Component
Human MMAA-MMUT complex
Human MMAA-MMUT complex
2 recorded relationships. Experimental role, claim status and evidence remain attached to each record.
How nutrients influence it
Every nutrient with a recorded effect on this component, credited to the nutrient that acted rather than the chapter that recorded it. Open a nutrient to see the findings and the conditions they were measured under.
Other things that act on it
Enzymes, hormones, genes, and other components with a recorded effect. These are not nutrients, so they do not count toward the arrows above. Each finding names the chapter that recorded it.
How nutrients reach it in more than one step
Chains of two or more recorded steps that end here, grouped by the nutrient they start from. Each step is a separate finding, so a chain is a route a mechanism could take, not proof that it does.
Tracing routes…
What it does
Every recorded relationship this component is part of, grouped by its role. Plain wording comes first; the technical statement follows.
Where it participates (unsigned role)
The human MMUT-MMAA structure showed MMAA stabilizing a roughly 180-degree rotation that exposed the MMUT B12-binding domain.
Experimental context and source evidence
- cross_nutrient
- false
- evidence_location
- Full text Results; Figures 2-4; cofactor off-loading and MMUT activity Methods
- experimental_model
- Purified human proteins
- exposure
- Crystallized complex with CoA, GDP and Mg2+
- limitations
- Static structure; does not directly measure the complete loading trajectory.
- nutrient_topic
- Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin B12 (cobalamins)
- organism
- Homo sapiens
- plain_language
- The human-protein structure showed how MMAA opens access to MMUT-bound B12.
- primary_references
- [mascarenhas-2023-nanoassembly] Architecture of the human G-protein-methylmalonyl-CoA mutase nanoassembly for B12 delivery and repair. (2023). https://pubmed.ncbi.nlm.nih.gov/37468522/ DOI: 10.1038/s41467-023-40077-4
- tissue_or_cell_type
- Purified protein assay
Vitamin B12: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1117–1129
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Purified human proteins · source_derived_draft · unverified_draft
### mmaa-exposes-mmut-cobalamin-domain The human MMUT-MMAA structure showed MMAA stabilizing a roughly 180-degree rotation that exposed the MMUT B12-binding domain. Condition category: normal nutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. plain_language: The human-protein structure showed how MMAA opens access to MMUT-bound B12. organism: Homo sapiens tissue_or_cell_type: Purified protein assay experimental_model: Purified human proteins limitations: Static structure; does not directly measure the complete loading trajectory. exposure: Crystallized complex with CoA, GDP and Mg2+ cross_nutrient: false evidence_location: Full text Results; Figures 2-4; cofactor off-loading and MMUT activity Methods [mascarenhas-2023-nanoassembly] Architecture of the human G-protein-methylmalonyl-CoA mutase nanoassembly for B12 delivery and repair. (2023). https://pubmed.ncbi.nlm.nih.gov/37468522/ DOI: 10.1038/s41467-023-40077-4
Complete structured claim and evidenceHuman MMAA formed a stable complex preferentially with apo-MMUT and with GMPPNP rather than GDP.
Experimental context and source evidence
- cross_nutrient
- false
- evidence_location
- Indexed primary abstract; indexed Results
- experimental_model
- Purified human proteins
- exposure
- Apo versus holo-MMUT; GMPPNP versus GDP
- limitations
- GMPPNP is a GTP analogue; stable-complex abundance is not cofactor transfer rate.
- nutrient_topic
- Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. · Vitamin B12 (cobalamins)
- organism
- Homo sapiens
- plain_language
- The purified human proteins assembled differently depending on MMUT cofactor occupancy and nucleotide state.
- primary_references
- [froese-2010-human-mmaa] Structures of the human GTPase MMAA and vitamin B12-dependent methylmalonyl-CoA mutase and insight into their complex formation. (2010). https://pubmed.ncbi.nlm.nih.gov/20876572/ DOI: 10.1074/jbc.m110.177717
- tissue_or_cell_type
- Purified protein assay
Vitamin B12: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1047–1059
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Purified human proteins · source_derived_draft · unverified_draft
### mmaa-prefers-apo-mmut-complex Human MMAA formed a stable complex preferentially with apo-MMUT and with GMPPNP rather than GDP. Condition category: normal nutrient_topic: Vitamin B12 research collection; topical membership is not evidence of a direct dietary effect. plain_language: The purified human proteins assembled differently depending on MMUT cofactor occupancy and nucleotide state. organism: Homo sapiens tissue_or_cell_type: Purified protein assay experimental_model: Purified human proteins limitations: GMPPNP is a GTP analogue; stable-complex abundance is not cofactor transfer rate. exposure: Apo versus holo-MMUT; GMPPNP versus GDP cross_nutrient: false evidence_location: Indexed primary abstract; indexed Results [froese-2010-human-mmaa] Structures of the human GTPase MMAA and vitamin B12-dependent methylmalonyl-CoA mutase and insight into their complex formation. (2010). https://pubmed.ncbi.nlm.nih.gov/20876572/ DOI: 10.1074/jbc.m110.177717
Complete structured claim and evidence
The events it takes part in
A mechanism often involves more than two components. These are the full events, with every participant and its role.
Situations it appears in
Low-supply and faulty-machinery situations recorded in the chapters where this component plays a part.
In the sources
Preserved passages that mention this component, quoted exactly. Open one to read it in context.
Open hypotheses
Proposed ideas that involve this component. They are labeled as hypotheses and do not change any recorded statement.
This is a research prototype built from draft material. It is not medical advice, and its statements still await verification against the original studies.