BRS5-FM3-PM8 - Neurotransmitter Precursor Biotransformation & Availability
1. Definition
Microbial and absorptive processes that influence availability of central neurotransmitter precursors such as tryptophan and tyrosine.
This PM captures the gut-side contribution to precursor availability within BRS5(FM3) - Gut-Vagal Neuromodulation & ENS Signalling, without redefining the core neurotransmitter biology already housed in BRS1 [1][2].
2. Functional Role
↑ tryptophan/tyrosine availability for central synthesis
3. Target Functional Outcome / Phenome
These mappings are translational relationships, not single-mechanism outcome claims. Phenomes are emergent functional patterns supported by multiple interacting PMs across the BRAIN Framework.
No direct functional outcome relationship currently mapped.
4. Levers
Intervention Profile
Intervention Dominance: Diet-Supported
4.1 Dietary Levers
4.1.1 Direct Dietary Levers
- Protein-rich whole foods ← precursor supply context
- Fibre/polyphenol-rich pattern ← absorptive and ecological support
- Lower-dysbiosis pattern ← improved precursor-handling environment
4.1.2 Cofactors and Supporting Inputs
- B6
- iron
- magnesium
- protein sufficiency
4.1.3 KCs (Key Constraints)
4.2 Lifestyle Levers
- Repeated dietary pattern quality matters more than isolated amino-acid emphasis.
- Sleep, stress, and meal irregularity may indirectly worsen gut-side precursor context.
5. Mechanistic Basis
Summary
BRS5-FM3-PM8 links microbial ecology, barrier integrity, and dietary precursor context to the availability of neurotransmitter-relevant amino acids for downstream BRS1 use [1][2].
Gut-side precursor handling and neurotransmitter relevance
(Gut influence on precursor availability)
Gut ecology and barrier state can influence precursor metabolism, absorptive context, and the downstream availability of amino acids relevant to central neurotransmitter synthesis.
(Not a replacement for BRS1)
This PM does not move neurotransmitter synthesis into BRS5; it describes how the gut environment can influence the precursor context that BRS1 mechanisms later use.
(Pattern-level support)
Protein-rich whole foods, fibre/polyphenol-supported ecology, and lower dysbiosis burden are more relevant than any single “precursor food” in isolation.
6. BRS Pathways and Connections
6.1 BRS Pathways
- None listed
6.2 Connected BRS Mechanisms
- None listed
6.3 Connected Primary Mechanisms
7. Scoreable Inputs & Modulation Signals
This PM is scoreable through precursor-support and gut-context signals.
Scoreable Input Categories
| Input Category | Example Inputs | PM6 Relevance |
|---|---|---|
| Functional Property Potentials | precursor_support; gut_barrier_support; lower_dysbiosis_context | May support precursor biotransformation and availability. |
| Realised Functional States | protein_plus_fibre_pattern; lower_dysbiosis_pattern | Reflect practical gut-side precursor support states. |
| Preparation Transformations | minimally_processed; whole_food_matrix | May preserve precursor and absorptive context. |