Rothamsted Research

, the the two tobacco plants appear identical. Peer deep inside the cells of those leaves, though, and you'll see that one plant has powerful molecular machinery borrowed from bacteria. This feat of genetic engineering could turbocharge the natural process of photosynthesis, paving the way to faster-growing and higher-yielding crops.

Geneticists and molecular biologists have long been trying to meld the photosynthetic abilities of cyanobacteria—single-celled creatures once known as blue-green algae—with plants. The reason is simple: Cyanobacteria are far faster and more efficient at converting sunlight into usable energy than corn, wheat, rice, or any other plant. That's partially because the sun-loving bacteria use an upgraded version of a vital enzyme, called rubisco, that builds food out of CO2.

If agricultural plants could perform photosynthesis at the bacteria's pace, scientists say, it would cut fertilizer needs and increase crop production by 35 and 60 percent. And while countless research teams have tried and failed at this feat of genetic engineering, today a team of British and American biologists have announced they've successfully completed half the puzzle: they have grown a tobacco plant with genetically engineered cyanobacteria rubisco.

"Hearing the results of this experiment for the first time was definitely one of those 'Euerka!' moments you live for as a scientist," says Maureen Hanson, a biochemist at Cornell University that led the American side of the experiment.

When asked why her team of scientists succeeded where other's had failed before, Hanson points to the team's broad-stroke approach. Not only did the scientists swap in the bacterial genes that code for the turbocharged rubisco, but they also made several other genetic substitutions to include proteins that manufacture the rubisco.

The Oxygen Problem

While this is an impressive leap toward super-efficient crops, Hanson emphasizes that they've only solved one side of the problem of getting plants to emulate bacteria. Alongside their turbocharged rubisco, cyanobacteria also have specialized in which to house these enzymes. Scientists have not yet managed to genetically engineer these protective shells into plants, and without them, Hanson says, the bacteria's rubisco functions rather poorly in the scientists' plants.

Here's why: The rubisco enzyme, as it snatches up the CO2 it will use to make food, has a tendency to mess up and grab oxygen instead. Grabbing the wrong gas not only slows down the enzyme, but also ruins the work already done. Plants evolved to deal with this issue by creating a form of rubisco that's slow and inefficient, but more careful in picking the correct gas. But cyanobacteria evolved a different solution: They use those aforementioned protective capsules to ward off oxygen, creating a tiny, CO2-rich environments for their rubisco.

With the protective capsules, the modified tobacco plants in the study actually grew more slowly than ordinary tobacco. Just to keep up, Hanson says, "we grew our [genetically engineered] plants in a CO2 elevated environment" with more 22 times the amount of normal amount of the gas, "and they still were growing slightly slower than the normal type plants."

The Looming Food Crisis

Still, though Hanson's team has its work cut out as it tries to solve the other half of the problem, experts see incredible potential in this advance. Dean Price, a leading plant geneticist at the Austrian National University (who was not involved with the work), says, "This shows that one of important elements toward creating faster [and more efficient crops] has already been achieved."

And it's just in time, Price says. From the mid-20th century onward, the crop breeding techniques and improved fertilizers and pesticides that sparked the green revolution have helped to keep food production in step with humanity's ever-increasing population of hungry mouths. "[But] the green revolution has basically started to run out of steam," Price says.

According to Price, simple calculations show that in the next 35 years, humans will have to nearly double the food output to match projected population growth. But we have begun to reach the genetic limit of crop production at the same time we're seeing rapidly diminishing returns for new pesticides and fertilizers.

No wonder, then, that scientists like Price and Hanson are pinning hopes on ongoing GMO experiments that may show us how to avert the looming food crisis (much in the way that the discovery of fertilizer production through nitrogen fixation skirted worldwide disaster in the 1910's). And it's not just about hacking photosynthesis. Hanson also points to other techniques aimed to improve crop efficiency, such as the use of leaf-bound nanoparticles.

"Who knows what's going to be the best way to solve this problem, I think we need to pursue all of these different areas of research," she says.

This content is created and maintained by a third party, and imported onto this page to help users provide their email addresses. You may be able to find more information about this and similar content at piano.io