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Abstract Protein therapeutics are powerful tools in the fight against diabetes, cancers, growth disorders, and many other debilitating diseases. However, availability is limited due to cost and complications of production from living organisms. To make life‐saving protein therapeutics more available to the world, the possibility of magistral or point‐of‐care protein therapeutic production has gained focus. The recent invention and optimization of lyophilized “cell‐free” protein synthesis reagents and its demonstrated ability to produce highly active versions of FDA‐approved cancer therapeutics have increased its potential for low‐cost, single‐batch, magistral medicine. Here we present for the first time the concept of increased oxygen mass transfer in small‐batch, cell‐free protein synthesis (CFPS) reactions through air‐water foams. These “hydrofoam” reactions increased CFPS yields by up to 100%. Contrary to traditional protein synthesis using living organisms, where foam bubbles cause cell‐lysis and production losses, hydrofoam CFPS reactions are “cell‐free” and better tolerate foaming. Simulation and experimental results suggest that oxygen transfer is limiting in even small volume batch CFPS reactors and that the hydrofoam format improved oxygen transfer. This is further supported by CFPS reactions achieving higher yields when oxygen gas replaces air in the headspace of batch reactions. Improving CFPS yields with hydrofoam reduces the overall cost of biotherapeutic production, increasing availability to the developing world. Beyond protein therapeutic production, hydrofoam CFPS could also be used to enhance other CFPS applications including biosensing, biomanufacturing, and biocatalysis.
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Membrane protein synthesis: no cells required
Despite advances in membrane protein (MP) structural biology and a growing interest in their applications, these proteins remain challenging to study. Progress has been hindered by the complex nature of MPs and innovative methods will be required to circumvent technical hurdles. Cell-free protein synthesis (CFPS) is a burgeoning technique for synthesizing MPs directly into a membrane environment using reconstituted components of the cellular transcription and translation machinery in vitro. We provide an overview of CFPS and how this technique can be applied to the synthesis and study of MPs. We highlight numerous strategies including synthesis methods and folding environments, each with advantages and limitations, to provide a survey of how CFPS techniques can advance the study of MPs.
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- Award ID(s):
- 1935370
- PAR ID:
- 10502970
- Publisher / Repository:
- ScienceDirect
- Date Published:
- Journal Name:
- Trends in Biochemical Sciences
- Volume:
- 48
- Issue:
- 7
- ISSN:
- 0968-0004
- Page Range / eLocation ID:
- 642 to 654
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Cell-free protein synthesis (CFPS) is a platform technology that provides new opportunities for protein expression, metabolic engineering, therapeutic development, education, and more. The advantages of CFPS over in vivo protein expression include its open system, the elimination of reliance on living cells, and the ability to focus all system energy on production of the protein of interest. Over the last 60 years, the CFPS platform has grown and diversified greatly, and it continues to evolve today. Both new applications and new types of extracts based on a variety of organisms are current areas of development. However, new users interested in CFPS may find it challenging to implement a cell-free platform in their laboratory due to the technical and functional considerations involved in choosing and executing a platform that best suits their needs. Here we hope to reduce this barrier to implementing CFPS by clarifying the similarities and differences amongst cell-free platforms, highlighting the various applications that have been accomplished in each of them, and detailing the main methodological and instrumental requirement for their preparation. Additionally, this review will help to contextualize the landscape of work that has been done using CFPS and showcase the diversity of applications that it enables.more » « less
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Alarcon, Emilio I. (Ed.)Membrane proteins (MPs) are essential to many organisms’ major functions. They are notorious for being difficult to isolate and study, and mimicking native conditions for studies in vitro has proved to be a challenge. Lipid nanodiscs are among the most promising platforms for MP reconstitution, but they contain a relatively labile lipid bilayer and their use requires previous protein solubilization in detergent. These limitations have led to the testing of copolymers in new types of nanodisc platforms. Polymer-encased nanodiscs and polymer nanodiscs support functional MPs and address some of the limitations present in other MP reconstitution platforms. In this review, we provide a summary of recent developments in the use of polymers in nanodiscs.more » « less
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null (Ed.)Abstract Cell-free gene expression (CFE) systems from crude cellular extracts have attracted much attention for biomanufacturing and synthetic biology. However, activating membrane-dependent functionality of cell-derived vesicles in bacterial CFE systems has been limited. Here, we address this limitation by characterizing native membrane vesicles in Escherichia coli- based CFE extracts and describing methods to enrich vesicles with heterologous, membrane-bound machinery. As a model, we focus on bacterial glycoengineering. We first use multiple, orthogonal techniques to characterize vesicles and show how extract processing methods can be used to increase concentrations of membrane vesicles in CFE systems. Then, we show that extracts enriched in vesicle number also display enhanced concentrations of heterologous membrane protein cargo. Finally, we apply our methods to enrich membrane-bound oligosaccharyltransferases and lipid-linked oligosaccharides for improving cell-free N- linked and O -linked glycoprotein synthesis. We anticipate that these methods will facilitate on-demand glycoprotein production and enable new CFE systems with membrane-associated activities.more » « less
- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.tibs.2023.03.006
