Preparing Protein Producing Synthetic Cells using Cell Free Bacterial Extracts, Liposomes and Emulsion Transfer
April 27th, 2020
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This protocol describes the method, materials, equipment and steps for bottom-up preparation of RNA and protein producing synthetic cells. The inner aqueous compartment of the synthetic cells contained the S30 bacterial lysate encapsulated within a lipid bilayer (i.e., stable liposomes), using a water-in-oil emulsion transfer method.
Overview
This protocol outlines the preparation of RNA and protein producing synthetic cells using a water-in-oil emulsion transfer method. The synthetic cells encapsulate S30 bacterial lysate within a lipid bilayer, providing a platform for therapeutic applications.
Key Study Components
Area of Science
- Biotechnology
- Synthetic Biology
- Cell-Free Systems
Background
- Synthetic cells can mimic biological functions.
- They are useful for studying the origins of life.
- These cells can be used for onsite therapeutic protein production.
- Applications include treatment for various diseases.
Purpose of Study
- To develop a method for producing synthetic cells.
- To facilitate RNA and protein expression.
- To explore therapeutic applications in drug delivery.
Methods Used
- Preparation of cell-free S30-T7 lysate.
- Encapsulation of lysate in lipid bilayers.
- Use of water-in-oil emulsion transfer method.
- Multi-step protocol with defined stopping points.
Main Results
- Successful encapsulation of S30 lysate in synthetic cells.
- Demonstrated potential for onsite protein production.
- Versatile platform for various therapeutic applications.
- Protocol can be performed over several days for efficiency.
Conclusions
- Synthetic cells represent a promising tool for research and therapy.
- Method is simple and cost-effective.
- Potential applications in treating metabolic diseases and cancer.
Frequently Asked Questions
What are synthetic cells?
Synthetic cells are engineered systems that mimic biological cells, capable of performing specific functions such as protein production.
How are RNA and proteins produced in synthetic cells?
RNA and proteins are produced using a cell-free system that encapsulates bacterial lysate within lipid bilayers.
What are the applications of synthetic cells?
They can be used for therapeutic protein production, drug delivery, and studying the origins of life.
Is the protocol complex to follow?
The protocol is designed to be simple and can be divided over several days for ease of execution.
What diseases can synthetic cells potentially treat?
They may be used for metabolic diseases, protein replacements, cancer, and possibly diabetes.
Executive Industry Relevance
This protocol enables the bottom-up assembly of synthetic cells for controlled protein production, offering a versatile platform for target validation and mechanistic de-risking in early discovery. By encapsulating cell-free expression systems within lipid vesicles, it supports reproducible quantitative outputs for assay development and phenotypic screening. The approach facilitates translational continuity from discovery through preclinical stages, particularly for therapeutic protein production and drug delivery applications.
Strategic Applications in Biopharma R&D
Early Discovery & Target Validation
- Scientific Value: Enables interrogation of transcriptional and translational mechanisms in an isolated, cell-mimicking environment.
- Operational Value: Provides a defined system for functional target validation through measurable protein output.
- Predictive Value: Supports lead identification by allowing rapid testing of genetic constructs for protein expression efficiency.
Screening & Assay Development
- Scientific Value: Generates quantitative fluorescence and luminescence readouts for high-content screening of genetic variants.
- Operational Value: Enables standardization of protein production assays via encapsulated lysate and controlled inner solution composition.
- Scalability: Facilitates production of millions of synthetic cells for reproducible compound or construct evaluation.
Translational & Preclinical Research
- Translational Relevance: Serves as a controlled platform for on-demand production of therapeutic proteins, supporting preclinical proof-of-concept.
- Mechanistic De-risking: Allows investigation of protein/RNA activity in isolation, reducing ambiguity in pathway interpretation.
- Predictive Confidence: Enables assessment of expression yield and stability prior to cellular system integration.
Pipeline & Workflow Integration
The method integrates into early discovery workflows by providing a cell-free expression system that bridges genetic design and functional validation, preceding cellular-based assays and preclinical models.
- Discovery Biology: Supports hypothesis testing of gene constructs through direct measurement of protein synthesis in a minimal system.
- Screening: Delivers assay-ready synthetic cells with quantitative outputs (fluorescence, luminescence) for evaluating expression performance.
- Analytics: Enables normalization of protein production data via sfGFP intensity thresholds and active cell population calculations.
- Translational Research: Connects to preclinical work by demonstrating potential for therapeutic protein production in a delivery-capable format.
- Enterprise Reuse: Establishes a reusable platform for protein production across multiple targets through lysate and plasmid interchangeability.
Operational & Enterprise Impact
- Scientific Value: Increases predictive confidence in target validation by reducing cellular complexity and isolating transcription-translation processes.
- Operational Value: Enhances reproducibility through standardized lysate preparation, lipid encapsulation, and emulsion transfer steps.
- Strategic Value: Improves capital efficiency by enabling rapid, low-cost iteration of expression constructs before cellular system investment.
- Portfolio Impact: Supports risk-adjusted prioritization by providing early, quantitative data on protein yield and functionality.
Implementation Considerations
- Requires expertise in bacterial culture, cell-free lysate preparation, and lipid handling.
- Depends on instrumentation including spectrophotometer, centrifuge, homogenizer, and fluorescence/luminescence detectors.
- Necessitates cross-team standardization of lysate activity, lipid composition, and inner solution formulation.
- Involves adaptation considerations for different plasmid constructs and target proteins via lysate origin and concentration tuning.
- Includes practical limitations such as the need for cold handling, fume extraction for chloroform, and defined stopping points for multi-day execution.
Biopharma FAQs
Why is lysate activity critical for synthetic cell function?
Lysate activity directly determines the capacity for transcription and translation within synthetic cells, as measured by sfGFP and Renilla luciferase output. Preserving activity through rapid processing and cold storage ensures reliable protein production. This is essential for generating consistent, quantitative readouts in screening applications.
How does the water-in-oil emulsion transfer method enable synthetic cell formation?
The method encapsulates the S30-T7 lysate and DNA plasmid inside lipid vesicles by forming and stabilizing an emulsion that undergoes sequential centrifugation steps. This process isolates a pellet of synthetic cells from the oil phase, which is then resuspended in feeding solution for protein expression. It allows scalable production of uniform synthetic cells in a simple, affordable manner.
What quantitative measurements validate protein production in synthetic cells?
Protein production is validated using Western blot analysis for sfGFP His6 detection, fluorescence microscopy for visual confirmation, and flow cytometry to quantify active synthetic cell populations based on sfGFP intensity. Luminescence measurements assess Renilla luciferase activity. These outputs enable normalization and comparison across conditions.
Why are replication requirements important for synthetic cell applications?
Replication ensures that observed protein production is not due to variability in lysate preparation or encapsulation efficiency, supporting reliable data for target validation. Consistent results across replicates build confidence in the system’s reproducibility for assay development. This is critical for cross-functional collaboration and decision-making in discovery pipelines.
What statistical analysis is needed before implementing this method in a discovery workflow?
Implementation requires analysis of fluorescence intensity thresholds to define active synthetic cell populations, as established by negative DNA controls. Mean fluorescence intensity must be normalized and diameter distributions calculated based on sfGFP signal. These statistical outputs enable objective comparison of protein production efficacy across genetic or condition variants.
