Component
Thioredoxin proteins
Thioredoxin substrate family for records where source access does not establish the assay-substrate species; do not infer human TXN1.
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 acts on it
Replacing rat TXNRD1 Sec498 with cysteine lowered thioredoxin-reduction kcat about 100-fold; serine substitution and terminal truncation lacked detectable activity.
Experimental context and source evidence
- availability_state
- machinery_impairment Imported condition classification; unverified.
- cross_nutrient
- B2-derived FAD cannot replace the selenium-containing catalytic residue.
- evidence_location
- Abstract
- experimental_model
- Rat TXNRD1 Sec498Cys, Sec498Ser and C-terminal truncation expressed in E. coli; FAD analysis, NADPH titration and thioredoxin assays.
- exposure
- Purified-enzyme assay
- limitations
- Assay-substrate species is unresolved in accessible source details; engineered proteins do not establish dietary B2-by-selenium synergy.
- nutrient_topic
- Riboflavin research collection; topical membership is not evidence of a direct dietary effect. · Riboflavin (vitamin B2)
- organism
- Rattus norvegicus protein expressed in Escherichia coli
- plain_language
- Flavin retention did not preserve efficient thioredoxin reduction.
- primary_references
- [zhong2000] Essential role of selenium in the catalytic activities of mammalian thioredoxin reductase revealed by characterization of recombinant enzymes with selenocysteine mutations. (2000). https://pubmed.ncbi.nlm.nih.gov/10849437/ DOI: 10.1074/jbc.m000690200
- tissue_or_cell_type
- Purified recombinant enzyme; no intact tissue
- trigger_kind
- machinery_impairment Imported condition classification; unverified.
Riboflavin: mechanisms, deficiency and nutrient interactions (2026-09-17) · lines 1388–1400
AI-assisted literature curation; primary study URLs and scope retained in the document and extraction. Not publisher full text. · supports · Rat TXNRD1 Sec498Cys, Sec498Ser and C-terminal truncation expressed in E. coli; FAD analysis, NADPH titration and thioredoxin assays. · source_derived_draft · unverified_draft
### b2-txnrd-sec498cys-turnover Replacing rat TXNRD1 Sec498 with cysteine lowered thioredoxin-reduction kcat about 100-fold; serine substitution and terminal truncation lacked detectable activity. Condition category: machinery_impairment nutrient_topic: Riboflavin research collection; topical membership is not evidence of a direct dietary effect. plain_language: Flavin retention did not preserve efficient thioredoxin reduction. organism: Rattus norvegicus protein expressed in Escherichia coli tissue_or_cell_type: Purified recombinant enzyme; no intact tissue experimental_model: Rat TXNRD1 Sec498Cys, Sec498Ser and C-terminal truncation expressed in E. coli; FAD analysis, NADPH titration and thioredoxin assays. limitations: Assay-substrate species is unresolved in accessible source details; engineered proteins do not establish dietary B2-by-selenium synergy. exposure: Purified-enzyme assay cross_nutrient: B2-derived FAD cannot replace the selenium-containing catalytic residue. evidence_location: Abstract [zhong2000] Essential role of selenium in the catalytic activities of mammalian thioredoxin reductase revealed by characterization of recombinant enzymes with selenocysteine mutations. (2000). https://pubmed.ncbi.nlm.nih.gov/10849437/ DOI: 10.1074/jbc.m000690200
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.