esmc

name	esmc
description	ESM C / ESM Cambrian (ESMC) — next-generation protein representation language models scaling beyond ESM-2 (300M / 600M open weights; larger tiers may need Forge/API). Use when: (1) Stronger AA embeddings than ESM-2 for metagenomic proteins, (2) Representation learning (not ESM3-style controllable generation), (3) Downstream heads that benefit from Cambrian checkpoints. Upstream: https://github.com/evolutionaryscale/esm (Biohub/esm). Route via protein-language-model. Keep ESM-2 workflows on esm when pinned for reproducibility.
license	MIT
category	analysis-tools
tags	["ESMC","ESM-C","ESM-Cambrian","PLM","protein-language-model","EvolutionaryScale"]
upstream	https://github.com/evolutionaryscale/esm
stage	function

ESM C (ESM Cambrian / ESMC)

Upstream: evolutionaryscale/esm · Blog: https://www.evolutionaryscale.ai/blog/esm-cambrian · Biohub: https://biohub.org/blog/esm-cambrian-unsupervised-learning

Citation

Candido, S. et al. Language Modeling Materializes a World Model of Protein Biology. bioRxiv https://doi.org/10.64898/2026.06.03.729735 (2026).

Interim blog (if preprint not yet cited in Methods): ESM Team. ESM Cambrian: Revealing the mysteries of proteins with unsupervised learning (2024). https://www.evolutionaryscale.ai/blog/esm-cambrian

See also docs/references.md.

Analytical thinking

ESM C is the representation-learning sibling of generative ESM3. It targets embeddings / biological understanding with a new scaling frontier vs ESM-2. Open weights commonly discussed: 300M and 600M; larger (e.g. 6B) tiers may require Forge / commercial endpoints — pin license and access path.

vs	Prefer ESMC when
esm (ESM-2)	New embedding jobs that can adopt Cambrian checkpoints
saprot	Sequence-only representation; not Foldseek SA-token PLM
prostt5	Embeddings / property heads — not AA↔3Di for Foldseek DB build
ESM3	Representation vs multimodal controllable generation

Do not silently swap ESM-2 for ESMC in published PLMSearch/LucaPhylo-style pipelines without re-benchmarking. Check academic vs commercial terms for each size.

How to run

# install current EvolutionaryScale / Biohub esm package per upstream README
# typical: load esmc_300m / esmc_600m (exact IDs change — verify README tag)
# embed sequences → mean / per-residue vectors for clustering or classifiers

Do not invent API method names — follow the installed esm package docs.

Decision tree

Need modern protein embeddings?
├─ ESM C / Cambrian checkpoints → esmc
├─ Legacy / pinned ESM-2 pipelines → esm
├─ Structure-aware AA+3Di tokens → saprot
├─ Foldseek 3Di from FASTA → prostt5
└─ Remote homology wrappers → plmsearch / deepblast

Related skills

protein-language-model · esm · saprot · prostt5 · plmsearch · deepblast · foldseek · metagenomics-llm · tool-selection