Overview
- pH
- 1.7
- Notes
- Nitrogen-free medium developed for selective isolation of Leptospirillum ferrodiazotrophum (Leptospirillum group III), the nitrogen-fixing member of Richmond Mine biofilm. Richmond Mine AMD biofilm sample naturally abundant in group III was homogenized, filtered, and serially diluted into nitrogen-free liquid medium. Culture grew autotrophically to maximum density ~10^6 cells/ml, oxidizing ferrous iron as sole energy source. Ammonium sulfate deliberately omitted to select for diazotrophic organisms capable of nitrogen fixation. This selective isolation strategy was guided by metagenomic data showing a single nif operon on a Leptospirillum group III genome fragment. Axenic culture confirmed by 16S rRNA-ITS clone library analysis. Note: This medium supports L. ferrodiazotrophum but not the complete biofilm community.
Composition
flowchart LR
CultureMech_015436["nitrogen_free_medium_for_leptospirillum_ferrodiazotrophum"]
ing0_Iron_II__sulfate["Iron(II) sulfate"]
CultureMech_015436 --> ing0_Iron_II__sulfate
CHEBI_75832["CHEBI:75832"]
ing0_Iron_II__sulfate -.-> CHEBI_75832
ing1_Magnesium_sulfate["Magnesium sulfate"]
CultureMech_015436 --> ing1_Magnesium_sulfate
CHEBI_32599["CHEBI:32599"]
ing1_Magnesium_sulfate -.-> CHEBI_32599
ing2_Monopotassium_phosphate["Monopotassium phosphate"]
CultureMech_015436 --> ing2_Monopotassium_phosphate
CHEBI_63036["CHEBI:63036"]
ing2_Monopotassium_phosphate -.-> CHEBI_63036
Ingredients (3)
| # | Ingredient | Concentration | Ontology | Notes |
|---|---|---|---|---|
| 1 |
Iron(II) sulfate
Fe.O4S 151.908 g/mol
|
30.0 G_PER_L |
CHEBI:75832
iron(2+) sulfate (anhydrous)
|
|
| 2 |
Magnesium sulfate
Mg.O4S 120.368 g/mol
|
0.4 G_PER_L |
CHEBI:32599
magnesium sulfate
|
|
| 3 |
Monopotassium phosphate
H2O4P.K 136.084 g/mol
|
0.05 G_PER_L |
CHEBI:63036
potassium dihydrogen phosphate
|
Target organisms
No target organisms are recorded.
Provenance
Merged from 1 source record.
- Nitrogen_Free_Medium_for_Leptospirillum_ferrodiazotrophum (CultureMech:015436)
| Timestamp | Curator | Action | Notes |
|---|---|---|---|
| 2026-03-15T00:15:00.445462Z | communitymech-importer-v1.0 | Imported from CommunityMech | Created from CommunityMech:000059 growth_media record |
| 2026-03-17T06:30:00.000000Z | mediaingredientmech-enrichment-v1.0 | Added MediaIngredientMech links | Linked ingredients to MediaIngredientMech identifiers |
| 2026-03-17T19:46:07.624740+00:00 | normalize_media_names_to_snake_case.py | NAME_NORMALIZED | Normalized name from "Nitrogen-Free Medium for Leptospirillum ferrodiazotrophum" to "nitrogen_free_medium_for_leptospirillum_ferrodiazotrophum" for consistent matching |
| 2026-05-24T04:38:33.284210+00:00 | backfill_source_environment.py | BACKFILLED_SOURCE_ENVIRONMENT | added=1 env(s) from CommunityMech |
| 2026-06-05T07:40:29.560526+00:00 | mim-legacy-to-chebi-migration-v1.0 | Refreshed legacy MediaIngredientMech links to CHEBI keying | Replaced 2 legacy mediaingredientmech_term link(s) with mediaingredientmech_chebi_term (id-safe: ingredient's own CHEBI + label). MIM deprecated the MediaIngredientMech:NNNNNN id scheme. |
| 2026-08-06T03:05:04.716236+00:00 | merge_recipes.py | MERGED_RECIPES | merged 1 source recipe(s) on fingerprint ffbc81727eec505f702ca059ecaf9d44be70ec4635f6be877f545ed01dffe9d8 |