Microbe that reproduces by bursting open could boost omega-3 production – study

A microbe that reproduces in a way reminiscent of the horror film Alien could help boost production of omega-3 oils, researchers have said.

The microscopic creature, named Caledochytrium aldermaii, reproduces by growing one or more cells inside its own body before bursting to release them, in a process never before seen in organisms of its type.

The “peculiar” reproductive process was discovered by a team that includes scientists from two Scottish universities, who reported their disbelief when they caught it on camera.

But unlike Ridley Scott’s deadly xenomorph, the tiny lifeform is completely harmless to humans.

Instead the researchers said it could help improve the production of valuable omega-3 oils and provide a natural source of the pink food colours called carotenoids.

Both are used in food supplements, infant formula and animal and fish farming. The cells are also approximately 50% protein.

Professor Peter Morris, a plant biologist at Heriot-Watt University’s School of Energy Geoscience, Infrastructure and Society, said: “Instead of dividing into two, as we would expect, the mature cells develop a large internal chamber in which entirely new daughter cells grow.

“Some of those daughters already have another developing generation inside them, before they are released when the mother cell breaks open.

“Understanding how this species reproduces is key to understanding how it could be used in commercial settings, like aquaculture.”

The microbe belongs to a little-known group of marine microorganisms called Labyrinthulomycetes, which act as some of nature’s recyclers by breaking down dead organic matter in seas and other salty waters.

Dr Jane Polglase has studied the organisms for almost 50 years, and founded a company called Strameno – a “spin-out” from Heriot-Watt University – to explore their commercial potential.

Scientists have become increasingly interested in Labyrinthulomycetes because they naturally produce high levels of healthy omega-3 fatty acids – including DHA, the same nutrient found in oily fish.

Dr Polglase said: “We’ve been investigating this particular group of microbes for decades, because of their products and role in the environment, but when we captured the reproduction, using an electron microscope, we couldn’t believe what we were seeing.

“While lots of scientists now focus on the DNA of any creature, we’ve taken an old-fashioned approach, also observing the microbe’s behaviour and describing its morphology fully.

“If we had not done that, we never would have captured this peculiar reproductive process on camera.”

She said the marine environment “swarms with microbes” about which very little is generally known.

“In this case, we have found Caledochytrium in association with Scottish octopuses and their lairs, with rainbow trout and on their own in the middle of a salt marsh on Scotland’s east coast,” Dr Polglase explained.

“We now know they’re doing essential work, returning animal and plant remains to the environment.

“But they have really unusual behaviours, like their method of reproduction and the unique membrane network they use for movement, feeding and buoyancy.”

She said the “useful compounds” that Caledochytrium and other Labyrinthulomycetes make for their own growth and reproduction are also used by other organisms, not just humans.

“Even the network of membranes, which they spin out, is left behind on any surface when they move on,” Dr Polglase went on.

“Marine larvae are attracted to feast on these, moving the protein and lipids up the food chain when they are eaten by grazing organisms.

“Knowing how these ecosystems work is vital for keeping them healthy.”

She added: “Even in 2026 we are finding forms of life with behaviours and biology we have never seen before; it’s a fascinating field of research.”

The discovery was reported in the academic journal Protist by a long-standing consortium of scientists from Heriot-Watt University, the HWU spinout company Strameno, the Centre for Environment, Fisheries and Aquaculture Science (CEFAS) Weymouth and the Institute of Aquaculture at Stirling University.