In the world of microscopic organisms, cyanobacteria are master chemists, brewing compounds that could revolutionize medicine.
Cyanobacteria are among the oldest living organisms on Earth, with fossils dating back an astonishing 3.5 billion years 3 . These photosynthetic bacteria are credited with creating our oxygen-rich atmosphere, paving the way for complex life to evolve 2 .
What makes cyanobacteria particularly fascinating to scientists today is their remarkable ability to produce a diverse array of bioactive secondary metabolites 2 .
With antibiotic resistance rising and cancer treatments often needing refinement, researchers are turning to cyanobacteria as a source of novel therapeutic compounds 3 .
Novel therapeutic compounds
New weapons against superbugs
Complex chemical production
Sustainable production methods
| Metabolite Class | Key Examples | Biological Activities | Producing Genera |
|---|---|---|---|
| Non-ribosomal peptides | Microcystin, Cyanopeptolin | Protease inhibition, Hepatotoxicity | Microcystis, Planktothrix 2 |
| Polyketides | Curacin A, Jamaicamide | Cytotoxic, Anticancer | Moorea, Lyngbya 2 8 |
| Alkaloids | Anatoxin-a, Saxitoxin | Neurotoxicity | Anabaena, Aphanizomenon 2 6 |
| Ribosomally synthesized and post-translationally modified peptides (RiPPs) | Patellamide, Microviridin | Protease inhibition, Cytotoxicity | Prochloron, Microcystis 2 6 |
| Isoprenoids/Terpenoids | β-carotene, Geosmin | Antioxidant, Pigmentation | Various 2 |
The most abundant class of cyanobacterial metabolites are peptides, which account for approximately 61.5% of newly discovered compounds 9 .
These include non-ribosomal peptides (NRPs) synthesized by large enzyme complexes without ribosomal instruction, and ribosomally synthesized and post-translationally modified peptides (RiPPs) that start as ribosomal products before undergoing extensive chemical modification 2 .
Alkaloids, nitrogen-containing compounds, represent another significant class with potent biological activities. These include neurotoxins like anatoxin-a and saxitoxin, which can be harmful in environmental blooms but may have therapeutic applications in controlled doses 2 6 .
Terpenoids (or isoprenoids) include familiar compounds like β-carotene, known for its antioxidant properties, and geosmin, which gives soil its characteristic earthy smell after rain 2 .
Perhaps the most promising application of cyanobacterial compounds is in cancer treatment. Numerous metabolites have demonstrated potent cytotoxicity against various cancer cell lines 3 .
With antibiotic resistance emerging as a global health crisis, cyanobacterial metabolites offer new hope. Many compounds exhibit activity against drug-resistant bacteria 3 .
Discovery of Dolastatin 10 from marine cyanobacterium Moorea producens 8
Development of synthetic analogs based on cyanobacterial compounds
FDA approval of Brentuximab vedotin (Adcetris®) for Hodgkin lymphoma 8
Expanded research into cyanobacterial compounds for antibiotic-resistant infections 3
A groundbreaking study published in 2025 explored cyanobacteria from the Cape Verde Archipelago as potential sources of nitric oxide (NO) donors with applications in dermatology and cosmetics 1 .
| Strain | Antioxidant Activity (IC50) | LOX Inhibition (IC25) | NO Donor Ability | Potential Application |
|---|---|---|---|---|
| Salileptolyngbya sp. LEGE 181184 | 46.50 μg mL−¹ (superoxide anion) | Not specified | Yes (from 12.5 μg mL−¹) | Dermatology, Cosmetics 1 |
| Salileptolyngbya sp. LEGE 181150 | Not specified | 28.49 μg mL−¹ | Yes (from 12.5 μg mL−¹) | Anti-inflammatory formulations 1 |
| All studied strains | Varied antioxidant potential | Varied inhibition | Yes (all strains) | Natural antimicrobial ingredients 1 |
This pioneering study highlights cyanobacteria aqueous extracts as innovative, bio-based natural ingredients that, through NO-donating mechanisms, could potentially combat antibiotic-resistant strains, making them valuable candidates for dermatological therapies 1 .
| Research Tool | Function | Examples/Applications |
|---|---|---|
| antiSMASH | Identifies biosynthetic gene clusters (BGCs) in cyanobacterial genomes | Predicts potential metabolite production; 33 different BGC types identified in 196 cyanobacteria genomes 6 |
| HPLC-NMR-MS | Hyphenated analytical technique for compound separation and structural elucidation | Enables identification of novel compounds produced in scarce amounts 8 |
| Genome Sequencing | Reveals genetic potential for metabolite production | CyanoGEBA project sequencing cyanobacteria genomes to identify BGCs 8 |
| Metabolic Engineering | Enhances production of valuable compounds through genetic modification | 83% enhancement in ethanol production after engineering pyruvate carboxylase in Synechocystis sp. PCC 6803 8 |
| Marfey's Method | Determines absolute configuration of amino acids in peptides | Used to establish stereochemistry in cyclic depsipeptides like urumamide and medusamide A 8 |
Search for cyanobacterial metabolites in unique ecological niches with unusual bioactivities 7 .
The future of cyanobacterial research is bright, with several emerging trends pointing toward expanded applications.
Synthetic biology approaches are being increasingly applied to engineer cyanobacterial strains for enhanced production of valuable metabolites 4 6 .
The vision of developing a "green E. coli"—a cyanobacterial chassis strain that can be easily manipulated with standardized genetic parts—is driving innovation in the field 4 .
Genome mining techniques are allowing researchers to identify biosynthetic gene clusters for novel compounds without the need for traditional activity-guided isolation 5 8 .
This approach has revealed that cyanobacteria possess far greater chemical potential than previously recognized, with many silent gene clusters awaiting activation under the right conditions.
The search for cyanobacterial metabolites has also expanded to extreme environments, based on the understanding that unique ecological niches often select for novel chemical structures with unusual bioactivities 7 .
Cyanobacteria from thermal springs, hypersaline lakes, polar regions, and other challenging habitats are increasingly targeted for drug discovery initiatives.
Thermal Springs
Hypersaline Lakes
Polar Regions
Geothermal Areas
In conclusion, cyanobacteria represent a remarkable and still underexplored resource for pharmaceutical development.
Their billions of years of evolutionary history have equipped them with sophisticated biochemical pathways to produce compounds with precisely the kinds of bioactivities needed in modern medicine.
As research continues to unravel the mysteries of these ancient chemical factories, we can anticipate a new era of therapeutic agents inspired by some of Earth's oldest inhabitants.