Genomically recoded organisms expand biological functions.
Level 5 - mechanism / opinion, no new human data
Basic laboratory/microbiology engineering study (Level 5 by design analogy for non-clinical research).
PubMed 24136966 · doi:10.1126/science.1241459
What was done
Investigators constructed and characterized a genomically recoded organism (GRO) by replacing all known UAG stop codons across the Escherichia coli MG1655 genome with synonymous UAA stop codons. This modification enabled the deletion of release factor 1 (RF1) and the functional reassignment of the UAG codon. The engineered strain was evaluated for nonstandard amino acid incorporation into proteins and susceptibility to T7 bacteriophage infection.
What was found
The recoded E. coli strain allowed deletion of RF1 and functional reassignment of the UAG codon. The resulting GRO exhibited improved properties for incorporating nonstandard amino acids in vivo and showed increased resistance to T7 bacteriophage. The abstract provides no quantitative metrics or effect sizes.
Why it matters
This study demonstrates whole-genome codon reassignment in a living organism, showing that redundant codons can be cleared to expand the chemical repertoire of proteins while conferring viral resistance.
Limits
The abstract reports purely qualitative outcomes without quantitative measurements, statistical values, or growth fitness data. Results are limited to a single engineered laboratory strain of E. coli tested against one bacteriophage (T7).
Cited by
- supports Genomically recoding an organism by altering codons can confer broad viral resistance, which has been experimentally achieved in E. coli.