naphthalene-1,3,6,8-tetrol

CHEBI:18365 EXACT SEEDED

What these status tags mean

Curation status describes a workflow state. SEEDED means the record entered through the source-seeding workflow; it does not imply that no later curation occurred. PROPOSED marks an addition awaiting review; REVIEWED records curator sign-off on identity, structure, filing class and producer claims; DEPRECATED retains a superseded or out-of-scope record. These are workflow decisions, not independently verified human review. Agent-assisted contributions may appear in the record history.

Grounding describes the identifier mapping: EXACT uses an ontology identity asserted by the source; MINTED keeps a local identifier when no defensible ontology identity is available; REVIEW_NEEDED flags an exact structure whose ontology identity needs adjudication. The grounding note retains any unresolved alternatives. These tags do not establish the strength of producer or activity evidence.

A naphthalenetetrol that is naphthalene substituted by hydroxy groups at positions 1, 3, 6 and 8.

Structure

Standard InChIKey	BCMKHWMDTMUUSI-UHFFFAOYSA-N
SMILES	C1=C2C=C(C=C(C2=C(C=C1O)O)O)O
Stereochemistry	fully defined
Cross-references	pubchem:440202

Filing pathway

Polyketides — computed by NPClassifier npclassifier.gnps2.org@2026-09-07, which is why it is pinned rather than recomputed. The gene cluster's asserted class is pks, from MIBiG.

Producer organisms 4

A claim that this taxon makes the compound. The basis says what the evidence addressed — a knockout and a database assertion are not the same claim.

Taxon	Basis	Cluster	Evidence
Nodulisporium sp. ATCC74245 NCBITaxon:96454	SOURCE_ASSERTION	mibig:BGC0001257	PMID:10628853
Glarea lozoyensis NCBITaxon:101852	SOURCE_ASSERTION	mibig:BGC0001258	PMID:12589439
Daldinia eschscholzii IFB-TL01 NCBITaxon:1169046	SOURCE_ASSERTION	mibig:BGC0001906	DOI:10.1039/c8sc03697g
Pyricularia oryzae 70-15 NCBITaxon:242507	SOURCE_ASSERTION	mibig:BGC0002154	PMID:8905089

Occurrences 7

Somebody found the compound in this organism and cited it. That is not a claim that the organism makes it, and nothing here promotes one to the other.

Taxon	Source	Reference
Pyricularia oryzae NCBITaxon:1274781	LOTUS	DOI:10.1146/ANNUREV.MICRO.50.1.491
Streptomyces griseus NCBITaxon:1911	LOTUS	DOI:10.1074/JBC.M110357200
Hypoxylon NCBITaxon:42308	LOTUS	DOI:10.1007/S004380051133
Aspergillus flavus NCBITaxon:5059	LOTUS	DOI:10.1271/BBB.63.820
Aspergillus fumigatus NCBITaxon:746128	LOTUS	DOI:10.1080/13693780802307720
Nodulisporium NCBITaxon:96453	LOTUS	DOI:10.1007/S004380051133
Glarea lozoyensis NCBITaxon:101852	LOTUS	DOI:10.1007/S00438-002-0780-4

Biosynthetic gene clusters 4

Accession	Host	Locus evidence	Genome
mibig:BGC0001257	Nodulisporium sp. ATCC74245 NCBITaxon:96454	CLUSTER_UNSTATED	genbank:AF151533.1
mibig:BGC0001258	Glarea lozoyensis NCBITaxon:101852	CLUSTER_UNSTATED	genbank:AF549411.1
mibig:BGC0001906	Daldinia eschscholzii IFB-TL01 NCBITaxon:1169046	CLUSTER_UNSTATED	genbank:KV884627.1
mibig:BGC0002154	Pyricularia oryzae 70-15 NCBITaxon:242507	CLUSTER_UNSTATED	genbank:CM001232.1

A locus claim and a taxon claim are different questions. Heterologous expression settles the first and leaves the second where the isolation report left it.

Biosynthesis curated

Written by a curator with claim-level evidence on each step; not derived from a source. This is what the rest of the record exists to support.

Step	Enzyme	Reaction	Substrate → product	Evidence
1	NapB2 native NRRL18422 reference UniProtKB:A7KGZ3		CHEBI:18365 → ungrounded	https://github.com/mite-standard/mite_data/blob/6eacd913b2036376031072f69cbb33908f132998/mite_data/data/MITE0000084.json

Step 1: MITE0000084-reported database-proposed oxidation of naphthalene-1,3,6,8-tetrol (CHEBI:18365) to flaviolin by NapB2 (UniProtKB:A7KGZ3, ABS50452.1 on EF397638.1, BGC0001079). Synchronizes biosynthetic_pathway with the existing MITE-backed causal_graph without upgrading producer or locus evidence grades.

Mechanism & Biosynthesis Overview

Causal graph — biosynthesis 4 nodes, 3 edges

Database-proposed NapB2 oxidation consuming exact naphthalene-1,3,6,8-tetrol (THN) to yield flaviolin. MITE explicitly assigns inference from genomic data and chemical structure, not a demonstrated enzyme reaction. Native NRRL18422 reference identity is verified separately. No THN production claim or source-producer/locus transfer is added; not full-record sign-off.

Subject	Predicate	Object	Notes	Evidence
NapB2 native NRRL18422 reference	is_database_proposed_catalyst_of	Database-proposed NapB2 THN oxidation	The enzyme assignment is inferred at source. No primary assay, knockout phenotype, native metal/cofactor occupancy, electron donor, binding site, rate or physical complex is adopted.	https://github.com/mite-standard/mite_data/blob/6eacd913b2036376031072f69cbb33908f132998/mite_data/data/MITE0000084.json https://www.uniprot.org/uniprotkb/A7KGZ3 https://www.ncbi.nlm.nih.gov/protein/ABS50452.1 https://www.ncbi.nlm.nih.gov/nuccore/EF397638.1?from=10400&to=11200 reference https://github.com/mite-standard/mite_data/blob/6eacd913b2036376031072f69cbb33908f132998/mite_data/data/MITE0000084.json evidence type DATABASE_ASSERTION retrieved on 2026-10-07 notes MITE0000084 version1, active, names NapB2/A7KGZ3/ABS50452.1 and BGC0001079. Its THN-to-flaviolin assignment is explicitly inference from genomic data and chemical structure, not demonstrated enzyme activity. Both cited papers were inaccessible; no independently inspected primary assay. snippet Inference from genomic data and chemical structure reference https://www.uniprot.org/uniprotkb/A7KGZ3 evidence type DATABASE_ASSERTION retrieved on 2026-10-07 notes Current TrEMBL28/sequence1,184aa, napB2/taxon270689, direct EMBL EF397638/ABS50452.1 cross-reference. No FUNCTION or catalytic comment. Predicted cupin annotations do not prove THN oxidation. reference https://www.ncbi.nlm.nih.gov/protein/ABS50452.1 evidence type DATABASE_ASSERTION retrieved on 2026-10-07 notes Complete184-residue putative-monooxygenase reference from Streptomyces aculeolatus NRRL18422/taxon270689; full coded_by inspected. Native reference identity is not historical assay-stock proof. reference https://www.ncbi.nlm.nih.gov/nuccore/EF397638.1?from=10400&to=11200 evidence type CURATOR_INFERENCE retrieved on 2026-10-07 notes Complete555-nt plus-CDS10535..11089 in forward801-bp window10400..11200. Codon1/table11 translation equals native annotation, independent ABS50452.1 and current A7KGZ3, all184aa. Absolute coded_by coordinates map to local136..690 and identical DNA; strain/taxon agree. Full-CDS window, not full genome, and identity only, not function.
naphthalene-1,3,6,8-tetrol	is_database_proposed_substrate_of	Database-proposed NapB2 THN oxidation	Pinned example substrate matches owner full key BCMKHWMDTMUUSI-UHFFFAOYSA-N and complete stereo in the repository-helper/RDKit2026.03.5 screen. It is consumed, not synthesized here. Existing name-disagreement and shared-structure discussions remain OPEN; no assay substrate is inferred.	https://github.com/mite-standard/mite_data/blob/6eacd913b2036376031072f69cbb33908f132998/mite_data/data/MITE0000084.json reference https://github.com/mite-standard/mite_data/blob/6eacd913b2036376031072f69cbb33908f132998/mite_data/data/MITE0000084.json evidence type DATABASE_ASSERTION retrieved on 2026-10-07 notes MITE0000084 version1, active, names NapB2/A7KGZ3/ABS50452.1 and BGC0001079. Its THN-to-flaviolin assignment is explicitly inference from genomic data and chemical structure, not demonstrated enzyme activity. Both cited papers were inaccessible; no independently inspected primary assay.
Database-proposed NapB2 THN oxidation	has_database_proposed_product	flaviolin, database-proposed intermediate	MITE names flaviolin and marks the product intermediate. It remains externally ungrounded here; no downstream sequence or pathway finality is adopted. BGC0001079 and the Streptomyces reference are not transferred to the owner's four fungal source producers/loci. SOURCE_ASSERTION/CLUSTER_UNSTATED grades, occurrences and SEEDED status are preserved.	https://github.com/mite-standard/mite_data/blob/6eacd913b2036376031072f69cbb33908f132998/mite_data/data/MITE0000084.json reference https://github.com/mite-standard/mite_data/blob/6eacd913b2036376031072f69cbb33908f132998/mite_data/data/MITE0000084.json evidence type DATABASE_ASSERTION retrieved on 2026-10-07 notes MITE0000084 version1, active, names NapB2/A7KGZ3/ABS50452.1 and BGC0001079. Its THN-to-flaviolin assignment is explicitly inference from genomic data and chemical structure, not demonstrated enzyme activity. Both cited papers were inaccessible; no independently inspected primary assay.

Every edge carries its own citation; an uncited edge is refused by the corpus tests.

Explore across X-Mech

AntibioticMech (naphthalene-1,3,6,8-tetrol) ↗ MediaIngredientMech (CHEBI:18365) ↗ TaxonMech: Nodulisporium sp. ATCC74245 (NCBITaxon:96454) ↗ TaxonMech: Glarea lozoyensis (NCBITaxon:101852) ↗ TaxonMech: Daldinia eschscholzii IFB-TL01 (NCBITaxon:1169046) ↗ TaxonMech: Pyricularia oryzae 70-15 (NCBITaxon:242507) ↗ PathwayMech (mibig:BGC0001257) ↗ PathwayMech (mibig:BGC0001258) ↗ PathwayMech (mibig:BGC0001906) ↗

Open questions 2

name-disagreement — ChEBI calls this structure 'naphthalene-1,3,6,8-tetrol' and MIBiG calls it '1,3,5,8-tetrahydroxynapthalene', '1,3,6,8-tetrahydroxynaphthalene'. They share a Standard InChIKey, so if the names denote different compounds then one upstream record has the wrong structure. Check which.

shared-structure — This structure is reported by more than one MIBiG entry: BGC0001257, BGC0001258, BGC0001906, BGC0002154. Confirm they describe the same compound rather than an upstream cross-reference error.

Provenance

Source concept	Source	Version
BGC0001257	MIBIG	3
BGC0001258	MIBIG	3
BGC0001906	MIBIG	2
BGC0002154	MIBIG	2
CHEBI:18365	CHEBI	3-star

This page is generated from data/natural_products/polyketides/naphthalene-1-3-6-8-tetrol.yaml, which is generated from the committed inventories. Neither is edited by hand.