Claude Agents Discover Novel ART Enzyme System in Bacteriophages

Anthropic published a pre-print describing ART (array-associated reverse transcriptases), a previously uncharacterized enzyme system found in bacteriophages, identified by Claude AI agents running autonomously. The discovery is the first result from Anthropic's new molecular biology group and wet lab. In a 21.5-hour campaign without human input, 949 agent sessions processed 215.6 million tokens and searched 1.94 billion protein clusters. The agents recovered roughly 200,000 reverse transcriptase clusters, scored 3,564 candidate partner families, and produced 19 human-readable reports. One report flagged a long array of evenly spaced DNA repeats beside an enzyme gene, a pattern resembling a CRISPR array. Anthropic named the family ART, comprising a reverse transcriptase, a partner gene, and the repeat array. Lab tests confirmed the array is transcribed as distinct short RNAs, comprising up to 8% of a Staphylococcus phage's RNA 15 minutes after infection. The team has not yet demonstrated that the enzyme is active or that it acts on those RNAs, and the findings have not been peer reviewed. Anthropic published the pre-print early to showcase Claude's scientific discovery capabilities and invite collaboration.