Manganese element Critical Material
The element Mn, distinct from its dissolved oxidation states, ligand complexes, oxide minerals, and Mn-bearing commodities. The US designation below maps to the explicitly named manganese commodity in the 2025 list; it does not assign criticality to every Mn-bearing compound or resource.
Identifiers & Classification
| System | Identifier | Label |
|---|---|---|
| CHEBI |
CHEBI:18291
|
manganese atom |
Criticality Designations
| Jurisdiction | List Name | Edition / Document | Classification | Source |
|---|---|---|---|---|
| United States of America | USGS Final List of Critical Minerals | 2025; Federal Register 90:50494-50497 | critical |
usgs2025
|
| European Union | Regulation (EU) 2024/1252, Annex II, Section 1(u), manganese | 2024 original act; OJ L 2024/1252, 3 May 2024 | critical |
eu2024
|
Microbial & Biochemical Mechanisms (1)
Mn(II) and complexed Mn(III) oxidation by Pseudomonas putida GB-1
redox transformation
Microbial
Associated Organisms:
Pseudomonas putida GB-1 (NCBITaxon:76869)
Growing GB-1 cultures converted defined soluble Mn substrates to filter-retained oxidized Mn. Mn(III)-citrate and Mn(III)-desferrioxamine B (DFOB) supported oxide accumulation, with lower and slower accumulation from the strongly complexed DFOB substrate.
Experimental Context & Analytical Limits:
Laboratory triplicates used 5 mL Minimal Media A with HEPES at pH 7.8, 30 degrees C, darkness, and 100 micromolar Mn supplied as MnCl2, Mn(III)-citrate, or Mn(III)-DFOB. Sterile medium and a GB-1 triple Mn-oxidase knockout were negative controls. Table 4 reports final GB-1 particulate oxide concentrations of 79.8 +/- 2.0 micromolar after 96 h from Mn(II), and 54.3 +/- 2.9 micromolar after 168 h from Mn(III)-DFOB. The table does not define the reported error statistic. These are LBB oxidizing equivalents calculated assuming particulate MnO2, not identification of a crystalline mineral or recovery of a purified product. No industrial extraction or recovery operation was tested.
Laboratory triplicates used 5 mL Minimal Media A with HEPES at pH 7.8, 30 degrees C, darkness, and 100 micromolar Mn supplied as MnCl2, Mn(III)-citrate, or Mn(III)-DFOB. Sterile medium and a GB-1 triple Mn-oxidase knockout were negative controls. Table 4 reports final GB-1 particulate oxide concentrations of 79.8 +/- 2.0 micromolar after 96 h from Mn(II), and 54.3 +/- 2.9 micromolar after 168 h from Mn(III)-DFOB. The table does not define the reported error statistic. These are LBB oxidizing equivalents calculated assuming particulate MnO2, not identification of a crystalline mineral or recovery of a purified product. No industrial extraction or recovery operation was tested.
Curated Evidence Points:
Support
Source:
wright2018
Culture conditions, Mn(III)-L oxidation methods, Fig. 1 and Table 4 support these assays. Mutants retaining MnxG or McoA oxidized Mn(III) complexes; this is genetic support, not purified-enzyme evidence.
Partial
Source:
wright2018
Fig. 3 and Discussion show abiotic Mn(III)-DFOB formation, so its accumulation alone is not proof of microbial oxidation. MopA activity was limited in darkness; the discussion reports stronger activity in light in separate KG_mopA cell-free-extract experiments. These findings limit universal enzyme and environmental extrapolation.
Sources & References
-
wright2018: Wright et al. (2018). Oxidative Formation and Removal of Complexed Mn(III) by Pseudomonas Species. Frontiers in Microbiology 9:560.
https://doi.org/10.3389/fmicb.2018.00560 (accessed 2026-10-09) -
chebi_manganese: ChEBI CHEBI:18291 - manganese atom
https://www.ebi.ac.uk/chebi/CHEBI:18291 (accessed 2026-10-09) -
ncbi_gb1: NCBI Taxonomy 76869 - Pseudomonas putida GB-1
https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=76869 (accessed 2026-10-09) -
usgs2025: USGS (2025). Final 2025 List of Critical Minerals. Federal Register 90:50494-50497, document 2025-19813.
https://www.govinfo.gov/content/pkg/FR-2025-11-07/html/2025-19813.htm (accessed 2026-10-09) -
eu2024: Regulation (EU) 2024/1252 of 11 April 2024. Original Official Journal text, 3 May 2024; Annex II, Section 1(u), manganese, page 57 of 67.
https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=OJ:L_202401252 (accessed 2026-10-09)
Curation History
| Timestamp | Curator | Action | Summary |
|---|---|---|---|
2026-10-09T04:47:22Z |
Codex (GPT-6; Codex) | record_creation | Curated the manganese element identity, USGS 2025 designation and scoped GB-1 laboratory oxidation evidence. Retained oxide-assay and abiotic/light limits; independent review remains a separate artifact. |
2026-10-09T05:51:49Z |
Codex (GPT-6; Codex) | criticality_extension | Added the historical EU 2024 Annex II designation through its named manganese entry, with source and mapping scope documented. Preserved existing scientific evidence; independent review is separate. |
Record source: data/records/manganese.yaml