Cited by 2,596Protein Structure and DynamicsEnzyme Structure and FunctionMachine Learning in Bioinformatics

The DOI matches its Crossref record; 48 of the 48 references it cites were found in a registry or an index; none of the 22 sources its claims cite is checked for support yet.

Fast and accurate protein structure search with Foldseek

Open access

Published version of a preprint

Abstract

As structure prediction methods are generating millions of publicly available protein structures, searching these databases is becoming a bottleneck. Foldseek aligns the structure of a query protein against a database by describing tertiary amino acid interactions within proteins as sequences over a structural alphabet. Foldseek decreases computation times by four to five orders of magnitude with 86%, 88% and 133% of the sensitivities of Dali, TM-align and CE, respectively.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

Foldseek encodes protein tertiary interactions as sequences over a 20-state 3Di structural alphabet and searches them with MMseqs2-derived prefilters and alignment modules. It reduces structure-search computation times by four to five orders of magnitude while retaining 86%, 88% and 133% of the sensitivities of Dali, TM-align and CE, respectively.

Key findings

  • Foldseek decreases computation times by four to five orders of magnitude with 86%, 88% and 133% of the sensitivities of Dali, TM-align and CE, respectively.
  • On SCOPe40 all-versus-all searches, Foldseek is more than 4,000 times faster than TM-align and Dali and over 21,000 times faster than CE; on AlphaFoldDB (version 1), it is around 184,600 and 23,000 times faster than Dali and TM-align, respectively.
  • In precision-recall analysis, Foldseek-TM and Foldseek have the highest and third-highest area under the precision-recall curve on family, superfamily and fold levels; Foldseek-TM improves over TM-align because its prefilter suppresses high-scoring false positives.
  • For SARS-CoV-2 RdRp (PDB: 6M71, chain A; 942 residues) searched in AlphaFoldDB (version 1), search times were 10 d for Dali, 33 h for TM-align and 6 s for Foldseek, making it 180,000 and 23,000 times faster; all top 10 hits were known RdRp homologs.

Methods

  • Foldseek discretizes structures into 3Di sequences describing each residue’s geometric conformation with its spatially closest residue, then uses MMseqs2’s double-diagonal k-mer and gapless alignment prefilters followed by SIMD-accelerated Smith–Waterman local alignment combining 3Di and amino acid substitution scores; an optional global TM-align mode is also provided.
  • Benchmarks include SCOPe40 (11,211 non-redundant single-domain structures) all-versus-all, AlphaFoldDB (version 1) clustered to 34,270 structures with 100 randomly selected queries for reference-free multi-domain tests, and HOMSTRAD (1,032 protein families); runtime evaluations used an AMD EPYC 7702P 64-core CPU.
  • Sensitivity was measured as the fraction of true positives before the first false positive, with AUROC/ROC1 and precision-recall analyses; multi-domain benchmarks used LDDT thresholds of at least 0.6 for true positives and below 0.25 for false positives, ignoring matches in between.

Limitations

  • The paper states that the SCOPe benchmark uses only single-domain proteins as queries and targets, so it cannot assess local similarities such as homologous domains shared between multi-domain proteins; the HOMSTRAD alignment benchmark has the same limitation, as most HOMSTRAD proteins are single-domain (median length 182 residues).
  • The paper states that the reference-free multi-domain benchmark requires choosing thresholds for true and false positives.
  • The text makes evident that the 3Di alphabet and substitution matrix were trained and cross-validated on SCOPe40, and that methods likely overfitted on SCOPe due to data leakage were excluded from benchmark comparison; the paper reports no overfitting despite training 492 parameters.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1038/s41587-023-01773-0

Cites

48 of 48 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Figures

Fig. 1 Foldseek workflow. a, Foldseek searches a set of query structures through a set of target structures. (1) Query and target structures are discretized into 3Di sequences (see b). To detect candidate structures, we apply the fast and sensitive k-mer and ungapped alignment prefilter of MMseqs2 to the 3Di sequences, (2) followed by vectorized Smith–Waterman local alignment combining 3Di and amino acid substitution scores. Alternatively, a global alignment is computed with a 1.7-times accelerated TM-align version (Supplementary Fig. 12). b, Learning the 3Di alphabet. (1) 3Di states describe tertiary interaction between a residue i and its nearest neighbor j. Nearest neighbors have the closest virtual center distance (yellow). Virtual center positions (Supplementary Fig. 1) were optimized for maximum search sensitivity. (2) To describe the interaction geometry of residues i and j, we extract seven angles, the Euclidean Cα distance and two sequence distance features from the six Cα coordinates of the two backbone fragments (blue and red). (3) These 10 features are used to define 20 3Di states by training a VQ-VAE28 modified to learn states that are maximally evolutionary conserved. For structure searches, the encoder predicts the best-matching 3Di state for each residue.
Fig. 1 Foldseek workflow. a, Foldseek searches a set of query structures through a set of target structures. (1) Query and target structures are discretized into 3Di sequences (see b). To detect candidate structures, we apply the fast and sensitive k-mer and ungapped alignment prefilter of MMseqs2 to the 3Di sequences, (2) followed by vectorized Smith–Waterman local alignment combining 3Di and amino acid substitution scores. Alternatively, a global alignment is computed with a 1.7-times accelerated TM-align version (Supplementary Fig. 12). b, Learning the 3Di alphabet. (1) 3Di states describe tertiary interaction between a residue i and its nearest neighbor j. Nearest neighbors have the closest virtual center distance (yellow). Virtual center positions (Supplementary Fig. 1) were optimized for maximum search sensitivity. (2) To describe the interaction geometry of residues i and j, we extract seven angles, the Euclidean Cα distance and two sequence distance features from the six Cα coordinates of the two backbone fragments (blue and red). (3) These 10 features are used to define 20 3Di states by training a VQ-VAE28 modified to learn states that are maximally evolutionary conserved. For structure searches, the encoder predicts the best-matching 3Di state for each residue.CC BY · PubMed Central
Fig. 2 Foldseek reaches similar sensitivities as structural aligners at thousands of times their speed. a, Cumulative distributions of sensitivity for homology detection on the SCOPe40 database of single-domain structures. TPs are matches within the same superfamily; FPs are matches between different folds. Sensitivity is the area under the ROC (AUROC) curve up to the first FP (see Supplementary Fig. 4 for family and fold). b, Precision-recall curve of SCOPe40 superfamilies (see Supplementary Fig. 4 for family and fold). c, Average sensitivity up to the first FP for family, superfamily and fold versus total runtime on an AMD EPYC 7702P 64-core CPU for the all-versus-all searches of 11,211 structures of SCOPe40. d, Search sensitivity on multi-domain, full-length AlphaFold2 protein models. One hundred queries, randomly selected from AlphaFoldDB (version 1), were searched against this database. Per-residue query coverage (y axis) is the fraction of residues covered by at least x (x axis) TP matches ranked before the first FP match. e, Alignment quality for alignments of AlphaFoldDB (version 1) protein models (top panel), averaged over the top five matches of each of the 100 queries. Sensitivity = TP residues in alignment / query length; precision = TP residues / alignment length. Reference-based alignment quality benchmark on HOMSTRAD alignments. f, Alignment quality comparison between Foldseek and Dali for each HOMSTRAD family. The F1 score is the harmonic mean between sensitivity and precision.
Fig. 2 Foldseek reaches similar sensitivities as structural aligners at thousands of times their speed. a, Cumulative distributions of sensitivity for homology detection on the SCOPe40 database of single-domain structures. TPs are matches within the same superfamily; FPs are matches between different folds. Sensitivity is the area under the ROC (AUROC) curve up to the first FP (see Supplementary Fig. 4 for family and fold). b, Precision-recall curve of SCOPe40 superfamilies (see Supplementary Fig. 4 for family and fold). c, Average sensitivity up to the first FP for family, superfamily and fold versus total runtime on an AMD EPYC 7702P 64-core CPU for the all-versus-all searches of 11,211 structures of SCOPe40. d, Search sensitivity on multi-domain, full-length AlphaFold2 protein models. One hundred queries, randomly selected from AlphaFoldDB (version 1), were searched against this database. Per-residue query coverage (y axis) is the fraction of residues covered by at least x (x axis) TP matches ranked before the first FP match. e, Alignment quality for alignments of AlphaFoldDB (version 1) protein models (top panel), averaged over the top five matches of each of the 100 queries. Sensitivity = TP residues in alignment / query length; precision = TP residues / alignment length. Reference-based alignment quality benchmark on HOMSTRAD alignments. f, Alignment quality comparison between Foldseek and Dali for each HOMSTRAD family. The F1 score is the harmonic mean between sensitivity and precision.CC BY · PubMed Central

Verification

Claims the paper makes

26 Own result · 18 Not checked yet · 13 Own interpretation · 8 No basis given · 2 Own method

Verify all 22 references — free account

Show all 31 claims

  • It may state two separate claims as one. 22
  • Probably not a substantial claim. 17
36 of 36
  • The paper relies on this without support.

    The SCOPe40 dataset is a suitable benchmark for evaluating protein structure search sensitivity.

    “The SCOPe benchmark set consists of single domains with an average length of 174 residues.”
  • The paper relies on this without support.

    The HOMSTRAD pairwise alignments are accurate reference alignments for measuring alignment quality.

    “With the HOMSTRAD alignments as reference, we measured for each pairwise alignment the sensitivity (fraction of residue pairs of the HOMSTRAD alignment that were correctly aligned) and the precision (fraction of correctly aligned residue pairs in the predicted alignment).”
  • The paper relies on this without support.

    The ESM Atlas API can accurately predict structures of user-supplied sequences up to 400 residues.

    “We use the ESM Atlas API to predict structures of user-supplied sequences that are, at most, 400 residues long.”
  • The paper relies on this without support.

    The virtual center parameters optimized on SCOPe generalize to other datasets.

    “The virtual center defined by θ = 270∘, τ = 0∘ and l = 2 performed best in the SCOPe benchmark.”
4 of 4

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Citations

Cites

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Research works printed but not linked: 1

  1. Van den Oord, A., Vinyals, O. & Kavukcuoglu, K. Neural discrete representation learning. Proc. of the 31st Conference on Neural Information Processing Systems. https://proceedings.neurips.cc/paper_files/paper/2017/file/7a98af17e63a0ac09ce2e96d03992fbc-Paper.pdf (NIPS, 2017).

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Metadata

Authors
van Kempen, M., Kim, S. S., Tumescheit, C., Mirdita, M., Lee, J., Gilchrist, C. L. M., Söding, J., & Steinegger, M.
Affiliations
  • Seoul National University (KR)
  • Max Planck Institute for Multidisciplinary Sciences (DE)
Corresponding author
  • Söding, Johannes
  • Steinegger, Martin
Venue
Nature Biotechnology
Published
2023-05-08
Volume
42
Issue
2
Pages
243-246
ISSN
  • 0733-222X (ISSN-L)
  • 1087-0156
  • 1546-1696
OpenAlex
W4375858802
Cited by
2,596
References
48
Citations by year
2026: 828 · 2025: 917 · 2024: 592 · 2023: 211
FWCI
227.22
Type
journal article
Language
en
Open access
Locations
  • Nature Biotechnology (publishedVersion, cc-by)
  • bioRxiv (Cold Spring Harbor Laboratory) (acceptedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • MPG.PuRe (Max Planck Society) (submittedVersion, other-oa)
  • GoeScholar The Publication Server of the Georg-August-Universität Göttingen (Georg-August-Universität Göttingen) (submittedVersion, cc-by)
  • Seoul National University Open Repository (Seoul National University) (submittedVersion)
Funders
  • National Research Foundation of Korea (2019R1-A6A1-A10073437, 2019R1A6A1A10073437, 2020M3A9G7103933, 2021R1C1C102065, 2021M3A9I4021220)
  • German ministry for education and research (BMBF)
  • Samsung DS research fund, Creative-Pioneering Researchers Program through Seoul National University
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Protein Structure and Dynamics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Structural Biology › Enzyme Structure and Function
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Machine Learning in Bioinformatics
Keywords
protein structure search, Foldseek, structural alignment, structural alphabet, protein structure database, computational efficiency
MeSH terms
Algorithms, Amino Acids, Proteins, Software, Databases, Protein

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