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Toxic-Waste Consuming Bacteria
cswiii writes "CNN has this article about scientists who have created bacteria that consume toxic wastes, such as radioactive materials, breaking them down into less harmful compounds. " Similar work has been done before with genetically engineering trees. I believe that bactera that eats oil has been actually used in oil spills before.
Heh, interesting mental picture. Bacteria eating radioactive compounds, and crapping out same, contained in Boron-infused buckyballs. Possibly bonded with Iron, or some other compound that would make it easier to separate from soil|liquid, and physically contain.
A ChemE friend of mine is working on a method of purifying chemically contaminated water by mixing fine Iron fillings into it, and running it through a variable magnetic field. Apparently this works extremely well for many contaminants, and is quite cheap to do (once you've got a site built, that is). Hence the above Iron idea.
-- What you do today will cost you a day of your life.
Think about the thermodynamics of the situation for a moment. The plants produce energy, the energy comes from converting radioactivity into heat. So the total amount of radioactivity has to decline, right?
Ah, but why is the stuff sitting above ground in barrels? Because everyone is too nervous about putting it back into the ground somewhere, because it might leak out somehow or other. What about the danger of the natural ores "leaking"? You never see these two compared... the radioactives are supposed to just magically appear as a by-product of the nukes. Check. It does appear that the original poster knows more about this than I gave him credit for.So let me address "the issue", which is evidentally that prevention is better than repair. But is there really a difference? The clean-up technologies don't neatly separate from the production technologies. For example if you're really good at cleaning up stray particles of radioactive metals, you may be able to do it inside the gates of the plant. So that's prevention, right?
And then there's the question of prevention of *what*. The whole energy business is part of a centuries old effort to prevent things like death by exposure, starvation, etc (it's not all about racing around in SUVs to sit in front of CRTs). Would it have been better to have, say, never learned to burn coal?
Unless you're some sort of anti-human "deep ecologist" or something, the answer is "hell no". The history of technology is a history of juggling evils, ameliorating some problems at the expense of causing other (hopefully lesser) problems, which we may then ameliorate at a later date. Over the centuries, this juggling act has clearly been a big win for the industrialized world, more than doubling our lifespan and changing our lives from a hand-to-mouth existance to ones with the luxury to waste time scoring debating points on slashdot.
That this bacterium can withstand such high levels of radiation is truly unique. However, not much else about it is. Bacteria are routinely used in site cleanups. The most common use of bacteria is the degradation of organic compounds, primarily hydrocarbons. In this case, the hydrocarbons are aerobically transformed to carbon dioxide and water. Other compounds are also biodegradable to more or less extents. Chlorinated compounds are difficult (primarily due to the steric hindrance caused by the large chlroine atoms), but are subject mainly to anaerobic degradation through reductive dechlorination, or cometabolic degradation.
Now what this article is discussing is a bacterium that transforms mercury. There is also a lot of literature about "metals biodegradation", but of course, metals are elements, and can not be destroyed. What happens in "metals biodegradation" is that the metals are transformed into different oxidation states that are less toxic or harmful. For example, hexavalent chromium is significantly more toxic than the trivalent form.
In the case of mercury, the main concern is methylated mercury versus elemental or ionic mercury. Methylmercury is the most toxic form since it can bioaccumulate (essentially acting like an organic due to its methyl groups) and thus more easily get taken up ny living organisms (nothing is toxic to you unless you get it in your body by ingestion, inhalation, or through dermal absorption. This excludes radiation, of course). So I am guessing that this bacterium somehow demethylates methylated mercury. It probably produces elemental mercury (i.e. liquid mercury) which is less likely to be ingested, or else some sort of mercurous or mercuric salt that is insoluble (mercuric phosphate, maybe?) and not likely to be remetabolized into the methyl form.
Bioremediation has been around as long as there have been septic tanks and cesspools - it is certainly nothing new.
The concept of engineering organisms to do this has been around in the '60s.
The first person to do this using early genetic engineering methods was Dr. Ananda Chakrabarty. He used a method of selection to develop a bacterial culture that feeds on PCB's in the late 1960s.
Dr. Chakrabarty later became famous because he became the first person to patent a genetically engineered life form. The case (Diamond vs. Chakrabarty), ultimately decided by the Supreme Court was fought tooth and nail by the patent office. It is one of the landmark patent cases of the 20th century. US 3,813,316 is the patent number.
I'm not sure if this is being done, but, one good thing about creating your own life is creating a way to make these life easily destructable.
However, unlike Jurassic Park, it can be done in such a way (by inserting DNA of certain protein defficient bacteria) that it is certain they can be killed with anti-biotics. With this insertion, it can also be assured that the trait is not mutatable.
I could be wrong, but, a mutation like this doesn't seem to be covered in the primitive reproductive act of bacteria, only in archaea and eukarya.
The explanation, of course, is a lot more complicated dependent on what type of bacteria (gram-negative or positive) are being used and what the cell-wall composition is. NAM-NAG, B4, etc.
How?
:)
A mutation like what?
If a bacteria begins as succeptible to certain antibiotics, the only way this can be changed is through the lateral gene transfer you refer to. Basically, this is done in most bacteria by the exchange of plasmids between bacteria. Plasmids are composed of DNA and exist on and around the cell-wall of all bacteria. These plasmids encode enzymes that break down organic material, and also encode enzymes that destroy antibodies.
This is a trait present in both gram-negative and gram-positive bacteria, and is how anti-bacterial resistance is passed (penicillin, etc.)
What is being theorized -- and what the control relies upon (AFAIK)is that you can somehow inhibit these plasmids from exchanging -- *given that you are creating this organism*. How this is done, I don't really know.
So, what I'm saying is that a bacteria can't mutate to change its cell wall and the composition of it. It can be changed in a very specialized way to become resistant to certain chemicals (as with anti-biotic resistance), and this is why plasmid exchange must be inhibited.
I think.
While some amongst us might think it silly, there were recently two men killed in Tacoma, Washington by flesh-eating bacteria. It was carried on the AP and Reuters wires and just happened.
One of the problem with antibiotics is that many strains of bacteria and virii are becoming immune to commonly-used antibiotics, to the point where doctors are now warned not to use the "new" antibiotics except when they know the infectious agent is already immune to the commonly prescribed antibiotics.
More people died from the Spanish Flu than from WWI, after all. And more people died in WWII from disease than any other cause.
Without antibiotics, many of the advances in civilization would have probably not survived. It gave us this breather until we could start working on genetic defenses and tailored anti-viral agents.
Will in Seattle
Ok folks, here's the problem: It is not OK to be making all of this radioactive crap in the first place. Sure, I know, we all need energy and nuclear is cleaner than blah blah blah..... but really this is how we get into this mess in the first place. A lot of technology only exists for fixing the problems that we created. I so much wish that instead of sprawling out all over this planet we would stop and look at what we are doing to ourselves and our lives. Technology is fun and all but at what cost?
Americans have horrible diets. They eat 50% more meat than 100 years ago and 50% less fruit/veggies than 100 years ago because meat used to be somthing special that you couldn't afford to eat every night. Now, what is the answer to america's health problems? (Jeopardy! music)
What are: fat burning "natural herbal remedies", fat blocking drugs, and WOW! Potato Chips!
This whole get rid of nuclear waste problem should really be: Let's find ways not to produce so much nuclear waste. While we are at it: Let's find ways to eat better, Lets find ways to live healthier, and Lets find ways to see problems as being caused by something preventable.
I am tired of the band-aid, "shoot those cows full of antibiotics so we can treat them worse without killing them; their antibiotic resistant bacteria will never travel to humans" kind of mentality. The problem isn't that we have oil spills. The problem is that we haven't genetically engineered enough oil eating bacteria. I try to eat organic but it costs 2x as much. You know what, I think it is worth it knowing that I at least try to support sustainable farming practices.
Humans are so egocentric. All of theese huge corporations run by arrogant jerks. The problem with self made men (and women) is that they tend to worship their creator. At least some corporations have some conscience.
-pos
The truth is more important than the facts.
The truth is more important than the facts.
-Frank Lloyd Wright
Breaking down a chemical compound does not change anything about the nuclei of the atoms from which it is made. If you have radioactive technetium salts and you convert them to technetium metal, it is still going to be just as radioactive as it was before. What changes is its solubility and other chemical properties. In the case of technetium the metal is insoluble, so you can immobilize it (and prevent it from leaching anywhere) by reducing it to the metallic state.
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Time is Nature's way of keeping everything from happening at once... the bitch.
- Tritium (metabolized to water vapor)
- Carbon-14 (metabolized to radioactive CO2)
Radon and xenon are already gases (noble gases at that), so it makes no difference; they're already gone. Most radwaste is composed of alkali metals, alkali earths and transition metals with the occasional halogen thrown in (astatine, I-129, I-131). These will not be metabolized to gases, so they'd have to escape some other way.--
Time is Nature's way of keeping everything from happening at once... the bitch.
If you'd read the article you'd know that D. Radiourans has been around for a couple billion years. Our entire evolution, from H. Sapiens Sapiens back to the first vertebrate, has been in an environment with D. Radiourans in it. You can stop worrying now, it's okay.
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Time is Nature's way of keeping everything from happening at once... the bitch.
Oil-eating bacteria have evolved quite naturally; you'll find them anywhere there are natural oil seeps. After they do their job, they become food for other things. Playing God? Well, yeah; if God had decided to play with supertankers full of crude, He would have made a hungry bug to eat the spills too! It's our problem, though, so we get to make the means to fix it.
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Time is Nature's way of keeping everything from happening at once... the bitch.
develop a bacteria that could break down microsoft into smaller more benign compounds!
The genetically altered bacteria Deinococcus radiodurans does not consume radioactive compounds as the summary suggests. As physics assures us, it is [almost] impossible to alter the half-life of a radioactive compound or transmutate elements without massive equipment. OTOH, what these bacteria do is that they have been genetically customized to transform highly reactive heavy metal compounds into more tame and benign materials. The "radiodurans" part of the name refers to the fact that the bacteria can withstand "1.5 million rads of gamma radiation, or about 3,000 times the lethal dose for humans." Pretty amazing stuff.