Overview
Metabolomics is the comprehensive measurement of small-molecule metabolites (<1,500 Da) in a biological sample — the functional readout of what the genome, transcriptome, and microbiome are actually doing. While genomics tells you what organisms are present and metagenomics tells you what genes they carry, metabolomics reveals the metabolic products that directly affect the host.
In the WikiBiome context, metabolomics bridges two layers of evidence: it translates metal exposure and microbiome composition into measurable functional consequences. The integration of metallomics + metabolomics — measuring both metal speciation and metabolite profiles simultaneously — is a distinctive WikiBiome analytical approach.
Key Analytical Platforms
| Platform | Strengths | Common Use |
|---|---|---|
| LC-MS/MS (untargeted) | Broadest coverage; discovery mode | Serum, urine, fecal metabolomics |
| UHPLC-Q-TOF-MS | High mass accuracy for identification | Biomarker discovery |
| GC-MS | Best for volatile/semi-volatile metabolites | SCFA quantification |
| HILIC-UHPLC | Polar metabolite separation | Amino acids, nucleotides |
| NMR | Non-destructive; quantitative | Urine, serum profiling |
| ICP-MS | Metal speciation | Metallomic-metabolomic integration |
Metabolite Classes Relevant to WikiBiome
Short-Chain Fatty Acids ([[short-chain-fatty-acids]])
butyrate, propionate, acetate — the primary outputs of firmicutes fermentation. SCFA quantification by GC-MS is the most direct measure of beneficial microbiome metabolic activity. Depleted across inflammatory, neurodegenerative, and metabolic conditions.
Tryptophan Metabolites
The tryptophan metabolism pathway branches into serotonin, kynurenine, and indoles. Metabolomics reveals which branch dominates and whether inflammation (IDO1 induction) is diverting tryptophan from serotonin to neurotoxic kynurenine metabolites.
Bile Acids
Primary and secondary bile acid profiles reflect bile acid metabolism activity of gut bacteria. Deconjugation by BSH-producing organisms and 7-alpha-dehydroxylation are measurable metabolomic events.
Amino Acids
Branched-chain amino acids (BCAAs), aromatic amino acids, and their microbial derivatives (p-cresol, indoxyl sulfate, phenylacetylglutamine) serve as functional markers of dysbiosis.
Uremic Toxins
Indoxyl sulfate, p-cresyl sulfate, TMAO — microbially-derived metabolites that accumulate in chronic kidney disease and cardiovascular disease. Produced primarily by proteobacteria and specific firmicutes genera.
Metal-Metabolomics Integration
The most distinctive WikiBiome application: simultaneous measurement of metal speciation and metabolite profiles reveals how metal exposure reshapes microbial metabolism.
- Iron exposure produces the most distinct metabolomic signature in C. elegans — more disruptive than zinc or manganese [1].
- Heavy metal toxicity metabolomics reveals shared metabolic disruption patterns across Pb, Cd, Hg, As exposures (oxidative stress markers, amino acid depletion, energy metabolism disruption) [2].
- Metallomic-metabolomic COVID profiling in mother-infant dyads revealed coordinated metal-metabolite disruption during SARS-CoV-2 infection [3].
Disease Applications
| Condition | Key Metabolomic Findings |
|---|---|
| parkinsons disease | Serum metabolomics predicts motor progression; p-cresol elevated |
| autism spectrum disorder | Urinary tryptophan/purine metabolite disruption [4] |
| necrotizing enterocolitis | Formate as NEC-specific metabolic marker of enteric dysbiosis [5] |
| type 2 diabetes | Multi-omics (microbiome + metabolome) response to dietary fiber [6] |
| cerebral palsy | Amino acid metabolomics reveals reduced tryptophan pool [7] |
| multiple sclerosis | Pro-inflammatory metabolic signatures in Graves'/Hashimoto's/MS |
Cross-References
- microbiome derived metabolites — The metabolites metabolomics measures
- short chain fatty acids — Primary metabolomic target for microbiome health
- tryptophan metabolism — Key branching pathway revealed by metabolomics
- bile acid metabolism — Bile acid profiles as microbiome functional readout
- biomarkers — Metabolomic biomarker discovery
- iron — Iron exposure produces most distinct metabolomic signature
- dyshomeostasis — Metal-metabolite disruption patterns