MATT DAMON’S character in The Martian has to grow potatoes in his own faeces to survive on Mars. But there may be more appealing ways to make food in space, like using bacteria to make chemicals we can eat, such as sugar.

“The first pilgrims who came to the Americas didn’t bring all their food for the rest of their lives,” says Lynn Rothschild of NASA’s Ames Research Center. “You need to live off the land.”

“The first pilgrims didn’t bring all their food for the rest of their lives. You have to live off the land”


The idea is now set to be put to the test in space for the first time. Genetically modified bacteria will be sent up on a German satellite in 2017 to see if they can survive the launch and cosmic radiation, and function under reduced gravity.

The satellite will spin for six months at a speed that simulates Martian gravity, which is one-third that on Earth. It will also test the same bacteria under lunar and zero gravity, to see if they could function on the moon or a space station.

The sugar could be turned into not only food, but also fuel. And bacteria could also be engineered to make drugs and building materials (see “Bacterial origami“), slashing a spacecraft’s payload. “Launching things against Earth gravity is extremely expensive. This is the obvious way to break through the problem of ‘upmass’,” Rothschild says.

The linchpin is a type of plankton called Anabaena, which uses photosynthesis to make sugars from carbon dioxide, water and sunlight.

Rothschild’s team has tweaked the microbe’s genes so that it excretes some of the sugars to provide a food source for other modified bacteria, a system they have dubbed PowerCell.

The team has engineered a microbe called Bacillus subtilis to turn those sugars into a red pigment. Some B. subtilis will fly with PowerCell, and any colour change will be detected by an on-board sensor. That will show whether the bacteria are behaving as intended, as the satellite will not return to Earth, but burn up in the atmosphere after a year.

A key question, says Rothschild, is whether the Anabaena spores will germinate when rehydrated on the satellite. She has more faith in the B. subtilis spores, which have been tested in space before.

The satellite will carry experiments for more conventional food as well. In another first, the German team controlling the satellite will grow tomato plants by using bacteria and algae to turn synthetic urine into fertiliser, says team leader Jens Hauslage at the German Aerospace Centre’s Institute of Aerospace Medicine. Earlier this year the first lettuce grown from seed on the International Space Station was tasted by astronauts.

NASA says it plans to send people to Mars by the 2030s, although some say this date is optimistic. But whenever it takes place, the mission will need to be as self-sufficient as possible, says Amor Menezes of the University of California, Berkeley.

Still, Menezes points out that it is early days for space food. “Space engineers are very conservative,” he says. “Biology is something that has really not been considered yet.”

(Image: NASA)

Bacterial Origami E. coli bacteria have been engineered to make sheets of folding plastic. Astronauts on long missions might one day rely on such bacterial origami to make tools on the go. One way to save room on long space trips is to pack plastic sheets to be folded later. Manufacturing the material at your destination would be even better. To this end, Lynn Rothschild of NASA and her team have genetically engineered strains of E. coli to create plastic, which in turn can use ink or spores to fold itself into 3D shapes when heated. They presented their plastic creations at the International Genetically Engineered Machine competition in Boston in September. The team were inspired by plastic tableware in the NASA cafeteria, which they placed under heat lamps to see what kind of plastic would work best. Next, they figured out how to genetically engineer strains of E. coli to produce each type of plastic in the lab. They successfully folded simple structures including a box and a cup. In future, they envision more complicated items like solar sails or origami habitats. Aviva Rutkin

This article appeared in print under the headline “Mission Astro-food: Sugar to be made in space by microbes”