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Researchers are analyzing the molecular pathways that plants use for photosynthesis.
Researchers have been trying for decades to improve upon Mother Nature's favorite solar-power trick — photosynthesis — but now they finally think they see the sunlight at the end of the tunnel.
"We now understand photosynthesis much better than we did 20 years ago," said Richard Cogdell, a botanist at the University of Glasgow who has been doing research on bacterial photosynthesis for more than 30 years. He and three colleagues discussed their efforts to tweak the process that powers the world's plant life today in Vancouver, Canada, during the annual meeting of the American Association for the Advancement of Science.
The researchers are taking different approaches to the challenge, but what they have in common is their search for ways to get something extra out of the biochemical process that uses sunlight to turn carbon dioxide and water into sugar and oxygen. "You can really view photosynthesis as an assembly line with about 168 steps," said Steve Long, head of the University of Illinois' Photosynthesis and Atmospheric Change Laboratory.
Revving up Rubisco
Howard Griffiths, a plant physiologist at the University of Cambridge, just wants to make improvements in one section of that assembly line. His research focuses on ways to get more power out of the part of the process driven by an enzyme called Rubisco. He said he's trying to do what many auto mechanics have done to make their engines run more efficiently: "You turbocharge it."
Some plants, such as sugar cane and corn, already have a turbocharged Rubisco engine, thanks to a molecular pathway known as C4. Geneticists believe the C4 pathway started playing a significant role in plant physiology in just the past 10 million years or so. Now Griffiths is looking into strategies to add the C4 turbocharger to rice, which ranks among the world's most widely planted staple crops.
The new cellular machinery might be packaged in a micro-compartment that operates within the plant cell. That's the way biochemical turbochargers work in algae and cyanobacteria. Griffiths and his colleagues are looking at ways to create similar micro-compartments for higher plants. The payoff would come in the form of more efficient carbon dioxide conversion, with higher crop productivity as a result. "For a given amount of carbon gain, the plant uses less water," Griffiths said.
Making the grid more efficient
Anne K. Jones, a biochemist at Arizona State University, wants to make use of the power that goes to waste during photosynthesis. On a sunny day, a plant's molecular machinery generates more electrons than the Rubisco carbohydrate-producing engine can handle. "A lot of those electrons get thrown away," she said.
In this sense, photosynthesis is like "a badly connected electrical grid," Jones said. She's studying ways to use biological nanowires to transfer the extra energy from the light-harvesting cell into another cell that's genetically engineered to produce fuel or food. The nanowires would be analogous to electrical transmission lines, distributing power from one part of the grid to another.
Jones said filaments found on the surface of many bacterial species, known as pili, could be adapted for this purpose. Other researchers have already been looking into using those filaments as the basis for bioelectronic circuits.
"Components in future systems need not even be biological, so long as they interface with the wires developed in this project, paving the way for hybrid biological/inorganic photosynthetic systems," Jones explained in an abstract for her presentation.
Creating an artificial leaf
Jones' research meshes with Cogdell's efforts to adapt the chemistry of photosynthesis ujsing synthetic biology. Cogdell's project, backed by Britain's Biotechnology and Biological Sciences Research Council, is aimed at developing an artificial leaf that produces a dense, portable fuel you could put in your car.
"We would aim to produce hydrocarbon fuel from carbon dioxide," he said. His favorite candidate is terpene, the main ingredient in the plant resins that are today distilled into turpentine. Under the right conditions, terpene behaves "rather like octane," Cogdell said.
He envisions a process in which carbon dioxide and water are chemically processed to produce a scummy sheen of terpene, which could be skimmed off and turned into fuel. Even though the end product is a hydrocarbon, the process would be carbon-neutral because of the CO2 capture, Cogdell said.
"We can't do it yet, but we have a dream," he told me.
Whether the future belongs to artificial leaves, or nanowired bacteria, or turbocharged rice, all these researchers believe that coming up with a better way to turn sunlight into energy is a crucial challenge for the next generation. They estimated that there was only a 30- to 50-year window for completing the transition from the fossil-fuel era to the age of total renewable energy.
Griffiths said the next generation will need more food as well as more fuel. He referred to the "green revolution" that has transformed global agriculture over the past half-century, and added that "what we now need is a new green revolution for the next 50 years."
Cogdell echoed that view: "This is one of the grand challenges that mankind faces," he said.
Do you agree? Which path will lead us out of the energy crunch, the climate-change conundrum and the fuel-vs.-food debate we're dealing with today? Please feel free to weigh in with your comments below.
More on the future of plants:
- 'Artificial leaf' makes real fuel
- Mimicking plant evolution proves fruitful
- Chinese automaker suggests photosynthesizing car
- Six green-energy ideas so crazy they just might work
More from the AAAS meeting in Vancouver:
- Answers ahead for physics' deepest mysteries
- Scientists revive sounds of Stonehenge and other sacred spaces
- Gas-drilling gaffes aren't unique to fracking, study says
Alan Boyle is science editor at msnbc.com. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter or adding the Cosmic Log Google+ page to your circles. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.
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Yes, there will need to be another green revolution but on a scale much much larger than the last one. Only about 1% of the water of the earth is available for us to use and it is becoming more polluted and less useful, fertile land is being destroyed at an increasing pace, fertilizer is becoming very expensive and the world's population keeps growing. Currently only Argentina and the U.S. export large quantities of grains. In 20 - 30 years there simply many not be enough to feed the world.
The problem with the "green" revolution is that it perpetuates the lie that we can have cars and computers and cheap clothes and food-all-year and not have a significant impact on the environment ("We just need the innovation/technology/knowledge!").
You know what a green vehicle is? Your own two feet.
journal journal... there were people that used to believe you would fall of the end of the earth if you sailed too far west. there were people that doubted man could reach the edge of space. do you want to be counted among those that doubted the human ability to go forth and conquer?
worse yet, do you want the technology to be invented by China or Germany, or a country other than ours? the country that comes up with the technology first will benefit from the abundance of high paying jobs that comes with a new technology.
also, when you walk, you produce carbon dioxide. the carbon dioxide you produce is offset by plant mass that produces oxygen. the problem with fossil fuels is that there is no offset, it is excess co2 that had been sequestered over millions of years.
journal, it's actually been shown that you conserve more when you drive than actually using your own two feet, because you need to consume more to create more energy for your body in order to use your own two feet more...not that i'm advocating using only your car, i mean, i'm pretty much against oil use...which brings up my own green solution...industrial hemp. it can replace fossil fuels, all coal use in power plants nationwide for electricity (which would end all coal mining as well), and end deforestation by logging...all while being renewable, sustainable, and takes only three months for a crop to grow to full-term...
The biggest problem is deforestation coupled with excessive wasting of fossil fuel(65 degree A/C in summer in Arizona, global aviation has got to reduce dramatically). With enough plant life and swamps, a lot of pollution and carbon can be sequestered.
wow Hey, you know what it takes to build a car? Metal, chemicals and tons upon tons of water. It takes factories powered by coal, it takes at times freight if you're shipping cars or car parts around the world.
You CAN'T have your fancy doodads and still be green.
Quit treating me like I'm some sort of moron.
Journal, really? It absolutely must be coal? Forever? Is that what folks thought when we energy was primarily wood based? I agree, you can't have the fancy doo dads with no cost, but I disagree that this is the only way to do it, and that there is no better way. There is always a better way.
But you'd have to make a biodegradable vehicle in a sustainable fashion on a scale that can rival Detroit and Toyota City.
I just don't see that happening. In order to curb further environmental destruction and roll back the clock on global warming we're going to have to stop consuming and start conserving. That means a complete change in mindset from large worldwide, mass producing factories (that must run on cheap hot fuel to keep up production: Hence, coal) to small locally owned, operated and fueled enterprises.
Not only will the greedy corps start a war if they were forced to do that, the consumers would howl about the destruction of modern society (which is precisely what is needed) as they would be forced from consuming to conserving.
I don't see it happening.
but it does not have to run on coal...we can replace coal use with hemp...and we can also build bodies for cars from hemp...in fact, when ford first created his car he used hemp plastic to create its body...
“Why use up the forests which were centuries in the making and the mines which required ages to lay down, if we can get the equivalent of forest and mineral products in the annual growth of the hemp fields?”
- Henry Ford
You missed that they would have to be small scale.
Or else you'll be chopping down forests to grow "green fuel" and other plant based materials.
Remember the Palm Oil debacle?
http://www.nytimes.com/2007/01/31/business/worldbusiness/31biofuel.html?pagewanted=all
For a brighter future, people will ned to give up mass production of just about anything. And that would mean giving up a lot of cheap gadgets and doing without a lot of personal conveniences. Don't see that happening.
not true at all...we have enough farmland right now laying unused to grow hemp in...we have programs where our government pays our farmers to set aside some cropland and allow it to lay fallow so we can use it just in case we would need that land for other uses:
SUMMARY OF ACTIVE AND EXPIRING CRP CROPLAND ACRES BY STATE
CONSERVATION RESERVE PROGRAM - MONTHLY CONTRACTS REPORT:
National Total:
57,540,187.6
https://arcticocean.sc.egov.usda.gov/CRPReport/monthly_report.do?method=selectState&report=ActiveAndExpiredCRPAcresByState&report_month=June-2010
Other Cropland
The remainder of total cropland—that portion not used for crops— was
used for pasture (62 million acres) or was idle (40 million acres) in 2002.
Much of the cropland used for pasture is routinely rotated between crop and pasture use, although the rotation period varies. Part of the acreage, however, is marginal for crop use and may remain in pasture indefinitely... Cropland used for pasture was 68 million acres in 1997, compared with a high of 88 million acres in 1969 and a low of 57 million acres in 1964.
http://www.ers.usda.gov/publications/EIB14/eib14d.pdf
it is not neccessary to gut our forests further in order to do what i'm proposing. hemp can grow in even the most marginal soil, and can even improve the soil after a few crops...hell, it'll even clean up polluted soil...so not only will it help us be cleaner, it will even heal our earth's soil...:
Water and soil purification
Hemp can be used as a "mop crop" to clear impurities out of wastewater, such as sewage effluent, excessive phosphorus from chicken litter, or other unwanted substances or chemicals. Eco-technologist Dr. Keith Bolton from Southern Cross University in Lismore, New South Wales, Australia, is a leading researcher in this area. Hemp is being used to clean contaminants at Chernobyl nuclear disaster site.
Phytoremediation: Using Plants to Clean Soil
http://www.mhhe.com/biosci/pae/botany/botany_map/articles/article_10.html
Do you understand the sheer amount of hemp that needs to be grown to make enough raw materials to supply cars to the whole world? Or are you just trying to sell me hemp?
Mass production cannot be achieved without environmental degradation. Even if all that farmland was used for enough hemp, how in the world do you plan to sustainably process it and get it to where it needs to go on a worldwide scale without burning huge amounts of fossil fuels?
i never suggested this for the world...i couldn't care less about other nations. i'm suggesting this for america on a nationwide scale...and you wouldn't need to burn huge amounts of fossil fuels once we phase fossil fuels out with hemp...of course it wouldn't be possible to do overnight, there would be a period of adjustment until we're able to do what i'm suggesting...and if the rest of the world wants to follow in our footsteps, then good for them. in no way am i suggesting that we coerce other countries into following our rules, i would much rather focus on our own nation, period, and help our own citizens, period. @!$%# the world.
Joe, didn't I discuss this with you before? We don't have the area needed to switch entirely to hemp, it'll take more area than what the US covers.
Again, I'm not against industrial hemp, it's just that you are giving it way way way too much false hope in what it could accomplish.
Mitchell
Journal - I completely agree, I don't see it happening either. A few hundred thousands of years ago or so, a creature evolved out of a bottleneck. The key to that creature's survival was the ability to exploit many sources in the environment. Likewise, the ability to use everything, and move on. This is what that creature still does. When we have plenty, we want more, to feed that primitive part of our survival instinct, that keeps us thinking, "what if there are no more later". What needs to happen, is evolution. Most of the time, this doesn't happen without a massive die off.
There is no silver bullet for any complex problem. Alternative energies and materials must be coupled with less consumption, and better waste management. A good book that illustrates this is George Monbiot's "Heat".
Who green?, China?, Indea?, Africa?, the Middle East?. Aint gonna happen. With the population doubling every forty years the majority of mankind is just going to polute itself into oblivian.
Oops, I misspelled India.
and "oblivion"
;)
What....? Scientists have taken care of "transforming the seeds" now they are going after "leafs" ?
Time to kick in more money into the U.N. via the IMF.
ido, your ignorance is showing, again
While revolutions can improve the world, they can also cause trouble and misery. When you play games with Mother Nature, you find she plays for keeps. We like to think we're the best thing since bread came sliced, but the fact is we're merely stepped-up chimps. Dinosaurs ruled the roost for millions of years, and look what happened to them. We may have a better brain, but considering what we've done to our home, it has created as many problems as it solved. We have made machines to save and improve our lives, yet we also are perfecting ways of killing each other, and we are treating our planet as both landfill and toilet.
The fact is we don't have to DO anything radical...we just have to learn to live within our means, as individuals and as earthlings. 'Cause the last time I checked, this is the only planet we can live on, and there is no Plan B!
I agree with you on many levels. I think we should just focus on using less energy and less resources which we have had a lot of success. I'm almost 40 now and I know I use less energy to complete my daily tasks(laundry, transportation, communication and recreation) than when I was a child due to our ability to increase the efficiencies of our tools. I still wonder if it is possible to have this life of convenience for the masses of 7+ billion and not be totally destructive to our world(as you say, the only one we know of). Well, in relation to this article... I'm amazed at the number of steps discovered in the process(168), reminds me of biochemistry class, painful!
An even more radical concept has been suggested by physicist Freeman Dyson. He suggests the possibility of "black plants" that use man-made genes that utilize photovoltaic energy conversion (10-40% efficient) instead of the realtively inefficient natural photosynthesis (1-2% efficient).
They still have not thought of just using the electrical conversion to turn leaves into solar panels for our electrical power grid.
And they never will??
No matter what science can do for us by way of increasing food and fuel supplies, it doesn't attack the key problem which is population.
Some way must be found to contain the growth of world population. Now, I am not proposing this but I think it should be considered. Since women produce all the children, maybe we only need to contain the number of women on the planet. Since killing or aborting the girl fetus is abhorrent to all of us, maybe something could be done to sex selection at the time of fertilization that would favor the production of males. Now it is 50-50. nudge it to 60-40.
I don't know how this could be done, but if it was done, we could have a controlled decline in population that wouldn't limit the number of children a woman has, and it wouldn't involve the killing of a fetus or infant. And, with the growing acceptance of homosexual behaviour and gay marrage, this may be right in line with our new norms.
Bill H: I'm not completely sure, but I remember reading/hearing in class as an undergraduate (Philosophy, I think.) that Plato considered homosexual behavior to be an effective means of controlling population and its growth. I don't remember whether the instructor went into any details, but your idea certainly appears to have respectable (spelling?) antecedcents (again, spelling?).
Anyone who's studied population growth seriously knows that the strongest factor in lowering growth rates is improved women's rights - primarily, education. Education allows women to see that they have alternative futures besides being their husband's maidservant, and it gives them reason to think and ask about the process of reproduction and the use of birth control. It's really no coincidence that the countries where populations are exploding (i.e., India, Afghanistan) are the most gender-oppressive, patriarchal countries in the world - and some of the poorest. Decreased population growth could be achieved by investing heavily in women's education and rights in underdeveloped countries, and by making birth control more accessible. Women who know there is more to life than being their husband's and children's servants are women who practice birth control and plan their pregnancies.
Finally. once done we will have all the hydrogen we can possibly use by plain old everyday photosynthesis. And HYDROGEN is the way to go. Everything else sucks in comparison. And to those who say too costly I say how obtuse can you get! They WILL solve the cost problem
Photosynthesis is JUST a process that CAN be copied
When iron rusts hydrogen is produced. Make the iron a powder and the process speeds up. Add a catalyst like salt and the process speeds up. It's JUST physics
Algae produce hydrogen when the photosynthesis process is interrupted
It's more in line with Chemistry.. they never get the appreciation.
Any technology that says it will be carbon neutral because of CO2 capture is bunk. Putting emissions underground has been found to create earthquakes and tremors and can be fraught with soil contamination problems that engineers cannot possibly anticipate no matter how well they study the ground mechanics of any given area. I"m all for green energy but storing CO2 underground must go away as an alternative.
Frederick222: I don't think the people in the article are espousing storing CO2 underground; they're espousing storing it in plants and in the soil, just like it is now as a part/product of photosynthesis. And, when the plants die, if they're entombed in the soil and eventually wind up deep underground, they become peat, and then coal. Think for a moment; these scientists aren't talking about anything remotely resembling fracking, as you apparently seem to think. No. They're trying to replicate a natural process.
Photosynthesis is cool - what fun research
The problem with "Green Revolutions" is that it fuels population growth, which necessitates further "Green Revolutions," until... it all falls down. Jared Diamond's "Collapse: How Societies Choose to Fail or Succeed" is instructive in its examination of extinct civilizations who chose 'Boom Then Bust.'
This would appear to be true, but when you look at population rates in the more highly development & educated nations, we see long term population rates decline over time. This is true for many European countries, Germany for example, the United States (excluding minority groups), Japan, etc. I see no reason to believe that as progress reaches other nations, and minority groups the same would not be true for them as well. That being the cause, the population problem, will eventually take care of itself over the next century or two. The problem is, will we have doomed our survival in the mean time by consuming all non-renewable resources? These green revolutions have the potential buy us the time we need.
Or we could just, you know, ask corporations and consumers to stop consuming and wasting uncontrollably and using up and destroying forests, rain forests, water, and natural resources. If we could simply preserve the *real* leaves, trees, and plants we have left and replant new ones, we wouldn't need to develop artificial leaves. :/
The artificial leaf is a concept that's been in the works for a while, probably most notably by Dr. Daniel Nocera at MIT.
Nocera's leaf is about the size of a poker card (but thinner), and is made of silicon, electronics, and nickel and cobalt catalysts – all materials that are relatively inexpensive and widely-available. Placed in a gallon of water in bright sunlight, it is said to be able to produce enough electricity to supply a house in a developing country for a day. It would be connected to a fuel cell located either on top of or beside the house.