Slashdot Mirror
New Bacterium Could Herald Bio-Batteries
Clever Pun writes "According to this BBC article, a newly discovered bacterium is able to convert 'uranium and other radionuclides dissolved in water to solid compounds that can be extracted.' It reduces (adds electrons to) positively charged metal ions, making them insoluble in water (making them easier to clean up), which creates small charges of electricity. It has been speculated that this bacterium could potentially be used in a sort of bio-battery. Matrix v0.1b, anyone?"
about directly producing electricity when you could probably extract uranium straight from sea water with the help of these babies? Probably even cheaper than buying it from third world countries in the long run.
What I want to see is a machine that operates
carbon + electricty -> food
in less labor and land area per calorie than farming plants.
No one would want to eat it now, especially not the organic farming fans (mmm... organic parasites, yum!), but don't forget we're multiplying exponentially still, and you can only pile on so much fertilizer.
For great justice.
Not saying evolution didnt happen, but someone explain how an organism like this bacterium could evolve due to "survival of the fittest?"
It's pretty simple really. This type of bacterium is decended from a line which figured out how to live on a new type of food that others could not. That's evolution at work. The fact that it "convert[s] 'uranium and other radionuclides dissolved in water to solid compounds that can be extracted'" is a nice side effect for us, but that has nothing to do with evolution.
I have my doubts that this sort of bio-battery will ever be useful on a widespread, large scale.
Even anaerobic resiration by the most efficient organisms yields under 50% of the potential energy in their food. Secondary reactions like this typically occur at a much slower rate than life-sustaining reactions. What this means is that a fairly high amount of nutrients will have to be supplied, and that the resulting current generated will be relatively small compared to the potential energy sent in.
I guess what I'm saying here is "don't expect a miracle bio-powered car from this."
These bacteria will no doubt be useful in cleanup of contaminated sites, though. Perhaps soil could be placed into large decontamination devices, and the resulting electricity could be used for low-output pumps that drip nutrients into the chamber. Then you'd have a useful, self-powered detox device.
Their bacteria Shenwala alga, reduces the iron from Fe(III) to Fe(II) ( uses the iron as oxygen in it's metabolism ) . Other bacteria ( Desulfovibrio Ferrireducens ( sp ) ) have shown to reduce uranium from U(VI) to the less soluable U(IV) and have been used to clean up mine tailing drainage by making all the uranium insoluable.
Since any chemical reaction that is not allowed to go to completion causes isotopic enrichment ( presumably the lighter isotope is the preferred reactant ) and metabolism by bacteria is really just a chemical reaction there is some enrichment there.
Other bacteria which oxidize iron like Thiobacillus Ferrooxidans have been used to leach uranium out of ores by oxidizing it to a soluable state.
Since any chemical reaction not completed results in some isotopic enrichment one might enrich U235 by, feeding the dissolved Uranium oxide produced by Thiobacillus Ferrooxidans from raw ore to the anaerobic Desulfovibrio ferrireducens where it would reprecipitate. Then feed the precipitated uranium oxide back to thiobacillus ferrooxidans to produce more uranium liquor to feed to desulfovibrio ferrireducens forming cascaded stages which would gradually enrich the U235 until it was useful for fuel rods etc.
The question is: how much energy does this take, and how efficient is the enrichment? How much sugar/light/whatever-these-bugs-eat do you need to feed them per stage and is it more economical energy-wise than other uranium enrichment methods already in use?
A home experimenter interested in developing this into a patentable process would be breaking the law by enriching uranium. After learning how to grow these beasties ( I'm sure they'd sell them to you since they are not dangerous ) you would have to measure the enrichment achieved bu sending a sample off to a mass spectometry lab. It would behove one to send the depleted uranium rather than the enriched uranium so as not to piss anyone off ( hope it wasn't the heavy isotope the bugs liked better! ). Then you could measure how much it costs you to feed the bacteria per kilo of metabolized uranium and compare it to the cost of existing enrichment methods by looking it up, and decide if you have something worth patenting. Profit.
Eat at Joe's.