Claude cracks the 3D structure of Vault particles, Anthropic says

On November 5, 2026, Anthropic announced that its biology research team, working with Claude, had determined the first three-dimensional structure of a Vault particle associated with prokaryotes. Vaults are vesicle-like protein complexes and among the largest ribonucleoprotein particles inside cells. Human cells carry roughly 10,000 of them, typically about 67 nanometers long and 40 nanometers wide. They were first discovered in 1986, yet their biological function has remained unknown for around 40 years.

The team searched for homologs of the major vault protein (MVP) across some 15 billion predicted protein sequences, finding candidates in 29 bacterial phyla and 4 archaeal phyla, and selected 44 proteins for laboratory testing. Of these, seven proteins expressed in E. coli assembled into vault-like particles, and cryo-electron microscopy confirmed the complete closed structure of four candidates: two from bacteria and two from phage.

The work focused on the phage-derived L05 vault particle, resolved at 3.2 angstroms. It consists of 96 identical protein chains, with a total molecular mass of about 9.5 MDa and an internal volume roughly 25 percent larger than the counterpart found in human cells. Using AI to screen candidate proteins among vast numbers of sequences cut laboratory purification time from a traditional 3 days to 90 minutes. So far the finding rests on Anthropic's own announcement, and claims that it is the first such structure await outside verification; further developments are still to be seen.