (2018).
  18. Cai, Q., et al. A simplified and robust protocol for immunoglobulin expression in Escherichia coli cell-free protein synthesis systems. Biotechnology Progress. 31 (3), 823-831 (2015).
  19. Garenne, D., Thompson, S., Brisson, A., Khakimzhan, A., Noireaux, V. The all-E. coli TXTL toolbox 3.0: New capabilities of a cell-free synthetic biology platform. Synthetic Biology. , (2021).
  20. Goering, A. W., et al. In vitro reconstruction of nonribosomal peptide biosynthesis directly from DNA using cell-free protein synthesis. ACS Synthetic Biology. 6 (1), 39-44 (2017).
  21. Khatri, Y., et al. Multicomponent microscale biosynthesis of unnatural cyanobacterial indole alkaloids. ACS Synthetic Biology. 9 (6), 1349-1360 (2020).
  22. Zhuang, L., et al. Total in vitro biosynthesis of the nonribosomal macrolactone peptide valinomycin. Metabolic Engineering. 60, 37-44 (2020).
  23. Hoskisson, P. A., Seipke, R. F. Cryptic or silent? The known unknowns, unknown knowns, and unknown unknowns of secondary metabolism. mBio. 11 (5), 02642 (2020).
  24. Bentley, S. D., et al. Complete genome sequence of the model actinomycete Streptomyces coelicolor A3(2). Nature. 417 (6885), 141-147 (2002).
  25. Li, J., Wang, H., Kwon, Y. -. C., Jewett, M. C. Establishing a high yielding Streptomyces-based cell-free protein synthesis system. Biotechnology and Bioengineering. 114 (6), 1343-1353 (2017).
  26. Moore, S. J., Lai, H. -. E., Needham, H., Polizzi, K. M., Freemont, P. S. Streptomyces venezuelae TX-TL – a next generation cell-free synthetic biology tool. Biotechnology Journal. 12 (4), (2017).
  27. Kim, W., et al. Comparative genomics determines strain-dependent secondary metabolite production in Streptomyces venezuelae strains. Biomolecules. 10 (6), 864 (2020).
  28. Phelan, R. M., et al. Development of next generation synthetic biology tools for use in Streptomyces venezuelae. ACS Synthetic Biology. 6 (1), 159-166 (2017).
  29. Song, J. Y., et al. Complete genome sequence of Streptomyces venezuelae ATCC 15439, a promising cell factory for production of secondary metabolites. Journal of Biotechnology. 219, 57-58 (2016).
  30. Bush, M. J., Bibb, M. J., Chandra, G., Findlay, K. C., Buttner, M. J. Genes required for aerial growth, cell division, and chromosome segregation are targets of WhiA before sporulation in Streptomyces venezuelae. mBio. 4 (5), 00684 (2013).
  31. Schumacher, M. A., et al. The crystal structure of the RsbN-σBldN complex from Streptomyces venezuelae defines a new structural class of anti-σ factor. Nucleic Acids Research. 46 (14), 7405-7417 (2018).
  32. Ramos-León, F., et al. A conserved cell division protein directly regulates FtsZ dynamics in filamentous and unicellular actinobacteria. Elife. 10, 63387 (2021).
  33. Bush, M. J., Tschowri, N., Schlimpert, S., Flärdh, K., Buttner, M. J. c-di-GMP signalling and the regulation of developmental transitions in Streptomycetes. Nature Reviews. Microbiology. 13 (12), 749-760 (2015).
  34. Ehrlich, J., Gottlieb, D., Burkholder, P. R., Anderson, L. E., Pridham, T. G. Streptomyces venezuelae, n. sp., the source of chloromycetin. Journal of Bacteriology. 56 (4), 467-477 (1948).
  35. Inahashi, Y., et al. Watasemycin biosynthesis in Streptomyces venezuelae: thiazoline C-methylation by a type B radical-SAM methylase homologue. Chemical Science. 8 (4), 2823-2831 (2017).
  36. Jakeman, D. L., et al. Antimicrobial activities of jadomycin B and structurally related analogues. Antimicrobial Agents and Chemotherapy. 53 (3), 1245-1247 (2009).
  37. Kodani, S., Sato, K., Hemmi, H., Ohnish-Kameyama, M. Isolation and structural determination of a new hydrophobic peptide venepeptide from Streptomyces venezuelae. Journal of Antibiotics. 67 (12), 839-842 (2014).
  38. Akey, D. L., et al. Structural basis for macrolactonization by the pikromycin thioesterase. Nature Chemical Biology. 2 (10), 537-542 (2006).
  39. Bai, C., et al. Exploiting a precise design of universal synthetic modular regulatory elements to unlock the microbial natural products in Streptomyces. Proceedings of the National Academy of Sciences of the United States of America. 112 (39), 12181-12186 (2015).
  40. Moore, S. J., et al. EcoFlex: A multifunctional MoClo kit for E. coli synthetic biology. ACS Synthetic Biology. 5 (10), 1059-1069 (2016).
  41. Sun, Z. Z., et al. Protocols for implementing an Escherichia coli based TX-TL cell-free expression system for synthetic biology. Journal of Visualized Experiments: JoVE. (79), e50762 (2013).
  42. Kim, D. M., Choi, C. Y. A semicontinuous prokaryotic coupled transcription/translation system using a dialysis membrane. Biotechnology Progress. 12 (5), 645-649 (1996).
  43. Liu, Y., Fritz, B. R., Anderson, M. J., Schoborg, J. A., Jewett, M. C. Characterizing and alleviating substrate limitations for improved in vitro ribosome construction. ACS Synthetic Biology. 4 (4), 454-462 (2015).
  44. Bindels, D. S., et al. mScarlet: a bright monomeric red fluorescent protein for cellular imaging. Nature Methods. 14, 53-56 (2017).
  45. Hopword, D. A., Kieser, T., Bibb, M. J., Buttner, M. J., Chater, K. Practical Streptomyces genetics. John Innes Foundation. , (2000).
  46. Hunter, D. J. B., Bhumkar, A., Giles, N., Sierecki, E., Gambin, Y. Unexpected instabilities explain batch-to-batch variability in cell-free protein expression systems. Biotechnology and Bioengineering. 115 (8), 1904-1914 (2018).
  47. Dopp, J. L., Jo, Y. R., Reuel, N. F. Methods to reduce variability in E. coli-based cell-free protein expression experiments. Synthetic and Systems Biotechnology. 4 (4), 204-211 (2019).
  48. Hoff, G., Bertrand, C., Piotrowski, E., Thibessard, A., Leblond, P. Genome plasticity is governed by double strand break DNA repair in Streptomyces. Scientific Reports. 8, 5272 (2018).
  49. Bibb, M. J. Regulation of secondary metabolism in streptomycetes. Current Opinion in Microbiology. 8 (2), 208-215 (2005).
  50. Weber, T., et al. antiSMASH 3.0-a comprehensive resource for the genome mining of biosynthetic gene clusters. Nucleic Acids Research. 43 (1), 237-243 (2015).
  51. Navarro-Muñoz, J. C., et al. A computational framework to explore large-scale biosynthetic diversity. Nature Chemical Biology. 16, 60-68 (2020).
  52. Alanjary, M., et al. The Antibiotic Resistant Target Seeker (ARTS), an exploration engine for antibiotic cluster prioritization and novel drug target discovery. Nucleic Acids Research. 45 (1), 42-48 (2017).
  53. Medema, M. H., Fischbach, M. A. Computational approaches to natural product discovery. Nature Chemical Biology. 11 (9), 639-648 (2015).
  54. Whitford, C. M., Cruz-Morales, P., Keasling, J. D., Weber, T. The Design-Build-Test-Learn cycle for metabolic engineering of Streptomycetes. Essays in Biochemistry. , (2021).
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Toh, M., Chengan, K., Hanson, T., Freemont, P. S., Moore, S. J. A High-Yield Streptomyces Transcription-Translation Toolkit for Synthetic Biology and Natural Product Applications. J. Vis. Exp. (175), e63012, doi:10.3791/63012 (2021).

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