Hacking Photosynthesis

The vast majority of life on Earth depends, either directly or indirectly, on photosynthesis for its energy. And photosynthesis depends on an enzyme called RuBisCO, which uses carbon dioxide from the atmosphere to build sugars. So, by extension, RuBisCO may be the most important catalyst on the planet.

Unfortunately, RuBisCO is, well, terrible at its job. It might not be obvious based on the plant growth around us, but the enzyme is not especially efficient at catalyzing the carbon dioxide reaction. And, worse still, it often uses oxygen instead. This produces a useless byproduct that, if allowed to build up, will eventually shut down photosynthesis entirely. It’s estimated that crops such as wheat and rice lose anywhere from 20 to 50 percent of their growth potential due to this byproduct.

While plants have evolved ways of dealing with this byproduct, they’re not especially efficient. So a group of researchers at the University of Illinois, Urbana decided to step in and engineer a better way. The result? In field tests, the engineered plants grew up to 40 percent more mass than ones that relied on the normal pathways.

That’s John Timmer at Ars Technica summarizing a paper by South et al. in Science. The experiment was done in tobacco plants but the same pathways are used in the C3 group of plants including rice, wheat, barley, soybean, cotton and sugar beets so the applications are large.


> RuBisCO, which uses carbon dioxide from the atmosphere

So you might then say carbon dioxide is the most important thing on Earth.

No, it is not.

Humans are the most important thing on the planet. Everything else doesn't even understand it's "here".

But vegans tell us that all mammals are sentient.

odor clorox

Good luck making a human without carbon.

"In field tests, the engineered plants grew up to 40 percent more mass than ones that relied on the normal pathways."

I for one welcome our new giant corn and pumpkin overloads, and wish them well on their colonization plans. I offer my services in bringing my fellow humans to heel, in exchange for their leniency.

I've always said "what the world really needs is cheaper tobacco."

Heh. But that's so 20th century. Think of the yield bump for marijuana plants.

Yes, the upside is world hunger becomes a quaint relic of the past. The downside? Remember Day of the Triffids, or that Avengers episode with the giant man-eating, mind-controlling plant?

To my vegetable masters,

@Known Fact clearly knows too many facts about your plans. His self-awareness is a threat. I do not associate with him. I offer this information so that you may dispose of him immediately. Send the ASSASSIN OF SILAGE to his location at once.

Your ever humble, bad-tasting, and obedient servant,

Hold on, I think there's someone at the front door

Return of the Killer Tomatoes

Giant Plants v Hyperintelligent Robots

Humans in the crossfire

Gray goo vs Green goo scenario? Whoever wins, we lose, just like in Alien Vs. Predator, which I, um...never saw, but remember the tagline.

The problem with gray goo was that it never did have a good energy pathway, especially not one to tear down buildings in minutes.

I can deal with 50% more plant growth.

Corn is a c4 plant, not a c3, so this change doesn't quite work straight up: Otherwise, they'd have tested on that first, and Bayer would have bought the license for 8-9 figures.

There's also just increasing plant mass isn't necessarily an immediate winner in corn: The plant is complicated, and a major change like this might not lead to better yields under regular, non irrigated conditions: Chances are that, even if the change worked as advertised, it'd still take a decade to commercialize something that takes full advantage of the change.

Either way, this is why GMOs are, in general, something that we'd be irresponsible not to work on.

I don’t know if they will be able to get it to work in a plant like hemp (or other plants cultivated for fiber) but I would guess that it might have its first applications in those kinds of plants, and might help make biomass more viable as a source of fuel.

If GMO plants disturb the the easily disturbed these plants will make them crazy.

Prepare for a backlash against plenty from vegatarian, nudist, anti-gmo, anti-vaccine, left-wing, communist sympathizing, anti-capitalist, warmunists hell bent on stopping technological progress.

The sky is falling on them.

I take issue with the first line in the quote. A vast amount of biomass doesn't use photosynthesis at all. It's just inaccessible to humans--we don't eat organisms that grow at hydrothermal vents, or lithophiles, or other extremophiles. Of course, all the biomass that humans CAN access has its foundations in photosynthesis, eventually. So this is more a pedantic quibble.

The issue I can see with this is fertilizer. Increases mass by 40% means you need a lot more nutrients per plant. And we're already having trouble with fertilizers. If this were applied to contained crops, however--such as hydroponic crops--the results could be truly revolutionary. We may actually be able to reduce the footprint of cropland necessary to sustain a civilization by a substantial amount, which has staggering implications.

we don't eat organisms that grow at hydrothermal vents


The next food fad: instead of trekking to that remote restaurant in the Faroe Islands for roasted puffin, foodies will journey to Yellowstone National Park to forage for thermophilic feasts.

We will be able to feed the third world 5 times as much as we do now. Imagine the billions! Say goodbye to the camp of the saints - there will be rivers of blood.

Well, someone's standing on Zanzibar. Global fertility has halved over the past 50 years and now stands at about 2.5 children per women. Around 2.1 is the replacement rate.

Except we don't need to reduce the footprint of cropland, apparently. Otherwise, most farming would be done like in the Netherlands right now, in greenhouses.

SoftBank recently made $200 million investment in a company whose business plan is to establish greenhouses on the outskirts of every metro in North America to grow high value food crops. The idea is that they can automate so much of the work, reduce inputs like water and fertilizers, cut delivery costs, and by being so close to consumers, reduce spoilage and extend shelf life so much that they are profitable and cost competitive with normal farms, and more profitable to grocery stores.

More fertilizer isn't needed for the gains since the efficiency of the plant is increased, meaning less wasted.

That doesn't sound quite right. The re-engineered plant can do a more efficient job of converting sunlight and water & CO2 to edible sugars, but it still needs raw materials like a supply of nitrogen. It doesn't sound as though anything about this gene-tweaking were allowing the plants to do a better job of foraging nitrogen from the air or soil.

I think that's one of the interesting empirical questions. If we're fortunate, the new catalyst will be more efficient in its use of nitrogen and other inputs as well.

You're surely right that the super-plants will run into a constraint or scarcity of something, be it nitrogen or whatever, that will slow their growth. What will be interesting to see is what that substance is, how much it retards their growth, and can it be mitigated by e.g. using reformulated fertilizers.

Like 'junk' DNA, quite likely, they will later discover that the waste byproduct was actually serving an important function. Such broadly distributed and evolution selected inefficiency is probably not an inefficiency, you just don't understand the full picture.

125 million years ago: “There has got to be a good reason why the ferns didn’t evolve flowers!”

As a person familiar with this work: there is a very good reason. These plants evolved photosynthesis in a CO2 rich O2 poor environment. The detrimental chemical reaction wasn’t significant then.

Yes, the catalysis works faster with higher CO2 concentrations. Oxygenation works against it.

Currently we have no evidence that 85%+ of human DNA plays any biological role, so most of our DNA is junk.

Sorry, that's not true. One specimen: https://www.scientificamerican.com/article/hidden-treasures-in-junk-dna/

He's saying about 10% has a biological role and arguing it could be much higher.

Just wait until this super enzyme finds its way into ... kudzu!

We'll finally have a green world. Plants able to leap over tall buildings in a single bound!

Kudzu actually lead me understanding evolution and mass extinctions at a deeper level. Working in the stuff for a while, I put together a thought experiment about "Green Goo"--a situation where the world is taken over by a single plant species. The question is, what happens next? Over a scale as large as a continent, such a plant would rapidly begin to diversify, as local variations would create strong selection pressures, strong enough to overcome gene flow.

I'd rather not see that thought experiment run for real, though. Kudzu is an ugly plant.

Easy, we just engineer the goats

But then the mutant super goats will run wild in the streets, headbutting our vulnerable children, and eating our carefully cultivated organic window boxes.

We will have to control their population with genetically engineered chupacabras, and who knows what happens after that?

We will control the chupacabras with pack of man's best friend, which is also the peak of our genetic engineering efforts to date.

Either that or if we get the Mexican paid for wall it will keep the chupacabras in Mexico.

Summary was wrong -- biomass was increased by 25%, efficiency by 40%.

My Paleo friends will have a cow when grain prices drop precipitously. More carbs
More GMOs. More fertilizer and water consumption. More petroleum usage. More obesity and diabetes.

Then of course is the "farm problem" of lower grain prices driving down revenues and expanding consolidation of agribusiness. More monopoly power!

Or maybe not. Lower prices would give land higher value purposes.

Your paleo friends have nothing to worry about. The animals they eat consume tons of grain, so meat will get cheaper too.

Yes, they will do fine. But they seem to enjoy telling other people how quickly they are killing themselves with carbs.

Wouldn't your paleo friends love to have a cow?

That was very much intentional. ;)

I think the description is a slight misstatement. RuBisCO is not a byproduct but an enzyme with end-product inhibitive traits. Gene modification seeks to increase catalysis rates or decrease oxygenation. This has implications of increasing the use of plants as carbon sinks as well as increasing crop yields.

Oh god another global warming hoax promoting lib. Why the heck do we need carbon sinks? So Al Gore can fly to Telluride and pick up another award?

2004 called and wants its Al Gore meme back.

Not at all. Anthropogenic Global Warming is a hoax. But that doesn't mean a CO2 sink is unwelcome. CO2 levels can rise naturally with adverse effects on the environment. Pollution is bad no matter what you believe about AGW.

So you think:
1. "CO2 levels can rise naturally with adverse effects on the environment."
2. "Anthropogenic Global Warming is a hoax."
This makes me think you are unaware of how combustion works. But don't worry. It took me a long time to work it out myself. So you know, I'll tell you that burning stuff like coal releases CO2 into the atmosphere, so it is possible for human activity to affect the concentration of CO2 in the atmosphere. This CO2 acts the same as CO2 from natural sources.

Another idiot lib who thinks humans can affect geological time scale effects. All to keep us under control. Well those days are over, #MAGA2020

Fortunately, we're too smart to fall for a hoax used to keep us under control. The sooner we get that wall built the better, right? Why just the other day I saw a Mexican dancing in Congress. If we found another one we could line them up and shoot them.

What I hate about libs is their refusal to face reality. They won't even do basic math. For example, world coal production last year was about 7.5 billion tonnes which is about about 60% carbon for 4.5 billion tonnes of carbon. When burned 2.67 grams of oxygen combine with each gram of carbon to produce CO2 so that is 12 billion tonnes of CO2 emissions from coal. Throw in CO2 from burning oil and natural gas and that's more than enough to account for the increase in CO2 concentration in the atmosphere.


There's no misstatement. Author says, "The key reaction catalyzed by RuBisCo can be simplified down to the following: it takes a five-carbon sugar and carbon dioxide, and it converts them to two three-carbon sugars."

A plant would only be a carbon sink if you buried it rather than eating it.

Carbon sinks on the human time scale are "bog common."

Have you heard of plant roots?

the constant berth of language

I for one found this astounding. I didn't expect survival of the fittest to leave so much on the table. And out-growing your neighbor by 24-40% is definitely leaving something on the table.

Indeed. Hundreds of millions of years of evolution failed to iron out some inefficiencies that a few nerds from Urbana could. Well, I guess that there might be some negative side effects involved.

Evolution doesnt solve problems. It is a mindless process of survival as a local optimum to current conditions. It is extremely slow and often comes up with inefficient surviving adaptations. We can certainly improve upon it based on our normative judgement.

At least the restaurants keep getting better.

Except for the loud ones with attractive women

" Hundreds of millions of years of evolution failed to iron out some inefficiencies that a few nerds from Urbana could. "

HAL helped the nerds.

Personally, I feel as though my external testicles are leaving something on the table.

So complicated is someone to tell only one person who loves him, who quickly ventures into nonsense. A small piece, carved, honed from her own tree, fertilizes her mind and moisturizes her plum.

So kompliziert jemandem, einzigen zu sagen, wie Mensch ihn liebt, der sich in Unsinn schnell begiebt. Ein kleines Stück, geschnitzt, geschliffen aus ihrem eigenen Baum , befruchtet ihren Geist und befeuchtet ihren Pflaum.

Semper ubi sub ubi.

Biofuels here we come. I dunno if this works on sugar, yet, but 40% increase just abut makes biofuels competitive with lithium and solar. I dunno about algae, but algae has a serious contamination problem which is holding it back. Maybe this research leads the way.

It was an interesting article. One thought was "Is tobacco the porn of agriculture?" and the other was will further innovations be reveals from cannabis growth research. I am pretty sure even pre-legalization a fair amount of effort was put into increasing yields (though often directed at THC content).

It's probably worth pointing out the article was less optimistic about results in other corps. It's promising but not as certain as Alex seems to suggest. The NPR article notes "Researchers will have to find out whether it means that a food crop like soybeans actually produces more beans - or just more stalks and leaves."

Promising though.

This is how you get Triffids people.

Many years ago when Washington State passed the first organic law in the world I was on the board writing the rules for organic which were subsequently mostly copied by all organic programs that followed including the national one in the 90's. I argued long and hard that GMO's ( which were new at that time) should be allowed in organic ag because I thought eventually there would be resistance to disease and increased nutritional uptake able to be bred into GMO strains and, if there were, and organic farmers couldn't use them we might be the last ones needing to use toxic chemicals while conventional farmers used GMO seeds to avoid the problems.
I lost that fight to the environmental zealots who were even then organizing against GMO seed.

Comments for this post are closed