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12:48
The Multifaceted Benefits of Protein Co-expression in Escherichia coli
Published on: February 5, 2015
Multifactorial determinants of protein expression in prokaryotic open reading frames
Malin Allert1, J Colin Cox, Homme W Hellinga
1Department of Biochemistry, Duke University Medical Center, Box 3711, Durham, NC 27710, USA.
Journal of Molecular Biology
|August 24, 2010
Summary
Understanding protein expression requires analyzing open reading frame (ORF) sequences. A new mathematical model predicts expression levels from ORF nucleotide sequences, aiding synthetic biology and heterologous protein production.
Area of Science:
- Molecular Biology
- Bioinformatics
- Synthetic Biology
Background:
- Protein expression levels are influenced by open reading frame (ORF) nucleotide sequences, including codon identity, mRNA secondary structure, and composition.
- Bioinformatic analysis of bacterial genomes shows regional trends in these features.
Purpose of the Study:
- To quantitatively describe the relationship between ORF nucleotide sequences and protein expression levels.
- To develop a predictive model for protein expression based on ORF sequence features.
- To gain mechanistic insight into factors controlling translation efficiency.
Main Methods:
- Designed and synthesized 285 genes with varying ORF features.
- Measured in vitro protein expression levels using Escherichia coli extracts.
- Developed a mathematical function parameterized with synthetic gene data.
Main Results:
- Protein expression is highly dependent on high AU content and low secondary structure in the 5' region of the ORF.
- High-frequency codon usage has a smaller impact on expression.
- AU content in the 3' terminal region has a modest but detectable effect.
Conclusions:
- A predictive model for protein expression from ORF sequences was developed.
- The model provides mechanistic insights into translation initiation, elongation, and termination.
- The findings are applicable to designing synthetic gene systems and optimizing heterologous expression.
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