Microbial Melanin Biosynthesis and Applications

Melanin is a heterogeneous biopolymer produced by bacteria, fungi and yeasts via enzyme-catalysed oxidation and polymerisation of phenolic or indolic substrates. Two principal enzyme families, tyrosinases and laccases, initiate the conversion of L-tyrosine or dihydroxynaphthalene precursors into monomeric intermediates that undergo radical coupling to yield eumelanin, pheomelanin or pyomelanin. Microbial pathways often assemble in operons, enabling coordinated regulation and efficient pigment formation under stress conditions. Beyond classical roles in photoprotection and radical scavenging, microbial melanin has been harnessed for diverse applications. Biocompatible and biodegradable, these pigments serve as antioxidants, anticancer and antimicrobial agents, radioprotectants and UV filters in pharmaceuticals and cosmetics. Their conductive and semiconductive properties underpin uses in organic electronics and bioelectronics, while metal-binding capacity supports environmental bioremediation. Advances in fermentation and metabolic engineering now enable sustainable production of tailored melanin polymers at industrial scale.

Research from Nature Portfolio

Optimisation of melanin yield and bioactivity has been demonstrated in a soil-derived actinobacterial strain, where statistical designs refined medium composition and culturing parameters to elevate extracellular pigment production. The purified melanin exhibited characteristic spectral features and nanoscale particle morphology, displaying potent antioxidant and anticancer activities against melanoma cells at low micromolar concentrations. In parallel, a marine-derived bacterial platform was developed to generate nanometre-sized melanin particles. These nanomelanin spheres were incorporated into a polyhydroxybutyrate matrix to form a flexible, thermostable nanocomposite film. The composite combined antimicrobial efficacy against multidrug-resistant pathogens with strong radical-scavenging properties, suggesting applications in active food packaging and protective biomedical coatings.

Microbial Melanin Biosynthesis and Applications publication trend

The graph below shows the total number of articles in microbial melanin biosynthesis and applications across all publications each year (not limited to Nature Index journals).

Technical terms

Tyrosinase: An oxidoreductase enzyme that catalyses the conversion of phenolic substrates, such as L-tyrosine, to quinones initiating melanin polymerisation.

Laccase: A multicopper oxidase that oxidises a broad range of phenolic and non-phenolic substrates, contributing to melanin biosynthesis and cross-linking.

Response Surface Methodology (RSM): A statistical technique for modelling and optimisation of complex processes by evaluating interactions between multiple variables.

Pyomelanin: A nitrogen-free melanin synthesised via the homogentisic acid pathway, characterised by its polymeric structure and high metal-binding capacity.

Nanocomposite: A composite material incorporating nanoscale particles, combining distinct functional properties such as mechanical strength, conductivity and antimicrobial activity.

References

1. Bioproduction and optimization of newly characterized melanin pigment from Streptomyces djakartensis NSS-3 with its anticancer, antimicrobial, and radioprotective properties. Microbial Cell Factories (2024).
2. Microbial production of melanin and its various applications. World Journal of Microbiology and Biotechnology (2020).
3. Synthesis of Nm-PHB (nanomelanin-polyhydroxy butyrate) nanocomposite film and its protective effect against biofilm-forming multi drug resistant Staphylococcus aureus. Scientific Reports (2017).
4. Production of Melanins With Recombinant Microorganisms. Frontiers in Bioengineering and Biotechnology (2019).