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# Structural basis of transcription of the hachimoji eight-letter alphabet by E. coli RNA polymerase

## Details

**Authors** Li et al.

**Year** 2026

**Publisher** Nature Communications

**Discipline** Genetics

**Secondary disciplines** Chemistry

[Read it at the publisher](https://doi.org/10.1038/s41467-026-76668-0) 
10.1038/s41467-026-76668-0

## In authors' words

### What they found (results)

Cryo-electron microscopy structures show E. coli RNA polymerase transcribes a synthetic eight-letter (hachimoji) genetic alphabet using largely the same biochemical and structural recognition signals it uses for the natural four-letter code, rather than requiring new recognition machinery.

## Commentary

### In short

The presumed boundary between 'natural' and 'synthetic' genetic building blocks collapses at the mechanistic level: the same whole-enzyme recognition architecture, unchanged since it evolved to read four letters, turns out to generalize to an expanded set of parts without needing new machinery.

**Patterns it shows** D, S

**Added** 2026-09-07

**How to cite this** Li et al. (2026). Structural basis of transcription of the hachimoji eight-letter alphabet by E. coli RNA polymerase. Nature Communications.