Scientists at UC San Diego have successfully used bacteria to reproduce a unique pigment that allows octopuses to blend in with their surroundings, according to newly published research.
In nature, octopuses can blend in with coral reefs and other features in their environment, as well as flash warning stripes in seconds, thanks to a pigment known as xanthommatin.
Now, achieving yields much higher than in earlier attempts, the team behind the study recently published in Nature Biotechnology marks a significant advance in biomimetic chemistry and bioengineering. The team believes their research could lead to real-world applications ranging from color-changing paint to natural sunscreen, and other potentially new technologies.
A Natural Master of Disguise
Octopus, squid, cuttlefish, and other cephalopods can rapidly change color as part of their natural camouflage ability. Specialized cells under their skin contain natural pigments that expand or contract, allowing these animals to shift their appearance in seconds. Xanthommatin is one of the main pigments responsible for the orange, red, and brown colors seen in these animals.
Monarch butterflies and dragonflies also contain xanthommatin in their colorful wings and bodies. While it is common in nature, recreating the pigment in the lab has been challenging. Traditional chemical methods yield only a few milligrams per liter, limiting research into the pigment’s structure and possible uses.
Engineering the Camouflage
The UC San Diego team, led by marine chemist Bradley Moore at Scripps Institution of Oceanography, took a biological approach to reproduce this pigment. Working with the Novo Nordisk Foundation Center for Biosustainability in Denmark, they engineered bacteria to produce xanthommatin through a technique known as growth-coupled biosynthesis.
Rather than adding a new compound to the bacteria, the researchers made the bacteria’s survival dependent on producing xanthommatin. The researchers started with a specially engineered bacterial strain that required both xanthommatin and formic acid to grow. Each time the bacteria produced a pigment molecule, it also produced formic acid as a by-product. This additional compound played a role in fueling the cell’s metabolism and maintaining its function.
“We made it such that activity through this pathway, of making the compound of interest, is absolutely essential for life,” said Leah Bushin, the study’s lead author and faculty member at Stanford University. “If the organism doesn’t make xanthommatin, it won’t grow.”
Rapid Scaling Breakthrough
Co-author Adam Feist and his team then utilized automated systems to tweak and optimize microbial genomes over hundreds of generations. Within a few days, the bacteria produced between one and three grams of pigment per liter, up to 1,000 times more than in traditional methods.
“It was one of my best days in the lab,” Bushin recalled. “When I came in the next morning and realized it worked and it was producing a lot of pigment, I was thrilled. Moments like that are why I do science.”
This breakthrough now makes xanthommatin much more accessible for future research and technological applications.
Color-Changing Futures
The unique properties of xanthommatin could have applications in many areas through the practice of biomimicry. Since it responds to light, the pigment could be used in photoelectronic devices by enabling dynamic colors or displays. The potential uses for this technology range from adaptive camouflage for the military to eco-friendly dyes for more sustainable textiles. Defense researchers are interested in its potential for natural stealth, while cosmetic companies are evaluating its UV-absorbing properties for sunscreens that may better protect skin against sunlight.
“This project gives a glimpse into a future where biology enables the sustainable production of valuable compounds and materials through advanced automation, data integration, and computationally driven design,” said Feist.
Moore agrees. “We’ve really disrupted the way that people think about how you engineer a cell,” he said. “This new method solves a supply challenge and could now make this biomaterial much more broadly available.”
Rethinking Biomanufacturing
The study alludes to a possible shift in how materials are manufactured. Rather than relying on petrochemicals, biomanufacturing could use natural systems to produce sustainable materials from molecules.
“As we look to the future, humans will want to rethink how we make materials to support our synthetic lifestyle of eight billion people on Earth,” said Moore. “Thanks to federal funding, we’ve unlocked a promising new pathway for designing nature-inspired materials that are better for people and the planet.”
Austin Burgess is a writer and researcher with a background in sales, marketing, and data analytics. He holds a Master of Business Administration and a Bachelor of Science in Business Administration, along with a certification in Data Analytics. His work combines analytical training with a focus on emerging science, aerospace, and astronomical research.