Anthropic: Claude helped map first prokaryote-side vault particle 3D structure

Verified against Anthropic’s research page Investigating vault particles with Claude (published Nov 4, 2026) and its official account note:

What they report
Vault particles are large hollow protein barrels discovered in 1986; their function is still unknown. They were previously known mainly in eukaryotic cells. Anthropic’s biology team says it used cryo-EM to resolve a vault built from bacteriophage protein L05: 96 copies (48 per half), about 9.5 megadaltons, roughly 54 nm long by 45 nm wide. Related proteins had been noted in bacterial and phage genomes, but Anthropic says that, to its knowledge, no one had shown they assemble into vaults.

Claude’s role (company description)
Under human direction, Claude searched ~15 billion predicted protein sequences, designed DNA constructs, helped optimize isolation, and processed microscopy data. Anthropic writes that a purification that conventionally takes about three days took ~90 minutes after their optimization, and a first structural model was ready in ~34 hours versus an estimated weeks of manual work. The piece also documents Claude mistakes (for example a growth-medium additive and a skipped standard cryo-EM step that produced a flawed map) and collaboration with ML researchers to address them.

Limits and next steps
Anthropic states it has not determined biological function; particles were made only in E. coli so far and have not been tested in native bacterial/phage hosts. A preprint was submitted to bioRxiv (link to be updated when live); structures and more data are planned for release soon.

This is a faithful paraphrase of the official research page and announcement; no independent verification or function claims are added.

• Investigating vault particles with Claude
• Anthropic official post