Scientists in London have assembled and “re-coded” the E. coli genome. The lab eliminated redundant codons, using 59 (rather than 61) codons to produce all 20 amino acids and 2 (rather than 3) stop codons. The changes required over 18,000 replacements. Similar efforts have generally resulted in cell death, but the group’s synthetic bacteria are living and reproducing. Eliminating redundant codons may allow new functions to be assigned to those sequences and could enable novel protein synthesis.