- Bioactive peptides are mapped by mode of action, not by source.
- Core classes: antimicrobial, antihypertensive, antioxidant, antithrombotic, immunomodulatory, opioid, mineral-binding.
- Function is driven by sequence, composition, and 3D conformation.
- Multifunctionality is the rule, not the exception — classes overlap.
If you want to reason about a peptide quickly, classify it by what it does. Here's the functional map and what governs it.
The functional classes
The standard taxonomy sorts bioactive peptides by mode of action: antimicrobial, anti-thrombotic, antihypertensive, opioid, immunomodulatory, mineral-binding, and antioxidative (Food Quality and Safety review). Antimicrobial peptides subdivide further into antibacterial, antifungal, and antiviral types, often acting by disrupting microbial membranes (Bioactive peptides review).
What determines the class
Activity is a function of structure. The behavior of these peptides depends on amino acid composition, three-dimensional conformation, charge, and hydrophobicity (Bioactive peptides review). Change the sequence, and you can change the function — which is the entire basis of designing peptides for a target.
| Class | Action | Note |
|---|---|---|
| Antihypertensive | Lowers blood pressure | Often ACE-inhibitory |
| Antimicrobial | Disrupts microbial membranes | Anti-bacterial/fungal/viral |
| Antioxidant | Neutralizes oxidative stress | Common in food peptides |
| Immunomodulatory | Adjusts immune response | Broad activity |
| Opioid | Binds opioid receptors | E.g., from milk proteins |
Multifunctionality
Don't expect clean boundaries. A peptide can be antihypertensive and simultaneously carry other activities (Food Quality and Safety review) — classifiers in research increasingly screen for multiple functions at once because single-function assumptions miss real behavior.
Key takeaways
- Classify by mode of action for fast reasoning.
- Sequence, charge, conformation, and hydrophobicity drive function.
- Antimicrobial peptides act largely via membrane disruption.
- Assume multifunctionality until proven otherwise.