Component
PDH E1 phosphorylated at alpha Ser264
Human E1 with phosphorylation at site 1 in mature-chain numbering; experimental S1 construct has the other two phosphorylation sites replaced.
1 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.
What it acts on
Phosphorylated human site-1-only E1 lacked detectable lipoylated-L2 binding and reductive acetylation, despite high ThDP in the binding assay.
Experimental context and source evidence
- evidence
- [{"paper_key": "kato-2008-pdh-phosphorylation", "source_bundle": "artifacts/thiamine_metabolism_sources.json", "passage_ids": ["p-51"], "locator": "absence of L2 binding", "preservation": "Exact text retained in the source bundle; full source document retained when openly retrievable."}]
- experimental_model
- Engineered human site-1-only E1; phosphorylation, ITC and kinetics.
- limitations
- Normal regulatory phosphorylation studied in an engineered construct; not a dietary deficiency or clinical nonresponse experiment.
- nutrient
- Thiamine (vitamin B1) · Thiamine (vitamin B1)
- nutrient_topic
- Thiamine research collection; topical membership is not evidence of a direct dietary effect. · Thiamine (vitamin B1)
- organism
- Homo sapiens
- plain_language
- Loading B1 cannot by itself undo this tested regulatory block: the phosphorylated enzyme fails to engage its lipoyl partner.
- primary_references
- [kato-2008-pdh-phosphorylation] Structural basis for inactivation of the human pyruvate dehydrogenase complex by phosphorylation: role of disordered phosphorylation loops (2008). https://pubmed.ncbi.nlm.nih.gov/19081061/ DOI: 10.1016/j.str.2008.10.010
- tissue_or_cell_type
- Purified proteins
Thiamine: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 704–715
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Engineered human site-1-only E1; phosphorylation, ITC and kinetics. · source_derived_draft · unverified_draft
### b1-pdh-phosphorylation-blocks-lipoyl-recognition Phosphorylated human site-1-only E1 lacked detectable lipoylated-L2 binding and reductive acetylation, despite high ThDP in the binding assay. Condition category: normal nutrient_topic: Thiamine research collection; topical membership is not evidence of a direct dietary effect. plain_language: Loading B1 cannot by itself undo this tested regulatory block: the phosphorylated enzyme fails to engage its lipoyl partner. organism: Homo sapiens tissue_or_cell_type: Purified proteins experimental_model: Engineered human site-1-only E1; phosphorylation, ITC and kinetics. limitations: Normal regulatory phosphorylation studied in an engineered construct; not a dietary deficiency or clinical nonresponse experiment. evidence: [{"paper_key": "kato-2008-pdh-phosphorylation", "source_bundle": "artifacts/thiamine_metabolism_sources.json", "passage_ids": ["p-51"], "locator": "absence of L2 binding", "preservation": "Exact text retained in the source bundle; full source document retained when openly retrievable."}] nutrient: Thiamine (vitamin B1) [kato-2008-pdh-phosphorylation] Structural basis for inactivation of the human pyruvate dehydrogenase complex by phosphorylation: role of disordered phosphorylation loops (2008). https://pubmed.ncbi.nlm.nih.gov/19081061/ DOI: 10.1016/j.str.2008.10.010
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.