该协议描述了用于自下而上制备RNA和产生合成细胞的蛋白质的方法、材料、设备和步骤。合成细胞的内水腔含有S30细菌裂解,封装在脂质双层层(即稳定脂质体)内,使用油水乳液转移方法。
合成细胞构造的自下而上装配方法是隔离和研究细胞模拟环境中细胞过程的有效工具。此外,无细胞表达系统的发展已经证明了以受控方式重组蛋白质生产、转录和翻译过程(DNA+RNA+蛋白质)的能力,利用合成生物学。在这里,我们描述了一种制备无细胞表达系统的协议,包括生产一种有效的细菌水合物,并将这种水泡封装在富含胆固醇的脂质型巨型单层囊泡(GUVs)(即稳定脂质体)内,以形成合成细胞。该协议描述了合成细胞成分的准备方法,包括活性细菌裂解物的产生,然后根据油水乳液转移方法对合成细胞进行详细的逐步制备。这些有助于以简单和负担得起的方式生产数百万个合成细胞,具有用于生产不同类型的蛋白质的高多功能性。所得合成细胞可用于研究分离环境中的蛋白质/RNA的产生和活性,在定向进化中,以及作为在体内按需生产治疗蛋白的受控药物输送平台。
合成细胞是类似细胞的人造粒子,模仿活细胞的一个或多个功能,如分裂、形成膜相互作用和根据遗传代码11、2、32,3合成蛋白质的能力。包含无细胞蛋白合成(CFPS)系统的合成细胞具有很高的模块化,因为它们能够在DNA模板发生改变后产生各种蛋白质和RNA序列。CFPS系统以细胞裂解、纯化成分或合成成分为基础,提供一种有吸引力的替代蛋白,包括蛋白质合成所需的所有转录和翻译机制,如核糖体、RNA聚合酶、氨基酸和能量源(例如,三磷甘油酸盐和三磷酸腺)4、5、6、7、8、9。4,5,6,7,8,9将CFPS系统封装在脂质囊泡内,无需依赖活细胞10即可简单高效地生产蛋白质。此外,该平台允许合成可能在自然细胞内降解的肽,产生对活细胞有毒的蛋白质,以及用非天然氨基酸11,12,12修饰蛋白质。合成细胞已被作为研究目的的模型,研究从进化角度1,13,13实现细胞寿命所需的最小细胞成分。合成细胞也被用来建立和实施遗传回路,并作为定向进化的模型14,15,16。15,1614其他研究的重点是合成细胞模仿自然细胞生物活动的能力,旨在取代受损的自然细胞,如糖尿病患者的β细胞。此外,这些CFPS封装合成细胞产生各种治疗性蛋白质的能力说明了其潜力,被纳入临床使用18。
在这里,我们描述了一个自下而上的实验室规模协议(图1),用于生产基于CFPS系统封装在脂质囊泡中的RNA和产生蛋白质的合成细胞。这表明,合成细胞平台作为新型药物输送系统,用于在体内生产治疗性蛋白质药物的可能性。以前的研究已经研究了CFPS反应和细胞水合制剂过程44,8,208,20的优化。此外,还应用了几种细胞大小的脂质体制备技术,如微流体和聚合物基液滴稳定方法21、22、23,,22,在脂质体脂质组成24、25、2625,26中也有所不同24。23在所介绍的协议中,合成细胞采用水浸液转移法产生,封装过程在低温(<4°C)5、10、24、27、285,10,24,27,28下进行。这些温和的条件被发现有利于保持分子机械的生物功能完整性,即核糖体和蛋白质27,29,30。27,29,30颗粒的脂质组成由胆固醇和1-棕榈-2-奥莱基-sn-糖-3-磷脂素(POPC)组成。第一种存在于所有哺乳动物细胞膜中,对膜的稳定性、刚度和渗透性降低至关重要,后者模仿哺乳动物磷脂成分11、13。11,细胞转录和转化分子机械从BL21(DE3)大肠杆菌(大肠杆菌)菌株中提取,该菌株由pAR1219质粒过度表达T7RNA聚合酶转化,以增加CFPS效力和蛋白质合成。该系统已用于产生诊断和治疗蛋白,31体外和体内19的分子量高达66kDa。以下协议为合成细胞系统的生产提供了一种简单而有效的方法,可以解决与自然界中蛋白质合成相关的广泛基本问题,也可用于药物输送应用。
该协议引入了一种简单且经济的方法,用于生产大量产生蛋白质的合成细胞。活性细胞的产生取决于谨慎和准确地执行协议,并侧重于几个关键步骤。在该方法的精致部分,在细胞水致之前达到适当的细菌密度,在细菌水致酶中达到足够数量的蛋白质至关重要。其次,在4°C下进行流化过程,用液氮快速冷冻液化酶,以保持蛋白质活性。此外,在该协议中,我们使用大肠杆菌BL21(DE3)细胞?…
The authors have nothing to disclose.
这项工作得到了ERC-STG-2015-680242的支持。
作者还承认技术综合癌症中心(TICC)的支持;罗素浆果纳米技术研究所;罗瑞一·洛基生命科学与工程跨学科中心;以色列经济部为卡明赠款(52752);以色列科学技术和空间部首席科学家办公室(3-11878);以色列科学基金会(1778/13,1421/17);以色列癌症协会(2015-0116);德国-以色列科学研究与发展基金会为GIF青年赠款(I-2328-1139.10/2012);欧洲联盟FP-7职业一体化赠款IRG方案(908049);磷脂研究中心赠款;罗森布拉特癌症研究基金会,马拉特家庭基金会赠款;和昂格家庭基金会施罗德承认阿隆和陶布奖学金。O. Adir承认谢尔曼和古特维尔斯奖学金。陈承认谢尔曼奖学金。克林斯基感谢罗斯柴尔德·凯撒利亚基金会的阿丽亚娜·德罗斯柴尔德夫人博士计划。
A. Reagents required for step 1 (S30-T7 lysate preparation) | |||
E.coli BL21 (DE3) | NEB | C2527 | E.coli BL21 (DE3). |
pAR1219 | Sigma | T2076 | TargeTron vector for transformation. |
Stock solution of 50 mg/mL Ampicillin | Sigma | A9518 | Stored at -20 °C. |
10 g/L Bacto-tryptone | BD Bioscience | 211705 | For preparation of Luria Bertani (LB) agar (1.5%) plate. |
10 g/L Sodium chloride (NaCl) | Bio-Lab | 19030591 | |
5 g/L Bacto-Yeast extract | BD Bioscience | 212750 | |
15 g/L Agar agar purified | Merck | 1.01614.5007 | |
50 µg/mL Ampicillin | Sigma | A9518 | |
10 g/L Bacto-tryptone | BD Bioscience | 211705 | For preparation of Luria Bertani (LB) media (20 mL). |
10 g/L Sodium chloride (NaCl) | Bio-Lab | 19030591 | |
5 g/L Bacto-Yeast extract | BD Bioscience | 212750 | |
50 µg/mL Ampicillin | Sigma | A9518 | |
12 g/L Bacto-tryptone | BD Bioscience | 211705 | For preparation of Terrific Broth (TB) media (1 L). |
24 g/L Bacto-Yeast extract | BD Bioscience | 212750 | |
4% (v/v) Glycerol anhydrous | Bio-Lab | 7120501 | |
2.32 g/L K2HPO4 | Spectrum chemical | P1383 | |
12.54 g/L KH2PO4 | Spectrum chemical | P1380 | |
50 µg/mL Ampicillin | Sigma | A9518 | |
Stock solution of 100 mM Isopropyl β-D-1-thiogalactopyranoside (IPTG) | INALCO | INA-1758-1400 | Filtered using 0.2 µm hydrophilic PVDF syringe filter. |
Stock solution of 0.1 M dithiothreitol (DTT) | TCI | D1071 | Filtered using 0.2 µm hydrophilic PVDF syringe filter. |
10 mM Tris-acetate at pH = 7.4 | Sigma | T1503 | S30 lysate buffer (1.5 L) |
14 mM magnesium acetate | Merck | 1.05819.0250 | |
60 mM potassium acetate | Carlo Erba | 470147 | |
1 mM DTT | TCI | D1071 | |
0.5 mL/L 2-mercaptoethanol | Sigma | M6250 | |
Equipment required for step 1 | |||
100 mL sterilized Erlenmeyer flasks | Thermo Scientific | 50-154-2846 | 2 flasks |
2 L sterilized Erlenmeyer flasks with baffles | KIMAX-KIMBLE | 25630 | 2 flasks |
Floor incubator shaker | MRC | TOU-120-2 | Laboratory shaker incubator 450x450mm, 400rpm, 70 °C |
Centrifuge | Thermo Scientific | 75004270 | (75003340) – Fiberlite F10-6 x 100 LEX Fixed-Angle Rotor. Should enable at least 13,000 x g. * Pre-cooled to 4 °C. |
High pressure homogenizer | AVESTIN | EmulsiFlex-C3 | Pre-cooled to 4 °C. |
-80oC freezer | SO-LOW | U85-18 | |
Sterilized 1.5 mL plastic tubes | Eppendorf | 30120086 | Preferably pre-cooled to -20 °C. |
Spectrophotometer | TECAN | IN-MNANO | Infinite M200 pro |
96-well transparent plate | Thermo Scientific | 167008 | |
Sterilized graduated cylinder | Corning | ||
Sterilized centrifuge tubes | Eppendorf | 30120086 | Preferably pre-cooled to -20 °C. |
Sterilized pipette tips | Corning | Preferably pre-cooled to -20 °C. | |
Crushed ice bucket | Bel-Art | M18848-4001 | |
Small liquid nitrogen tank | NALGENE | 4150-4000 | |
B. Reagents required for step 3 (lipids in oil solution preparation): | |||
1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) | Lipoid | 556400 | Powder |
Cholesterol | Sigma | C8667 | Powder |
Chloroform | Bio-Lab | 3082301 | |
Mineral oil | Sigma | M5904 | Light oil |
Equipment required for step 2 | |||
Vortex mixer | Scientific industries | SI-0256 | |
Heating block | TECHNE | FDB03AD | Pre-heated to 80 °C. Should enable controlled temperature. |
2 mL screw neck glass vials | CSI Analytical Innovations | VT009M-1232 | For a larger scale, use 50 mL falcons and evaporate the chloroform using rotary evaporator. |
9mm Screw Cap | CSI Analytical Innovations | C395R-09LC | |
C. Reagents required for step 3 (inner and feeding reaction mixtures): | |||
HEPES | Spectrum | H1089 | 1 M HEPES-KOH (pH = 8) – pH buffer |
Potassium hydroxide (KOH) | Frutarom | 55290 | |
1 M Magnesium acetate | Merck | 1.05819.0250 | Co-factor and negative charge stabilizor. |
1 M Potassium acetate | Carlo Erba | 470147 | Negative charge stabilizor. |
5.2 M Ammonium acetate | Merck | 1.01116.1000 | Stabilizes negative charge. |
50% (w/v) Polyethylene glycol 6000 (PEG) | Merck | 8.07491.1000 | Increases the concentration of the macromolecules. |
0.5 M 3-phosphoglycerate (3-PGA) | Sigma | P8877 | Secondary energy source. |
50 mM Amino acids mixture I | Sigma | LAA21-1KT | Amino acids additive. Contains: 50 mM of each of the following 17 natural amino acids – alanine, arginine, asparagine, aspartic acid, cysteine, glutamine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, proline, serine, threonine, and valine. |
50 mM Amino acids mixture II | Sigma | LAA21-1KT | Amino acids additive. Contains: 50 mM of each of the following 3 natural amino acids – tryptophan, phenylalanine, and tyrosine. |
100 mM Adenine triphosphate (ATP) | Sigma | A3377 | Nucleotides & energy source. |
50 mM Guanidine triphosphate (GTP) | Sigma | G8877 | Nucleotides & energy source. |
100 mM Uridine triphosphate (UTP) | ACROS ORGANICS | 226310010 | Nucleotides additive. |
100 mM Isopropyl β-D-1-thiogalactopyranoside (IPTG) | INALCO | INA-1758-1400 | Genes expression induction. |
2 M Sucrose | J.T. Baker | 1933078 | Generating a density gradient. |
2 M Glucose | Sigma | 16301 | Generating a density gradient. |
H2O UltraPure Water (UPW) | Bio-Lab | 2321777500 | DNase & RNase free |
S30-T7 lysate | _ | _ | Prepared at step 1. Source of transcription & translation components. Store at -80 °c, thaw on crashed ice just before usage. |
Stock of DNA plasmid of choice | _ | _ | Contains the sequence for the requested protein. Under T7 promotor |
D. Equipment required for step 4 (synthetic cells preparation) | |||
Floor incubator shaker or Thermomixer | MRC | TOU-120-2 | Laboratory shaker incubator 450x450mm, 400rpm, 70 °C |
PHMT Grant Bio | PSC18 | Thermomixer | |
Centrifuge | Thermo Scientific | 75004270 | (75003629) – TX-400 4 x 400mL Swinging Bucket Rotor. Suited for 15 mL sized tubes. Preferably swinging buckets. Should enable at least 1000 x g. Pre-cooled to 4 °C. |
Table centrifuge | Thermo Scientific | 75002420 | (75003424) – 24 x 1.5/2.0mL rotor with ClickSeal. Suited for Eppendorf vials. Pre-cooled to 4 °C. |
Vortex mixer | Scientific industries | SI-0256 | |
Crushed ice bucket | Bel-Art | M18848-4001 | |
2 mL screw neck glass vials | CSI Analytical Innovations | VT009M-1232 | |
Sterile 15 mL plastic tubes | Thermo Scientific | 339651 | |
Sterilized 1.5 mL plastic tubes | Eppendorf | 30120086 | |
Sterilized pipette tips | Corning | Sterilized by autoclave. |