Bacteria digest toxic metals
Saturday, March 28th, 2009 at 5:59 amThis article from Discovery caught my eye this morning. Just like humans breathe in oxygen and breathe out carbon dioxide, “some bacteria take in toxic metals and release non-toxic versions.” Scientists have been trying to work out how, with the goal of using the bacteria to clean up nuclear waste sites. “A new study brings that goal one step closer to reality. Researchers have identified and located two proteins that give certain bacteria the power to detoxify dangerous metals, including uranium, chromium and technetium.”
Microbiologist Brian Lower, whose team made the discovery, also notes that the bacteria they studied, Shewanella oneidensis, “generate a small amount of electricity as they eat waste, giving them potential as biofuel cells”.
The bacteria aren’t ready to be put to work yet, however. “It’s a matter of outsmarting the microbes so they do what you want them to do rather than what they want to do,” said biologist Kenneth Nealson.
Hopefully, human beings can outsmart microbes. Which leads (sort of) to this: a lauded scientific thinker’s views on why climate change may not be such a bad thing. Freeman Dyson of Princeton’s Institute for Advanced Study has spoken out in favour of (scrubbed) coal and contends that carbon, and increased temperatures, might be helpful rather than harmful to life on the planet. I’m not qualified to have any opinion on Dyson’s views in those connections, but I found myself thinking about this one item in the article:
“(Dyson) had added the caveat that if carbon dioxide levels soared too high, they could be soothed by the mass cultivation of specially bred ‘carbon-eating trees,’ whereupon Eric Posner, a law professor at the University of Chicago, had looked through the thick grove of honorary degrees Mr. Dyson has been awarded — there are 21 from universities like Georgetown, Princeton and Oxford — and suggested that ‘perhaps trees can also be designed so that they can give directions to lost hikers.’ ”
To which my mind went, “Well, you know, why not?” Perhaps I’m just an optimistic fantasiser, but human beings have proven time and again just what clever monkeys we are. If it’s at all physically possible, it seems, we will find a way to do it. Given what nature has already done with organic material, the engineerability of biological matter seems a field full of opportunity, as Dyson believes:
“Biotech, he writes in his book, ‘Infinite in All Directions’ (1988), ‘offers us the chance to imitate nature’s speed and flexibility,’ and he imagines the furniture and art that people will ‘grow’ for themselves, the pet dinosaurs they will ‘grow’ for their children (he has six children himself), along with an idiosyncratic menagerie of genetically engineered cousins of the carbon-eating tree: termites to consume derelict automobiles, a potato capable of flourishing on the dry red surfaces of Mars, a collision-avoiding car.”
Because it’s human nature to look out for number one and to care about the short term more than the long term, I admit I’m pessimistic about the chances of the global push to reduce carbon emissions (and let’s assume these emissions are a bad thing). I can’t see any reason to place hope in the operation of selflessness and long-term thinking in (the perhaps mis-named) Homo sapiens. As I see it, the only spot to park a bit of hope is in our orangutan-like cleverness with technology. Rather than expect us to become any wiser that we’ve shown ourselves capable of being since we climbed down from the trees, I’m hoping we’ll somehow MacGyver our way out of trouble. And grow those My Little Dinosaurs. And collision-avoiding potatoes.
March 28th, 2009 at 1:08 pm
This reminded me of an article I read in ‘Australasian Scientist’, which made a brief reference to Deinococcus radiodurans, which has been nicknamed ‘Conan the Bacterium’ given that it appears to be all but indestructible.
It is the height of human conceit to regard ourselves as being at the pinnacle of evolution. We can die if we stay out in the sun too long, or go a measly three days without water. So called ‘primitive’ organisms like Conan the Bacterium or any species of Tardigrades (Water Bear) can survive thousands of times the radiation that would kill a weak, pathetic human, let alone mere dehydration or a little UV light. Hell, they’ve even survived space!
Ultimately, the conservation effort is not about saving the planet, it’s about our own survival even though many people don’t see it this way and indeed, can make well-meaning but serious mistakes. I remember reading about the California condor conservation programme some time ago. When the 22 birds that formed the conservation programme were captured from the wild, they were each treated for parasites. The mite that dropped from their feathers has never been recorded in another living species, before or since. In order to save the Californian condor another species was exterminated and no one gave it a second thought. It was only a mite after all.
March 28th, 2009 at 8:19 pm
I adore Water Bears. I’d like a big plushy one =). I almost agree that saving the planet is about our own survival. I mean, it is, basically, but it’s also obviously about our mental wellbeing. We might be able to survive in bunkers in a barren wasteland, but how happy would we be without greenery and wildlife for us to enjoy and be inspired by? (Let’s hope that uninspiring mite didn’t hold the cure to cancer in its genome.)
In the very long term, though, it might be about more than us. If we were to allow, say, orangutans to go extinct, we’d be cutting off a potential avenue for the evolution of consciousness, which would be a pity (if the idea of the extinction of consciousness in the world gives you a horrid feeling, anyway).