Returns chemical components that are similar to the given chemical component. Results include stereoisomers, components sharing a common scaffold, and molecules with ≥60% PARITY score-based similarity.

Returns aggregated interaction counts for protein-ligand interactions, derived from all PDB structures containing the given chemical component. The response reports how frequently a ligand atom interacts with specific amino-acid residues across the PDB, grouped by interaction type.

Returns the protein chains in PDB entries that interact with the given chemical component and are mapped to UniProt, including the associated UniProt metadata for these proteins.

Returns the amino-acid sequence for a specific PDB Entry and Chain ID (label_asym_id).

Returns information for all bound molecules for a given PDB entry ID, including carbohydrate polymers. Details include each Bound Molecule IDs (e.g: “bm1”, “bm2”), composition (covalently bound ligands with unique CCD IDs) and internal connectivity, or which bound are covalently bound together (e.g: [“F1”, “F6”] means bound ligands identified by author_residue_number “1” and “6” in chain_id “F” are covalently bound).

Returns composition and high-level interactions for a specific Bound Molecule ID (e.g., “bm1”) of a PDB entry ID. This includes its full composition (all covalently linked ligands with their CCD IDs), internal connectivity between those ligands (e.g: [“F1”, “F6”] means bound ligands identified by author_residue_number “1” and “6” in chain_id “F” are covalently bound), and all detected interactions between the bound molecule and surrounding residues or ligands (e.g., covalent, hydrogen-bond, polar, van der Waals, hydrophobic, and atom-plane interactions) calculated for the preferred assembly of the PDB entry.

Returns residue-level sequence conservation data for a specified PDB entry ID and PDB entity ID, including per-residue conservation scores and amino-acid probability distributions.

Returns UniProt mappings for a specific PDB Entity ID, including matched UniProt accessions, residue-level alignment ranges, and metadata identifying the corresponding Best Chain ID for the mapping.

Returns secondary-structure annotations for a specified PDB Entity ID, including helices and strands, plus per-residue structural predictions from external tools (e.g., disorder, folding propensity, flexibility), each with associated scores, labels, and source metadata.

Returns ligand-binding site annotations for a specified PDB entity, including metadata such as Best Chain ID, Scaffold ID, and the total number of protein residues that interact with each ligand (based on ARPEGGIO). For each ligand, the endpoint provides its CCD ID, name, and a list of interacting residues grouped by the Bound Molecule ID they interact with.

Returns protein–protein interface annotations for a specified PDB Entity ID, identifying all residues that form PISA-detected contacts with interacting partner proteins. For each partner, the endpoint provides its UniProt accession, name, and the corresponding interface residue ranges, along with metadata such as the entity’s Best Chain ID.

Returns residue-level functional and biophysical annotations for a specified PDB Entity ID, aggregated from multiple PDBe-KB partner resources (e.g., SASA, hydrophobicity, disorder, flexibility, EM local resolution). Data returned includes annotation type, per-residue scores, confidence metrics, group labels, and the originating resource URL, as well as the Best Chain ID for the entity.

Returns sequence and structural domain annotations for a specified PDB Entity ID, including domain boundaries, identifiers, and names from CATH, SCOP 1.75, Pfam and InterPro domain resources, along with metadata such as the entity’s Best Chain ID.

Returns detailed chain-level annotations for a specified PDB Entity ID, including all of their polymer chains, their residue ranges, and per-residue validation information, along with metadata such as Best Chain ID and author-provided chain identifiers (Obs: chainId in additionalData response refers to struct_asym_id not the author-provided auth_asym_id).

Returns UniProt sequence-variation annotations for a specified PDB Entity ID, remapped to the entity’s residue positions. The response includes each mapped UniProt accession and its variant features, such as variant type, alternative sequence, position, associated evidence, cross-references, clinical or functional annotations, and any available structural-impact metadata.

Returns summarised detailed information about each molecule (or entity in mmcif-speak) in a specified PDB entry, including entity type; molecule names mapped from UniProt; the synonym field (equivalent to _entity.pdbx_description) for polymeric entities; DrugBank-derived synonyms for ligands; sequence data; chain assignments; copy numbers; source organism and sample preparation details; and ligand or chemical component information.

Returns all interface residue contacts calculated by PISA (Proteins, Interfaces, Structures and Assemblies) for a specified PDB entry ID. The results include interaction types (e.g., salt bridges and hydrogen bonds), interatomic distances, and details of the participating atoms and residues from both interacting chains. Results can optionally be filtered by assembly_id and interface_id.

This call returns a summary for the chemical component identified by the given hetcode, including its chemical structure identifiers, physico-chemical descriptors, synonyms, PDB chemical component metadata, functional annotations, and cross-references to external resources.

This call returns a list of PDB entries that contain the given chemical component as defined in the PDB Chemical Component Dictionary. The list includes PDB entries where the component appears either as a standalone chemical component or as part of a larger entity.

These scores are harmonic means of percentile-based quality metrics for macromolecular structures: - geometry_quality: from geometric percentiles (Ramachandran, clashscore, sidechains). - data_quality: from diffraction–data percentiles (R-free, RSRZ). - overall_quality: combines geometry and data percentiles. If any contributing percentile is 0, the harmonic mean is 0. If all percentiles are unavailable, the score is null. experiment_data_available indicates whether experimental diffraction data were used

Provides a validation summary listing key geometric and electron-density–based metrics. For each category (e.g., bonds, angles, RNA suite, Ramachandran, sidechains, RSRZ), the report includes: - number of residues/instances checked - number of outliers - percent outliers - and, where applicable, RMSZ values. Categories with no relevant residues return null percentages.

Lists all geometric and model–data outliers detected by MolProbity, grouped by category (e.g., clashes, sidechains, RSRZ, bond/angle outliers, RNA suite/pucker, chirality, planes, symmetry clashes). Atoms or residues involved in each outlier are reported using unit-id notation The types_of_outliers section summarizes, per residue, which types of outliers it participates in.

Provides a ranked list of PDB structures mapped to the given UniProt accession based on an internal quality score (based on data quality, model quality and resolution ). Each structure entry includes the experimental method, taxonomic origin, resolution, PDB ID and chain, entity and assembly identifiers, observed UniProt alignment segments, model residue ranges, and computed coverage of the UniProt sequence.

Retrieve a list of non-overlapping PDB chains that cover the largest number of observed residues for a given UniProt accession.

Retrieve detailed information on interface residues for a given UniProt accession, including the amino acid sequence for polymeric entities and the total sequence length. The response provides the type of data included and an array of residue-level details, with information such as the starting position in a processed protein sequence when applicable. This endpoint enables analysis of residues involved in protein interfaces, offering sequence context alongside structural and functional annotations.

Retrieve information on interaction partners for a given UniProt accession, including their names, annotations such as antibody roles, the PDB structures where interactions are observed, and whether the interaction is self-directed. This endpoint provides structural and functional context for protein interactions.

Retrieve comprehensive information on PDB structures mapped to a given UniProt accession. The response includes the UniProt sequence and length, along with detailed structure annotations such as entity and chain identifiers, residue coverage in UniProt and PDB numbering, observed regions, mutations, modifications, experiment type, resolution, ligand and entity counts, and supporting metadata like titles, ranking scores, and additional structure-specific information. This endpoint provides an integrated view of how PDB structures align with and represent the UniProt sequence

This call provides PDBe-KB annotations for a given UniProt accession, with optional filtering by annotation category. The response includes the UniProt sequence and length, along with detailed annotation records describing residue ranges in UniProt and PDB numbering, residue codes, associated PDB entries, and supporting metadata such as accession identifiers, scores, confidence levels, and resource links. Information on processed protein start positions is also provided, offering a unified view of structural and functional annotations across the sequence.

Retrieve PDBe-KB sequence conservation data for a UniProt accession. The response provides residue-level conservation scores, per-residue amino acid probability profiles, sequence identifiers, the length of the UniProt sequence, and colors for visualizing main and sub-tracks.

Retrieve variation details for a given UniProt accession. The response includes the protein sequence and length, UniProt identifiers, and a list of variant features with information on alternative sequences, associated diseases, evidences, genomic locations, consequence types, and predictions from tools such as PolyPhen and SIFT. Additional metadata includes clinical significance, source information, cross-references, and relevant URLs, enabling comprehensive analysis of protein sequence variations.

Retrieve text mined annotations for a given UniProt accession. The response includes associated PDB structures, and residue-level annotations. The residue start and end positions follow either UniProt or PDB numbering. Each annotation details the provider, additional supporting data such as citations, entity type, textual evidence, annotator, and AI-generated confidence scores, enabling comprehensive exploration of machine-predicted functional and structural insights.

Provides unified SIFTS residue-level mappings between PDB protein chains (auth_asym_id or struct_asym_id) and all major sequence and domain resources, including UniProt, Pfam, InterPro, CATH, SCOP, GO, Ensembl, and HMMER. Supports both PDB-to-identifier and identifier-to-PDB queries, returning the mapped residue segments and associated annotations for each resource.

Get list of participants and subcomplexes (if any) for the given identifier.

This call returns all PDB entries and RNA chains that map to the specified Rfam accession, including the matched regions.