Proteomics-Based Tools for Evaluation of Cell-Free Protein Synthesis

Area of Science:

• Biochemistry
• Proteomics
• Synthetic Biology

Background:

• Cell-free protein synthesis (CFPS) offers a powerful alternative to in vivo expression for producing proteins.
• Characterization of cell-free extracts and products is crucial for optimizing CFPS but remains a challenge.
• Mass spectrometry (MS)-based proteomics has emerged as a key technology for deep biological analysis.

Purpose of the Study:

• To evaluate the utility of MS-based proteomics for characterizing bacterial extracts used in CFPS.
• To analyze the protein products generated by CFPS reactions.
• To identify post-translational modifications (PTMs) in CFPS products and assess their functional implications.

Main Methods:

• Full proteome analysis of bacterial extracts used for transcription and translation.
• MS/MS analysis to identify and quantify proteins in CFPS reactions.
• Targeted analysis for specific PTMs, including phosphopantetheinylation.

Main Results:

• Identification of over 1000 proteins in cell-free extracts, revealing metabolic capabilities.
• Characterization of CFPS products, including the standard green fluorescent protein (GFP) and the large polyketide synthase DEBS1.
• Detection of premature termination in large protein synthesis and identification of PTMs, such as GFP chromophore formation and DEBS1 phosphopantetheinylation sites.

Conclusions:

• MS-based proteomics provides comprehensive characterization of CFPS extracts and products.
• The methodology enables assessment of protein synthesis fidelity and PTMs essential for function.
• This approach is valuable for advancing the optimization and application of CFPS technologies.