Columbia team creates Ec19 E. coli with one amino acid partly removed
Updated
Updated · Singularity Hub · May 5
Columbia team creates Ec19 E. coli with one amino acid partly removed
4 articles · Updated · Singularity Hub · May 5
The synthetic bacterium kept altered ribosomes and survived more than 450 generations after researchers removed isoleucine from 21 ribosomal proteins, with AI helping redesign 47 proteins.
Growth was only slightly slower than normal E. coli, suggesting cells may function with a reduced 19-amino-acid alphabet and freeing isoleucine codons for designer amino acids.
The work could aid new medicines, materials and biotechnology, while testing whether modern life's 20-amino-acid code is essential or simply an evolutionary outcome.
What other 'unbreakable' rules of biology will artificial intelligence help us rewrite next?
If life's 20-letter alphabet isn't universal, what could alien biology look like?
Now that AI can rewrite life's basic code, who decides what organisms are ethical to create?
Ec19: The First E. coli Strain Functioning Robustly with Only 19 Amino Acids Through AI-Guided Ribosome Engineering
Overview
In April 2026, a team led by Dr. Harris Wang engineered an E. coli strain, Ec19, that functions with only 19 amino acids by removing isoleucine from its ribosomal proteins. Initial attempts to substitute isoleucine caused a major fitness drop, but advanced AI-driven redesign of 52 ribosomal proteins enabled the creation of Ec19, which maintains over 90% fitness and genetic stability over 450 generations. This removal frees up codons for incorporating non-canonical amino acids, opening new possibilities for programmable biotherapeutics and novel biomaterials. Ec19 also acts as a synthetic auxotroph for isoleucine, providing biocontainment, while supporting evolutionary insights about early life’s simpler amino acid usage. The breakthrough has sparked excitement and raised important ethical and regulatory discussions.