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Mapping Bacterial Functional Networks and Pathways in Escherichia Coli using Synthetic Genetic Arrays
Published on: November 12, 2012
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Probing the limits of genetic recoding in essential genes
M J Lajoie1, S Kosuri, J A Mosberg
1Department of Genetics, Harvard Medical School, Boston, MA 02115, USA.
Science (New York, N.Y.)
|October 19, 2013
Summary
Radically altering the genetic code by removing rare codons from essential genes in Escherichia coli is feasible. However, genome design constraints highlight the need for rapid prototyping and testing of genetic code modifications.
Area of Science:
- Synthetic Biology
- Genetic Engineering
- Microbial Biotechnology
Background:
- Radically altering genetic codes enables engineered organisms with novel chemical capabilities and biological containment.
- Previous work involved reassigning the UAG stop codon, but modifying prevalent sense codons presents greater challenges due to their regulatory roles in gene expression.
Purpose of the Study:
- To assess the feasibility of radically altering the genetic code by modifying essential genes.
- To investigate the challenges and constraints associated with genome-wide codon reassignment.
Main Methods:
- Selected 42 highly expressed essential genes in Escherichia coli for modification.
- Removed all instances of 13 rare codons from these selected genes.
- Attempted to shuffle all remaining codons across 80 engineered E. coli strains.
Main Results:
- Demonstrated the feasibility of genome-wide removal of 13 specific codons from essential genes.
- Identified several genome design constraints that impact the process of genetic code alteration.
Conclusions:
- Genome-wide codon removal is achievable, but requires careful consideration of design limitations.
- Emphasizes the necessity of rapid prototyping and iterative testing strategies for engineering complex genetic modifications.
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