All families / PF18902
PF18902: DUF5658
Domain of unknown function (DUF5658)
- Curation status
- SEEDED
- Seed status
- UNKNOWN CANDIDATE
- Characterization
- UNSCORED
Grounding
PF18902: Domain of unknown function (DUF5658)
IPR043717: integrated entry for Domain of unknown function (DUF5658)
Source description
This family of proteins is found in bacteria, archaea and viruses. Proteins in this family are typically between 101 and 135 amino acids in length. There is a completely conserved aspartate and a conserved EXNP motif that may be functionally important. These and others residues form a deep pocket that may bind to an as yet unidentified ligand. This family is related to PF01889 (Archaeal lipoprotein biogenesis component AliA/AliB-like).
Evidence and references
Source descriptions and links are provenance, not independent functional validation.
Evidence counts: not scored.
Curated functional assertions
No curated functional assertions supplied.
Protein sequence examples
3 verified sequence examples. FASTA
| UniProt | Protein / organism | Sequence | Provenance |
|---|---|---|---|
| O28934 | Uncharacterized protein AF_1335 Archaeoglobus fulgidus (strain ATCC 49558 / DSM 4304 / JCM 9628 / NBRC 100126 / VC-16) | 156 aa; version 1 UniProt 2026_03 | UNIPROT FETCH1 sibling references |
| P20206 | Uncharacterized protein C-102a Sulfolobus spindle-shape virus 1 | 102 aa; version 1 UniProt 2026_03 | UNIPROT FETCH1 sibling references |
| Q25BI2 | Putative transmembrane protein ORF13 His1 virus (isolate Australia/Victoria) | 99 aa; version 1 UniProt 2026_03 | UNIPROT FETCH1 sibling references |
Pfam membership is not functional evidence. Whole-protein sequences do not establish domain boundaries. A coverage gap here is not absence from UniProt.
Sequences and metadata: UniProt Consortium, CC BY 4.0.
Domain matches
No residue-level domain match evidence is available in this build. Structure and AlphaFold counters do not supply coordinates or establish function.
Snapshot counters
- proteins
- 1,225
- matches
- 1,225
- proteomes
- 872
- taxa
- 1,602
- structures
- 0
- alphafold models
- 986
- domain architectures
- 4
Classification basis
short name matches duf; name says unknown function; domain of unknown function
No scoring reasons supplied.
Related Mech records
| Family | Mech | Record | Protein | Link basis |
|---|---|---|---|---|
| DUF5658 (PF18902) | ProteinTraitsMech | Domain of unknown function DUF5658 | trait identifier | |
| DUF5658 (PF18902) | ProteinTraitsMech | Domain of unknown function (DUF5658) | O28934 Uncharacterized protein AF_1335 | canonical example family classification |
| DUF5658 (PF18902) | ProteinTraitsMech | Domain of unknown function (DUF5658) | P20206 Uncharacterized protein C-102a | canonical example family classification |
| DUF5658 (PF18902) | ProteinTraitsMech | Domain of unknown function (DUF5658) | Q25BI2 Putative transmembrane protein ORF13 | canonical example family classification |
| DUF5658 (PF18902) | ProteinTraitsMech | Domain of unknown function (DUF5658) | trait identifier |
Curation history and reviews
No retained curation events supplied.
No retained review supplied.
Record source
Status and evidence
- Seed status
- A name-based classification of frozen InterPro/Pfam metadata. UNKNOWN CANDIDATE means the metadata explicitly says the function is unknown. KNOWN HISTORICAL DUF means a DUF name matched without that wording; this heuristic is not proof of a known function and does not establish experimental characterization. EX DUF means Pfam renamed the family away from a DUF/UPF name, as recorded in Pfam's previous identifiers; a rename usually follows published work on some members but is naming history, not proof of function for every member. Some EX DUF families' current names or descriptions still say the function is unknown; their classification basis lists this, and scoring does not treat them as characterized. FALSE POSITIVE TEXT HIT means the naming rules did not match.
- Characterization
- A separate evidence-scoring result. UNSCORED means no score has been calculated; it is not evidence that the family lacks a known function. Missing scores are not negative evidence. PARTIALLY CHARACTERIZED has partial support; KNOWN HISTORICAL DUF can inherit the seed label or reflect a known-function signal. Neither label implies experimental validation.
- Evidence counts
- Source-specific signals, not unique proteins, publications, or confidence scores. Known counts Rhea reactions and experimentally supported GO molecular-function annotations. Partial counts functional/domain assignments. Context counts structural, environmental, orthology, interaction and neighborhood signals; context alone does not assign function. Repeated annotations may not be independent.
- Curation status
- Reported separately from seed classification and characterization. SNAPSHOT ONLY means no curated metadata was supplied for this build. SEEDED denotes a source-derived record, not an expert-reviewed functional claim.
- Missing counts
- Not available means the source did not supply that counter. A zero is a reported count. Not scored means evidence counts are unavailable.