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Self-Destructing Bacteria Create Better Biofuels

Posted by samzenpus on from the kamikaze-gas dept.

MikeChino writes "Researchers at Arizona State University have genetically engineered cyanobacteria to dissolve from the inside out, making it easy to access the high-energy fats and biofuel byproducts located within. To do this they combined the bacteria's genes with genes from the bacteriaphage — a so-called 'mortal enemy' of bacteria that cause it to explode. Cyanobacteria have a higher yield potential than most biofuels currently being used, and this new strain eliminates the need for costly and energy intensive processing steps."

17 of 139 comments (clear)

  1. Biofuels are the future. by purpledinoz · · Score: 4, Interesting

    Plants are the most efficient at collecting solar energy. Plants are the most efficient at storing energy as some form of hydrocarbon. We already have a huge infrastructure to distribute hydrocarbons. It's such a perfect fit. This hydrogen nonsense was a huge waste of money, and should have been invested in biofuels.

    1. Re:Biofuels are the future. by jcr · · Score: 4, Insightful

      Plants are the most efficient at collecting solar energy.

      I'm not sure that's the case, but what plants are, is cheap.

      -jcr

      --
      The only title of honor that a tyrant can grant is "Enemy of the State."
    2. Re:Biofuels are the future. by f3r · · Score: 3, Funny

      Plants are the most efficient at collecting solar energy.

      I would expect in the future some kind of battery cells which directly interface with a massive array of plant-emulating light absorbing complexes which produce a voltage from sunlight.

      Though in the Wikipedia I see (see 'photosynthesis') that this process converts light into energy with an efficiency of 3-6%, while solar panels have 6-20%, I believe that it might reach a point where mass production of hybrid organo-metallic devices can be achieved

      At the end we will have plants at home which instead of producing sugars, will have an electric plug. They part in the plant where electricity is produced will be called iPod.

    3. Re:Biofuels are the future. by TeXMaster · · Score: 4, Insightful

      Plants are the most efficient at collecting solar energy.

      I'm not sure that's the case, but what plants are, is cheap.

      -jcr

      Everything is cheap until everybody starts collecting it.

      --
      "I'm never quite so stupid as when I'm being smart" (Linus van Pelt)
    4. Re:Biofuels are the future. by Antique+Geekmeister · · Score: 3, Interesting

      Not according to this fellow, who won an Ig Nobel award for his work with bacteria from panda poop, who need to process quite a lot of cellulose in their diet. Hydrogen is the biofuel these bacteria produce.

      http://mdn.mainichi.jp/mdnnews/news/20091124p2a00m0na009000c.html

    5. Re:Biofuels are the future. by Marcika · · Score: 5, Insightful

      Photosynthesis extracts a whole lot more of the sun's energy per square meter than our best solar panels..

      No it doesn't. Most plants only operate at 1-2% photosynthetic efficiency, the most efficient crops maybe at 7%, and the theoretical maximum is 11%.

      Compare that to solar cells which have 15-20%, in the laboratory even 40% efficiency. The advantage of photosynthesis is not efficiency, but price and resiliency, with the "cells" manufacturing themselves.

    6. Re:Biofuels are the future. by jamesh · · Score: 4, Interesting

      You are comparing turning the suns energy into electricity to turning the suns energy into hydrocarbons and then turning that into electricity, and you are discounting the other uses for the hydrocarbons.

      Taking carbon out of the air and cracking water into hydrogen and oxygen takes a whole lot of energy and the plants do it better than they can in the lab, when the only energy input is the sun.

    7. Re:Biofuels are the future. by OeLeWaPpErKe · · Score: 3, Interesting

      *Ahem* the basic premise is wrong. Plants are NOT the most efficient at photosynthesis. In fact, plants, in the most narrow definition of the word, are incapable of photosynthesis.

      Plant cells do, however, contain a degenerate cyanobacter, there are a few different species but we call all of them "chloroplasts". Strictly speaking this part of plant cells is not actually plant in origin.

      Just like animal cells are not actually capable of digesting food, and using it to convert ADP into ATP. We do however contain degenerate cyanobacter that are capable of that feat, and who share their ATP with us. Strictly speaking, however, they are not "animal".

      Plant and animal cells are not, in the strict definition of the word, alive, since they do not really fulfill all of life's functions themselves. Specifically plants and animals both lack "inherent" digestive capacity. And without digestive capacity all other living activities would soon cease. Both families do have a symbiotic relationship with a more primitive lifeform that is alive. Plant and animal cells may be more alive than viruses, but they are not actually "fully" alive.

      Needless to say, the cyanobacter by itself is more efficient at photosynthesis than the entire plant cells. For starters, it captures a (much) greater portion of sunlight when not surrounded by a cell wall, and the food doesn't need to be shared with what is essentially a parasitic lifeform in this application. Normally the plant chloroplast relationship would be called symbiotic since the plant provides the chloroplasts with otherwise unavailable access to sunlight. However in this case it's direct human intervention that provides the access to sunlight.

    8. Re:Biofuels are the future. by Anonymous Coward · · Score: 5, Insightful

      What are you smoking? *Ahem* the basic premise is wrong. In fact, plants, in the most narrow definition of the word, are totally fucking capable of photosynthesis. Unless you just made up a definition of a plant. You see, its because plant cells do contain a degenerate cyanobacter that we call a "chloroplast." Strictly speaking, this part of plant cells is not actually plant in origin, but then if we're speaking strictly, neither is the DNA in the plant cells or the cell membrane or the cell wall because, you see, all of these come from these really old bacteria and the plant just STOLE them! And called themselves living things! Ugh, it makes me sick. "Actually," it doesn't matter that chloroplasts, a long time ago, were fully alive. It's kind of like how it doesn't matter that you, a long time ago, were a small child with the promise of being a productive human being. Now, chloroplasts are part of plants and you are a piddling excuse of a man.

      If you still don't believe me, consider: while chloroplasts were free-living cyanobacteria millions of years ago, they are now incapable of survival outside of the host cell; additionally, they cannot replicate without the host cell so they are "not actually 'fully' alive" either. Considering that a substantial portion of their DNA is also stored in the nucleus of the plant cell, one must really consider the chloroplast part of the host cell; that is why any biologist will say that chloroplasts are an organelle inside (some) plant cells. The same argument is applied to mitochondria: they are part of animal cells and thus, animal cells are alive. Trying to split the eukaryotic cells from mitochondria (or plant cells from chloroplasts) is like taking the creme filling out of a Twinkie; you can't because both parts are integral to the whole. Neither you nor your liver would survive very long without each other, and the same can be said for eukaryotic cells and mitochondria. (Obviously, this doesn't generalize to other organs as you are living proof that life can be sustained sans brain).

      Needless to say, the cyanobacterium itself is not necessarily more efficient at photosynthesis than entire plant cells. For starters, all plant cell structures except for the chloroplasts are basically transparent so all the sunlight absorbed by plant leaves is absorbed in the chlorophyll that is only present in the cytochrome complexes in the chloroplasts. Additionally, plant leaves have other structures that control the environment inside the leaf and let the "cyanobacteria" work better; think of it as how "humans" work play WoW much better in air conditioning than hot sunlight. Normally, the plant-chloroplast relationship would be called symbiotic since the plant provides the chloroplast with otherwise unavailable access to sunlight. However, in this case it's direct human intervention that provides the access to sunlight. it obvious that the plant and chloroplast both benefit from their arrangement, but you are an idiot who styles himself a genius.

      Also, can you please explain to me how it is "direct human intervention" that provides chloroplasts with sunlight? I didn't realize that we controlled the fucking sun...or is that because I one of the sheople manipulated by the secret cabal?

  2. Water is a scarce resource by mangu · · Score: 3, Interesting

    Plants are the most efficient at collecting solar energy. Plants are the most efficient at storing energy as some form of hydrocarbon

    I agree with you in that, but I don't think cyanobacteria are the only solution for biofuels.

    Pond scum needs ponds, and ponds are filled with water. Granted, waste water can be used, these ponds can be part of a sewage treatment system.

    I think a future biofuel system will be a more diverse system. We will need bacteria in ponds, but also other plants, such as cactuses or other that grow in semi-desert areas, for instance. Or what about the oceans? Imagine biofuel made from kelp, three quarters of the surface area of Earth are available for that.

  3. Evolution, suckers.... by Niedi · · Score: 4, Interesting

    As soon as even one or two bacteria manage to throw the phage-genes out again or, even simpler, acquire a loss-of-function mutation they'll have a huge advantage over the self-destructing ones and might eventually eliminate them. The result would be quite nasty for those who run the harvesting plant...

    I'd at least suggest seperated smaller tanks of bacteria that are isolated from one another so that the damage of such an event is kept at a minimum.

    1. Re:Evolution, suckers.... by Schiphol · · Score: 4, Insightful

      It makes some sense. The idea is that whenever you have a lot of bacteria reproducing, mutation rates being what they are, benefitial mutations will eventually appear. Something like this has been used to. Chemostats, which are what these things will essentially be, have been used to test evolution experimentally in just this way.

      Now, the flaw in Niedi's reasoning is that evolution is directed only be better differential reproduction. So, if bacteria reproduce before self-destruction, there will be no environmental pressure to select against this feature.

    2. Re:Evolution, suckers.... by sjames · · Score: 3, Informative

      A loss of function mutation in a yeast used for brewing or a yogurt culture would be a big problem, just not as sensational as a kill the consumer mutation. Yet maintenance and selective breeding of cultures has been manageable for centuries now.

      By the time the survival aspect of the modification can come into play, the bacteria are already at a dead end. They are in the batch that is being processed to fuel. The survivors of the nickle treatment will be destroyed just as surely as those that didn't mutate. Yields will be monitored. A tank whose yield declines will be sterilized and re-seeded. Culture sources with poor yields will be destroyed and replaced by others that have bred true (or at least haven't mutated in a way we don't like), just like yeast cultures. Those that produce bad beer are destroyed.

      Yes, they mutate a lot. Most of the mutations are a disadvantage. Of the remainder, most don't matter at all. Those that prove harmful to the purpose we culture them for are destroyed batch by batch. The very few that prove beneficial to our purposes are propagated.

      In many ways, culturing for fuel production is easier. Unlike foods, we don't care if it has an "off" taste, just that it burns well after processing.

      Consider, a brewing yeast that mutates so that it can oxidize alcohol for energy will find plentiful food as the others die out. By the end of the fermentation process they will easily dominate. However, they will produce nasty tasting beer. If the mutation happens in the culture rather than in the vat, the whole culture is discarded.

  4. Re:What's the worse that can happen? by TapeCutter · · Score: 3, Funny

    Have we ever had exploding bacteria before?

    Yes, but they don't make a loud bang so most people didn't notice.

    --
    And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
  5. more details by brokeninside · · Score: 5, Informative

    Science Daily has the full press release which is a bit more informative: Genetic engineering feat could greatly reduce costs and the full paper is at the Proceedings of the National Academy of the Sciences: Nickel-inducible lysis system in Synechocystis sp. PCC 6803 (if you have access that is).

  6. Wrong by Ignatius · · Score: 4, Informative

    No, the 11% max. figure is for just turning sun's energy into hydrocarbons. If you want to generate electricity out of it, like in a bio-mass power plant, the thermodynamic losses would be on top of that so the efficiency would be considerably lower.

  7. BacteriOphage by plasmidmap · · Score: 3, Informative

    It's properly spelled bacteriophage--which are viruses of bacteria. These viruses make bacteria 'explode' so that newly replicated virions are released into the environment.