cittilin A

naturalproductmech:mibig-9e3bd2912f MINTED SEEDED

Grounding review: No 3-star ChEBI entry shares this structure, so the record keeps a content-hashed identifier.

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REVIEWED records curator sign-off on identity, structure, filing class and producer claims; DEPRECATED retains a superseded or out-of-scope record.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.

Structure

Standard InChIKey	WKYLONYSKYXJSJ-UJGPGMDKSA-N
SMILES	CC[C@H](C)[C@@H]1NC(=O)[C@@H](N)CC2=CC(=C(OC)C=C2)C2=C(O)C3=CC(=C2)C[C@H](NC1=O)C(=O)N[C@H](C(=O)O)CC1=CC=C(C=C1)O3
Stereochemistry	fully defined
Cross-references	npatlas:NPA032064

Filing pathway

Amino acids and peptides — 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 ribosomal, from MIBiG.

Producer organisms 1

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
Myxococcus xanthus DK 1622 NCBITaxon:246197	BGC_CHARACTERIZED	mibig:BGC0002043	PMID:32639716

Occurrences 1

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
Myxococcus xanthus NCBITaxon:34	LOTUS	DOI:10.1021/ACSCHEMBIO.0C00430

Biosynthetic gene clusters 1

Accession	Host	Locus evidence	Genome
mibig:BGC0002043	Myxococcus xanthus DK 1622 NCBITaxon:246197	CLUSTER_DEMONSTRATED	genbank:MN731368.1

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	CitC native DK1622 reference UniProtKB:Q1DEH3		naturalproductmech:mibig-5cf4c39e1c → naturalproductmech:mibig-9e3bd2912f	https://github.com/mite-standard/mite_data/blob/6eacd913b2036376031072f69cbb33908f132998/mite_data/data/MITE0000425.json

Step 1: MITE0000425-reported O-methylation of cittilin B to cittilin A by CitC (UniProtKB:Q1DEH3, QLH55580.1 on MN731368.1, BGC0002043; DK1622 locus MXAN_0682 / ABF85961.1 on CP000113.1). 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

MITE-reported CitC O-methylation of cittilin B to cittilin A. The native Myxococcus xanthus DK1622 reference is sequence-verified independently; current UniProt supports identity, not a compound-specific activity assertion. Both neutral compound forms match the exact database example. No primary assay, CitB/MxPep step, native cofactor state or pathway finality is inferred; not full-record sign-off.

Subject	Predicate	Object	Notes	Evidence
CitC native DK1622 reference	is_database_reported_catalyst_of	MITE-reported CitC O-methylation	MITE supplies the functional attribution; reference translation establishes identity only. No primary assay, rate, knockout phenotype, native cofactor state, site or physical complex is adopted. Automated ubiquinone/mitochondrial family labels are not cittilin chemistry.	https://github.com/mite-standard/mite_data/blob/6eacd913b2036376031072f69cbb33908f132998/mite_data/data/MITE0000425.json https://www.uniprot.org/uniprotkb/Q1DEH3 https://www.uniprot.org/uniparc/UPI00004FDDBF https://www.ncbi.nlm.nih.gov/protein/QLH55580.1 https://www.ncbi.nlm.nih.gov/nuccore/MN731368.1 reference https://github.com/mite-standard/mite_data/blob/6eacd913b2036376031072f69cbb33908f132998/mite_data/data/MITE0000425.json evidence type DATABASE_ASSERTION retrieved on 2026-10-07 notes MITE0000425 version 1, active, identifies CitC, QLH55580.1/UniParc UPI00004FDDBF and BGC0002043, and assigns O-methylation of cittilin B to yield cittilin A. Its heterologous-expression and in-vitro codes are database assertions: the cited primary paper was inaccessible. No specific assay, kinetic or native cofactor claim is adopted. snippet CitC specifically methylates cittilin B reference https://www.uniprot.org/uniprotkb/Q1DEH3 evidence type DATABASE_ASSERTION retrieved on 2026-10-07 notes Current TrEMBL entry103, sequence1,204aa, MXAN_0682/taxon246197, predicted protein existence, no FUNCTION or catalytic-activity comment. The generic methyltransferase-domain name and automated keywords are not independent cittilin evidence. Entry cross-links CP000113/ABF85961.1, not directly MN731368/QLH55580.1; exact full sequence, strain and UniParc provide the mapping. reference https://www.uniprot.org/uniparc/UPI00004FDDBF evidence type DATABASE_ASSERTION retrieved on 2026-10-07 notes Retained full sequence archive links active Q1DEH3 and QLH55580 to the same204-residue DK1622 reference. Inactive UniProt entries and other-strain identical sequences are not selected as tested examples. UniParc is not a UniProtKB accession. reference https://www.ncbi.nlm.nih.gov/protein/QLH55580.1 evidence type DATABASE_ASSERTION retrieved on 2026-10-07 notes Complete independent GenPept methyltransferase record and coded_by inspected:204aa, M.xanthus DK1622/taxon246197; no named CitC gene qualifier is required to replace the exact protein mapping. reference https://www.ncbi.nlm.nih.gov/nuccore/MN731368.1 evidence type CURATOR_INFERENCE retrieved on 2026-10-07 notes Complete615-nt plus-strand CDS12819..13433, codon1/table11, translates exactly to annotation, independent QLH55580.1, UniParc and current Q1DEH3, all204aa. Independent coded_by DNA/coordinates and genomic/source strain DK1622/taxon246197 match. No separate ABF85961.1/CP000113 native-CDS check or historical assay-stock/construct identity is claimed.
cittilin B	is_database_reported_substrate_of	MITE-reported CitC O-methylation	Pinned MITE substrate matches the cittilin B owner's full InChIKey LRYMXYNLAMRRTH-CIWZQKDMSA-N and complete stereo in the retained repository-helper/RDKit2026.03.5 screen. This grounds the exact neutral substrate, not a precursor-peptide or different congener. The separate cittilin B owner and its occurrences remain unchanged.	https://github.com/mite-standard/mite_data/blob/6eacd913b2036376031072f69cbb33908f132998/mite_data/data/MITE0000425.json reference https://github.com/mite-standard/mite_data/blob/6eacd913b2036376031072f69cbb33908f132998/mite_data/data/MITE0000425.json evidence type DATABASE_ASSERTION retrieved on 2026-10-07 notes MITE0000425 version 1, active, identifies CitC, QLH55580.1/UniParc UPI00004FDDBF and BGC0002043, and assigns O-methylation of cittilin B to yield cittilin A. Its heterologous-expression and in-vitro codes are database assertions: the cited primary paper was inaccessible. No specific assay, kinetic or native cofactor claim is adopted.
MITE-reported CitC O-methylation	has_database_reported_product	cittilin A	Pinned MITE product matches owner full InChIKey WKYLONYSKYXJSJ-UJGPGMDKSA-N and complete stereo in the retained repository-helper/RDKit2026.03.5 screen. No pathway finality or primary assay inference. Existing BGC_CHARACTERIZED/CLUSTER_DEMONSTRATED source grades, all source fields and SEEDED status are preserved, not independently upgraded by this graph.	https://github.com/mite-standard/mite_data/blob/6eacd913b2036376031072f69cbb33908f132998/mite_data/data/MITE0000425.json reference https://github.com/mite-standard/mite_data/blob/6eacd913b2036376031072f69cbb33908f132998/mite_data/data/MITE0000425.json evidence type DATABASE_ASSERTION retrieved on 2026-10-07 notes MITE0000425 version 1, active, identifies CitC, QLH55580.1/UniParc UPI00004FDDBF and BGC0002043, and assigns O-methylation of cittilin B to yield cittilin A. Its heterologous-expression and in-vitro codes are database assertions: the cited primary paper was inaccessible. No specific assay, kinetic or native cofactor claim is adopted.

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

Explore across X-Mech

AntibioticMech (cittilin A) ↗ MediaIngredientMech (naturalproductmech:mibig-9e3bd2912f) ↗ TaxonMech: Myxococcus xanthus DK 1622 (NCBITaxon:246197) ↗ PathwayMech (mibig:BGC0002043) ↗

Provenance

Source concept	Source	Version
BGC0002043	MIBIG	3

This page is generated from data/natural_products/amino_acids_and_peptides/cittilin-a.yaml, which is generated from the committed inventories. Neither is edited by hand.