The Biologically Interesting Molecule Reference Dictionary (BIRD)
Overview
The Biologically Interesting molecule Reference Dictionary (BIRD) contains information about certain biologically interesting molecules in the PDB archive such as peptide-like antibiotics, peptide-like inhibitors, and common oligosaccharides.
BIRD is an external reference file (similar to the Chemical Component Dictionary) that provides information about the chemistry, biology, and structure of these molecules.
BIRD entries include molecular weight and formula, sequence and connectivity, descriptions of structural features and functional classification, natural source (if any), and external references to corresponding UniProt or Norine entries (if applicable).
The entire BIRD resource can be downloaded from the wwPDB FTP area: https://files.wwpdb.org/pub/pdb/data/bird/
BIRD is regularly reviewed for consistency and accuracy. The dictionary is updated each week with new definitions as the corresponding PDB entries are released in the PDB archive. It is used to uniformly annotate PDB entries containing these molecules.
The corresponding BIRD ID code only appears in the PDBx/mmCIF-formatted file of the entry.
BIRD Definition Details
All the components that comprise a BIRD molecule in a PDB entry are listed in the BIRD definition with complete linkages. For example, a modified gramicidin A molecule in PDB entry 1KQE is comprised of two truncated gramicidin A molecules linked by a non-polymer residue (succinic acid). This molecule is fully defined in BIRD (BIRD ID: PRD_000154).
A BIRD molecule may be represented as a polymer with sequence information, as a single ligand with chemical information, or as a branched entity (for oligosaccharides) in a PDB entry. The preferred representation is specified in the BIRD file, along with a representative PDB entry code. All PDB entries containing the same BIRD molecule will have uniform representation. An important feature of BIRD is to provide dual representation of both sequence and chemical information, regardless of the molecular representation in the PDB archive.
Contents of a BIRD entry:
- Molecular presentation in PDB instances: polymer, single molecule, or branched
- Chemical information such as formula and molecular weight
- Structural feature (Type: _pdbx_molecule_features.type) and specific function (Class: _pdbx_molecule_features.class)
- Molecular composition including a list of polymer and non-polymer components
- Sequence information for all representations
- Residue linkages within a polymer/branched chain as well as between a polymer/branched chain and non-polymer components
- Source organism and sequence database reference if available (for naturally occurring BIRD molecules)
Example: information available about BIRD molecules found in the PDB archive is shown using the vancomycin family as an example. The four vancomycin molecules shown below share the same structural feature: glycopeptide (type) and the same functional classification: antibiotics (class). They all contain a peptide core with or without sugar decoration. Click on an image to see a larger version.
- (A) Chloroorienticin A has a disaccharide and a monosaccharide decorating the peptide core (PRD_000203).
- (B) Vancomycin has a disaccharide decorating the peptide core (PRD_000204).
- (C) Vancomycin aglycon has only a peptide core (PRD_000206).
- (D) Desvancosaminyl vancomycin is an intermediate in the vancomycin-biosynthesis pathway. It has one saccharide linked to the peptide core (PRD_000205).
Example of PRD definition for PRD_000203:
data_PRD_000203##_pdbx_reference_molecule.prd_id PRD_000203_pdbx_reference_molecule.name "Chloroorienticin A"_pdbx_reference_molecule.represent_as polymer_pdbx_reference_molecule.type Glycopeptide_pdbx_reference_molecule.type_evidence_code ?_pdbx_reference_molecule.class Antibiotic_pdbx_reference_molecule.class_evidence_code ?_pdbx_reference_molecule.formula "C73 H88 Cl2 N10 O26"_pdbx_reference_molecule.chem_comp_id ?_pdbx_reference_molecule.formula_weight 1592.437_pdbx_reference_molecule.release_status REL_pdbx_reference_molecule.replaces ?_pdbx_reference_molecule.replaced_by ?_pdbx_reference_molecule.compound_details; CHLOROORIENTICIN A IS A TRICYCLIC GLYCOPEPTIDE, A MEMBER OF THE VANCOMYCINFAMILY. THE SCAFFOLD IS A HEPTAPEPTIDE WITH THE CONFIGURATION D-D-L-D-D-L-L.IT IS FURTHER GLYCOSYLATED BY ONE DISACCHARIDE AND ONE MONOSACCHARIDE HERE,CHLOROORIENTICIN A IS REPRESENTED BY GROUPING TOGETHER THE SEQUENCE (SEQRES)AND THE THREE LIGANDS (HET) BGC AND TWO RER.;_pdbx_reference_molecule.description; CHLOROORIENTICIN A IS A TRICYCLIC GLYCOPEPTIDE, GLYCOSYLATED BY ONEDISACCHARIDE ON RESIDUE 4 AND ONE MONOSACCHARIDE ON RESIDUE 6.;_pdbx_reference_molecule.representative_PDB_id_code 1gac##loop__pdbx_reference_entity_list.prd_id_pdbx_reference_entity_list.ref_entity_id_pdbx_reference_entity_list.component_id_pdbx_reference_entity_list.type_pdbx_reference_entity_list.detailsPRD_000203 1 1 polymer "PEPTIDE LIKE SEQUENCE RESIDUES 1 TO 7"PRD_000203 2 2 non-polymer BGCPRD_000203 3 3 non-polymer RERPRD_000203 3 4 non-polymer RER##loop__pdbx_reference_entity_nonpoly.prd_id_pdbx_reference_entity_nonpoly.ref_entity_id_pdbx_reference_entity_nonpoly.name_pdbx_reference_entity_nonpoly.chem_comp_idPRD_000203 2 BETA-D-GLUCOSE BGCPRD_000203 3 VANCOSAMINE RER##loop__pdbx_reference_entity_link.prd_id_pdbx_reference_entity_link.link_id_pdbx_reference_entity_link.link_class_pdbx_reference_entity_link.ref_entity_id_1_pdbx_reference_entity_link.entity_seq_num_1_pdbx_reference_entity_link.comp_id_1_pdbx_reference_entity_link.atom_id_1_pdbx_reference_entity_link.ref_entity_id_2_pdbx_reference_entity_link.entity_seq_num_2_pdbx_reference_entity_link.comp_id_2_pdbx_reference_entity_link.atom_id_2_pdbx_reference_entity_link.value_order_pdbx_reference_entity_link.component_1_pdbx_reference_entity_link.component_2_pdbx_reference_entity_link.detailsPRD_000203 1 PN 1 4 GHP O4 2 ? BGC C1 sing 1 2 ?PRD_000203 2 PN 1 6 OMY ODE 3 ? RER C1 sing 1 4 ?PRD_000203 3 NN 2 ? BGC O2 3 ? RER C1 sing 2 3 ?##loop__pdbx_reference_entity_poly_link.prd_id_pdbx_reference_entity_poly_link.ref_entity_id_pdbx_reference_entity_poly_link.link_id_pdbx_reference_entity_poly_link.atom_id_1_pdbx_reference_entity_poly_link.comp_id_1_pdbx_reference_entity_poly_link.entity_seq_num_1_pdbx_reference_entity_poly_link.atom_id_2_pdbx_reference_entity_poly_link.comp_id_2_pdbx_reference_entity_poly_link.entity_seq_num_2_pdbx_reference_entity_poly_link.value_order_pdbx_reference_entity_poly_link.component_idPRD_000203 1 1 C MLU 1 N OMZ 2 sing 1PRD_000203 1 2 C OMZ 2 N ASN 3 sing 1PRD_000203 1 3 OH OMZ 2 C5 GHP 4 sing 1PRD_000203 1 4 C ASN 3 N GHP 4 sing 1PRD_000203 1 5 C GHP 4 N GHP 5 sing 1PRD_000203 1 6 C3 GHP 4 OCZ OMY 6 sing 1PRD_000203 1 7 C3 GHP 5 CG1 3FG 7 sing 1PRD_000203 1 8 C GHP 5 N OMY 6 sing 1PRD_000203 1 9 C OMY 6 N 3FG 7 sing 1##_pdbx_reference_entity_poly.prd_id PRD_000203_pdbx_reference_entity_poly.ref_entity_id 1_pdbx_reference_entity_poly.db_code NOR00692_pdbx_reference_entity_poly.db_name Norine_pdbx_reference_entity_poly.type peptide-like##_pdbx_reference_entity_sequence.prd_id PRD_000203_pdbx_reference_entity_sequence.ref_entity_id 1_pdbx_reference_entity_sequence.type peptide-like_pdbx_reference_entity_sequence.NRP_flag Y_pdbx_reference_entity_sequence.one_letter_codes LYNFFYF##loop__pdbx_reference_entity_poly_seq.prd_id_pdbx_reference_entity_poly_seq.ref_entity_id_pdbx_reference_entity_poly_seq.num_pdbx_reference_entity_poly_seq.mon_id_pdbx_reference_entity_poly_seq.parent_mon_id_pdbx_reference_entity_poly_seq.hetero_pdbx_reference_entity_poly_seq.observedPRD_000203 1 1 MLU LEU N YPRD_000203 1 2 OMZ TYR N YPRD_000203 1 3 ASN ASN N YPRD_000203 1 4 GHP PHE N YPRD_000203 1 5 GHP PHE N YPRD_000203 1 6 OMY TYR N YPRD_000203 1 7 3FG PHE N Y##loop__pdbx_reference_entity_src_nat.prd_id_pdbx_reference_entity_src_nat.ref_entity_id_pdbx_reference_entity_src_nat.ordinal_pdbx_reference_entity_src_nat.taxid_pdbx_reference_entity_src_nat.organism_scientific_pdbx_reference_entity_src_nat.db_code_pdbx_reference_entity_src_nat.db_namePRD_000203 1 1 31958 "Amycolatopsis orientalis (previouslydesignated Norcardia orientalis and Streptomyces orientalis)"? ?PRD_000203 1 2 31958 "AMYCOLATOPSIS ORIENTALIS" NOR00681Norine##loop__pdbx_prd_audit.prd_id_pdbx_prd_audit.date_pdbx_prd_audit.processing_site_pdbx_prd_audit.action_typePRD_000203 2012-02-08 RCSB "Create molecule"PRD_000203 2012-07-09 PDBe "Other modification"PRD_000203 2012-12-12 RCSB "Initial release"##