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Blood Protein Used to Split Water

Posted by Zonk on Fri Dec 01, 2006 04:53 PM
from the what-else-are-you-going-to-use-it-for dept.
brian0918 writes "The Imperial College in London is reporting that genetically-engineered blood protein can be used to split water into oxygen and hydrogen. The abstract can be viewed for free from the Journal of the American Chemical Society." From the article: "Scientists have combined two molecules that occur naturally in blood to engineer a molecular complex that uses solar energy to split water into hydrogen and oxygen. This molecular complex can use energy from the sun to create hydrogen gas, providing an alternative to electrolysis, the method typically used to split water into its constituent parts. The breakthrough may pave the way for the development of novel ways of creating hydrogen gas for use as fuel in the future."
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  • by Disoriented (202908) * on Friday December 01 2006, @04:54PM (#17073268)


    Now we just have to figure out if the amount of energy needed to synthesize the blood protein (say, X liters of hydrogen in a fuel cell) is less than
    the energy of the hydrogen produced from this process... :)


    --
    Rare 680X0 and PowerPC posters! [ebay.com]

    • Re: (Score:3, Interesting)

      Well, we're getting pretty good at genetically engineering simple organisms to produce things like this on their own.... (think BT corn).
        • by catbutt (469582) on Friday December 01 2006, @05:32PM (#17073908)
          Given that its from a living thing anyway, it seems like if breaking down hydrogen and oxygen in mass had any survival benefit, natural selection would have figured it out already.

          Obviously, caution is always needed in genetic tinkering, but still....I think the knee jerk "OMG its going to zap all our oceans!" is unwarranted.
          • by CorSci81 (1007499) on Friday December 01 2006, @05:43PM (#17074096) Journal
            It has, it's called photosynthesis [wikipedia.org]. Granted, here you're not liberating free hydrogen. But to counter the GP argument of using up all water on earth... can you imagine how incredibly unstable the local environment would become for one of these organisms in the wild? They'd be very liable to kill themselves off either through pH changes or simply setting their environment on fire if they reproduced unchecked. That combined with the fact you could never split all the water on earth faster than it will recombine if sunlight is your only energy input.
        • Re: (Score:3, Informative)

          Umm . . . we already do this? Check it out [wikipedia.org].

          Net loss of 1 H2O molecule in the Krebs Cycle. And plenty of other places as well, I assume.

          It's impossible, one presumes, for any standard cellular organism to destroy all water in its environment, because then no biochemical processes could occur and it would be dead.

          I presume the way this works is that they isolate the protein, rather than adding the organism to the water. And proteins don't self-replicate.

        • by Coryoth (254751) on Friday December 01 2006, @05:50PM (#17074228) Homepage Journal
          I think we (collectively) need to reevaluate the risk factors here; such an organism in the wild could very well turn our planet into a dustbowl in such a shockingly short time we wouldn't even have time to lynch the scientists who created it (think: hours - the mathematics of unchecked reproduction are truly alarming).

          Who said anything about reproduction, let alone unchecked reproduction? The article says it is a molecular complex, not a living organism capable of reproduction. I expect it is just an enzyme to catalyse the reaction, so I wouldn't worry about this any more than you would be inclined to worry about naturally occuring cellulase [wikipedia.org] suddenly going rampant and destroying all plant life on earth in a matter of hours. Generally being somewhat informed is a prerequisite critical analysis of risks and any ensuing scaremongering (okay, that's not true, i just think it should be a prerequisite!).
        • Re: (Score:3, Interesting)

          such an organism in the wild could very well turn our planet into a dustbowl

          So why haven't trees stripped every ounce of Carbon Dioxide from the atmosphere?

          Because there is more to a chemical process than one input (such as water).. For photosynthesis, there are many chemicals and input sources that are necessary. Sunlight being the most critical element, as it's what provides the energy.

          You can do some simple math to figure out how much energy would be necessary in a 100% efficient environment to convert
    • by Chris Burke (6130) on Friday December 01 2006, @05:09PM (#17073524) Homepage
      I'd be willing to bet that this compound can be used to break multiple water molecules, just like our hemoglobin can carry another oxygen molecule after it drops one off. The source of energy that allows continued hydrogen production is the sun.

      In which case, the main question is the rate at which you can produce hydrogen. How much of the substance do you need, and how much solar energy, to produce how much hydrogen over what period of time? That is what will define whether or not this is a practical method of producing hydrogen. One obvious point of comparison would be an equal-sized photovoltaic solar cell and water electrolysis machine. If it doesn't do better than that, it's pretty worthless. On the other hand it might be a very efficient way to convert solar energy into hydrogen gas for fuel cells, which would be sweet.

      Not to mention the other possibilities it opens up in biochemistry. These proteins are fascinating, as is the idea of swapping out the bound metal atom to get different effects.
      • by sillybilly (668960) on Friday December 01 2006, @06:53PM (#17075270)
        Yes, but most biological matter is easily degraded by UV radiation, plus infection - bacteria would love to feast on your new solar cells.
        As a sidenote, to quote the artilce: "Dr Stephen Curry Opens in new window, a structural biologist from Imperial College London's Division of Cell and Molecular Biology who participated in the research explains: "This work has shown that it is possible to manipulate molecules and proteins that occur naturally in the human body by changing one small detail of their make-up, such as the type of metal at the heart of a porphyrin molecule, as we did in this study.
        Naturally occur in a human? I was hoping they'd be talking about cow-derived materials, unless they are interested in genetically engineering photosynthetic human beings? Maybe one of our great great grand children will be engineered enough to be vacuum resistant and fully photosynthetic, then he can fly around in outer space while living off of sunshine.
    • Re: (Score:3, Interesting)

      Actually they say it far surpasses the current method of separation and assuming this is a passive process (much like solar power), unless the production costs are over a million dollars for one unit, the time it would take to pay for itself is nominal.
      • Re: (Score:3, Informative)

        Actually they say it far surpasses the current method of separation and assuming this is a passive process

        They say nothing of the kind. Quote from the abstract, "The efficiency of the photoproduction of H2 was greater than that of the system using the well-known organic chromophore, tetrakis(1-methylpyridinium-4-yl)porphinatozinc(II ) (ZnTMPyP4+), under the same conditions."

        Note the complete lack of superlatives.
        • Note the complete lack of superlatives.
          So greater!=surpasses? I'd suggest a dictionary if I thought you literate enough to even understand what a superlative is.
    • Now we just have to figure out if the amount of energy needed to synthesize the blood protein

      How much energy is required for pig farm?

      Genetically engineered pigs that is...
    • by Pedrito (94783) on Friday December 01 2006, @06:23PM (#17074774) Homepage
      Though it doesn't specify, it's highly unlikely that albumin or porphyrin is used up in the reaction. Instead, it likely cleaves the water molecules (the substrate). Not quite physically tearing it apart, but that probably isn't an entirely inaccurate description either. Many proteins perform functions like this on other molecules. They'll attach to part of the substrate and remove, say an -OH hydroxyl group, or some other piece of the molecule. This is how liver enzymes breaks down certain drugs so that the byproducts (called metabolites) can be removed from the blood by the kidneys. As someone else mentioned catalase from yeast, it works in a similar way and removes an oxygen molecule off of hydrogen peroxide, leaving water and oxygen, but the catalase isn't "used up" in the process.

      That said, proteins don't usually last forever and how long they last largely depends on how hostile their environment is, and what constitutes a hostile environment for a protein varies from protein to protein.
    • Re: (Score:3, Insightful)

      What really matters is how much this process drops the cost of separating water, not the energy efficiency.
      -jcr

      • Re: (Score:3, Informative)

        Yes, that's true if this were a closed system. However, this isn't a closed system. Energy is entering it (from the sun), and mass is entering and leaving (water, hydrogen and oxygen). So yes, total entropy is increasing somewhere, but it just isn't in this hypothetical system
        • Hydrogen is a non-starter, even with this technology. Why? Simple physics: it takes more energy to unbond water than you get back from burning the hydrogen and thusly re-bonding it back into water. Period, end of story. It's a little thing called the Second Law of Thermodynamics. Deal.

          Hydrogen is a Really Bad Idea.

          Nothing can contain it, storing it (as a supercold liquid) takes enormous amounts of energy, and, at root, it's got negative ER/EI. I don't care if it's in a portable form - IT'S NOT A SUST

  • by User 956 (568564) on Friday December 01 2006, @04:57PM (#17073312) Homepage
    The Imperial College in London is reporting that genetically-engineered blood protein can be used to split water into oxygen and hydrogen.

    I can hear it now... "No blood for oil! or hydrogen!"
  • I wonder how this compares to other methods such as solar power? Do you have to refuel this? How expensive is it to produce, install, and care for compared to solar panels. Makes me think of the book Distraction - maybe it'd be a good method for people that have time to care for it but not a lot of money?
    • by kebes (861706) on Friday December 01 2006, @05:38PM (#17074008) Journal
      I'm reading over the actual article right now. It seems that process is quite efficient. In the conclusion of the paper they note:

      Currently, rHSA(wt) is manufactured in an industrial scale, which allows us to use this zinc-protein photosensitizer in practical applications
      Thus the raw materials are cheap enough that one could imagine scaling this up significantly. Moreover since its behavior is catalytic, the protein isn't used up, so you wouldn't need to replace it very often.

      With regard to efficiency, in the Abstract they also point out that their system is more efficient than the previous standard in organic photo-synthesis:

      The efficiency of the photoproduction of H2 was greater than that of the system using the well- known organic chromophore, tetrakis(1-methylpyridinium-4-yl)porphinatozinc(II ) (ZnTMPyP4+), under the same conditions.
      Since the discovered system is a photosensitized catalyst, it effectively is a new kind of solar power. However it is one that directly generates H2 from incident light, without requiring one to harvest light energy as electricity, store it, and then use it to split water. So this discovery, coupled with cars/devices that run on H2 efficiently, seems like a viable idea. Of course we'll have to wait and see whether this really pans out, but from this paper it does indeed seem that this is a feasible way to harvest solar power (and store it as H2).
      • Not sure about the recombinant albumin, but part of my job involves pharmaceutical purchasing, and a vial of 20mL of 25% human serum albumin can be obtained for approximately $13. The human version is produced by precipitation from donated blood and is used quite routinely in the hospital to treat various conditions such as shock or malnutrition. Also, many medications are packaged with albumin in the vial (to provide a binding surface for the drug molecules).

        I would say though that the "manufactured i
    • Re: (Score:2, Funny)

      > Do you have to refuel this?

      Yes, but they are still wondering if it's better to refill this stuff with water, or with human bodies...
  • by javelinco (652113) on Friday December 01 2006, @04:59PM (#17073344) Journal
    I eagerly await the return to the days of human/animal sacrifice. "It's for the good of the country! We need to have more SUVs on the road!" Bow down, I say!
  • Desalinization (Score:5, Interesting)

    by Absolut187 (816431) on Friday December 01 2006, @05:01PM (#17073402) Homepage
    This would also make desalinization/decontamination pretty easy right?
    Just seaparate the H from the O, capture the gases, recombine into clean water.
    • Re: (Score:2, Interesting)

      If we're lucky, you'd not only get clean water, you'd get an abundance of (clean, perhaps?) energy that could be converted to electricity.
      • Re: (Score:3, Insightful)

        Actually, I thought the abstract said that the compound used is oxidized, meaning that the oxygen is captured and only the hydrogen is released. If I read the abstract wrong, please correct me.

        My (admittedly layman's) understanding is thus: they have a molecule that sticks to oxygen. Put the molecule into water and it grabs the oxygen away from H2O, releasing H2. That by itself is not very impressive. Sodium does something similar. So here's the cool part, when exposed to sunlight, the molecule releases
  • by b0s0z0ku (752509) on Friday December 01 2006, @05:01PM (#17073408)
    Blood also contains a protein called catalase. It makes the hydrogen peroxide that you put on a wounds bubble up with little oxygen bubbles. Yeast contains the same protein. Mix yeast and 3% peroxide solution and you get ------ oxygen and water. Stick a burning match in it and it burns with a bright white flame like a welding torch.

    -b.

  • efficiency (Score:5, Informative)

    by drDugan (219551) * on Friday December 01 2006, @05:02PM (#17073424) Homepage
    The mention efficiency many times in the article, but do not mention the most important efficiency number - that is total energy in/out.

    So, a quick calculation of efficiency:

    FTA

    Light in:
    6 hours, 450 W light = 2.7 kWh

    H energy out:
    0.044 mL H ... at 4.7 MJ/L (Wikipedia) * 1/1000 (L/mL) * 1/3.6e6 (kWh/J) * 1e6 (J/MJ) =

    = 5.7 e -5 kWh

    Disclaimer:

    This probably has an error, please help me correct it.

    It has been a really long time since I did physics or dimensional analysis.

    I could not find in the paper the pressure for the 0.044 ml of generated hydrogen, nor it's weight, so I made a gross assumption the energy density listed in Wikipedia (at 700 bar) was close enough.

    Regardless, if you put in 2.7 units of energy and get out 0.000057 units... that seems really (s)low.

    • Re:efficiency (Score:5, Insightful)

      by TubeSteak (669689) on Friday December 01 2006, @05:10PM (#17073540) Journal
      Regardless, if you put in 2.7 units of energy and get out 0.000057 units... that seems really (s)low
      Even if your math is off, it might not matter if the process can be scaled up, since solar power is cheap/free.

      The important question is how cheaply can they synthesize the needed protein.
      • Presumably this protein catalyst can be manufactured on a much larger scale than solar cells.

        Solar energy is free (well. .. as "free" as the square-footage of land on which you situate your collectors) - but solar CELLS aren't free.
  • What does your car run on?

    Mine runs on blood, sweat and tears! =) /stupidity
  • Doomsday weapon? (Score:3, Interesting)

    I wonder if you could bioengineer a plant that could survive in the ocean similar to seaweed, which would secrete this chemical. Eventually all the oceans would turn into Hydrogen and Oxygen... and LIFE WOULD BE DOOMED! Bwahahaha

  • However, one of the scientists went too far, and replaced every iron atom at the center of his porphyrin molecules with zinc, transforming him into Hydro Man -- but only when he went out into the sunlight.
  • Don't anyone tell the Machines about this, otay?

    So, all we gotta do is ship water up into orbit at $10,000 per pound and gain access to 24 hour light, then let the hydrogen ships drop back down where we can pick them up.

    Or perhaps something more reasonable. If we do this, we can also probably eliminate salt mines with all the salt we'll be taking out of the water at the same time. Yay, no more salt mines!

    Now all we need is some of those nifty carbon nanotube wall fuel tanks to store enough hydrogen to make
  • Thank you! (Score:5, Insightful)

    by mapkinase (958129) on Friday December 01 2006, @05:16PM (#17073648) Homepage Journal
    I would like to praise the submitter for providing a link to a peer-reviewed article. Does not happen very often, worth mentioning.
  • Next: (Score:5, Insightful)

    by jafac (1449) on Friday December 01 2006, @05:18PM (#17073672) Homepage
    We'll need one of these that can split Oxygen and Carbon.

    (ie - remove Carbon Dioxide from the atmosphere, and plant the Carbon somewhere safe - like maybe in empty petroleum resevoirs, where it came from).
  • Finland made hydrogen fuel cells that they use for many things such as electricity when boating. They say it only takes 8 fuel cells to theoretically power a car, but the article I read was years old. I've been told Finland already has electric cars.

    Heresay, I do say.
  • I look forward to not having to breath anymore. I could just stand out in the sun and drink some water. Is there a chance that I'd split all the water in my blood and dessicate like a raisin? Then there is the matter of all that leftover hydrogen. Would I burst like the Hindenburg? Oh the humanity!
  • A gill pack would be nice for walking around on the other 3/4 of the planet.

    Though it's not the same, as I think fish get oxygen from dissolved free oxygen, not by splitting H20.

    What to do with all this extra hydrogen?
  • by quoll (3717) on Friday December 01 2006, @05:40PM (#17074050)

    I'm pleased to see alternative technologies to split water using sunlight, but the idea is not new.

    There is a group at UNSW [sialon.com.au] who have been working on ceramics which use sunlight to split water (via a process of electrolysis). It's still in research (mostly due to efficiency), but it's an interesting option if you're interested in this stuff.

    Their website is pretty sparse, but there is a story on them here [abc.net.au].

  • by fahrbot-bot (874524) on Friday December 01 2006, @05:56PM (#17074330)
    ...something on the bleeding edge of technology here on /.

    Ok, ok, OK. I promise not to post for the entire weekend, sigh.
    Damn.

  • by The Step Child (216708) on Friday December 01 2006, @06:05PM (#17074446) Homepage
    From the abstract:
    In the presence of the colloidal PVA-Pt as a catalyst and triethanolamine (TEOA) as a sacrificial electron donor, the photosensitized reduction of water to H2 takes place.
    My chemistry knowledge isn't really up to the point where I can fully understand the whole abstract, but it sounds like we still need triethanolamine as a source of electrons in order to reduce water to H2. So the energy needed to produce more triethanolamine could put a big dent in the net energy gained from the H2 produced when we're talking about the practical large-scale usefulness of this. Maybe one day we could use another (renewable) electron donor like NADPH, so that we can couple it to another biochemical process like photosynthesis in order to renew our electron donors :)
  • by alchemist68 (550641) on Friday December 01 2006, @09:26PM (#17076892)
    Porphyrin chemistry is very interesting and has been studied for over 100 years. This news is both exciting and old news, because porphyrins and related isomers have been the subject of continued research. For very detailed information about porphyrin chemistry, refer to The Porphyrins edited by David Dolphin. Also, review the research of Martin Gouterman. In biological systems, porphyrins are found commonly in heme-type proteins used for oxygen transport and cytochrome P450 in the liver for metabolizing biological compounds including pharmaceutical products, and as chlorophyll in plants. Porphyrins have served as catalysts for organic reactions in industry, photodynamic therapy for cancer, molecular devices including sensors and switches, and model compounds for the active sites of enzymes. My thesis, which available for download through OhioLink:

    http://www.ohiolink.edu/etd/view.cgi?akron11339504 18 [ohiolink.edu]

    details the photophysical characterization of N-Confused tetraphenylporphyrin and characterization of zinc N-Confused tetraphenylporphyrin.

    Upon reading this post on Slashdot, I was pleasantly surprized that the subject of my thesis has some similarities to a related compound that could be used for further research into catalyzing an energy source. In one way I'm surprized, and in another I'm not, and I'm glad that one of the Slasdot crowd submitted the post. Porphyrin chemistry is vast, interesting, and complex.

    Happy reading!
  • Sacrifical Donor (Score:3, Interesting)

    by Roxton (73137) <roxton AT gmail DOT com> on Saturday December 02 2006, @12:17AM (#17077964) Homepage
    n the presence of the colloidal PVA-Pt as a catalyst and triethanolamine (TEOA) as a sacrificial electron donor, the photosensitized reduction of water to H2 takes place. [Emphasis mine]
    Isn't this a problem? How do you restore the triethanolamine without using energy?