Sciencemadness Discussion Board

Acquired resistence of bacteria to UV

saps - 20-7-2005 at 13:48

could bacteria mutate, making them resistant to uv-c light.

E.b.C: Title

[Edited on 21-7-2005 by chemoleo]

Blind Angel - 20-7-2005 at 14:57

I don't think so, though I can't explain, maybe because it attack directly the membrane. But since UV is one of the most widely used desinfection mean, it would surprise me greatly if one bacteria would mutate to resist to UV, and if it could, it would have done since a long time since it's so used.

chemoleo - 20-7-2005 at 16:32

Indeed, it is just as BlindAngel says. If you gave it thousands of years, at high UV, I am sure some would mutate to survive. But don't hold your breath, it won't happen over night.
Plus, in nature, high UV conditions arent really that common, except high up in the mountains or recently in Antarctica/NZ/south Australia.
It will be interesting to see if new variants arise. Give it time, and probably they will.

BTW - conferring resistance to UV is not a simple matter, unlike i.e. an antibiotic. UV acts on DNA and proteins alike, non-specifically, the very components that make up a functioning cell.
Covalent changes of proteins/DNA cant be easily repaired unless several sets of genomes are present, and indeed, there is ONE KNOWN type of bacterium that is highly radiation resistant, Deinococcus Radiodurans. See an abstract on its genome here. I once gave a talk about it, but I cant find it (I think it got lost in my computer crash), if I do (one day), I will post it.

Mr. Wizard - 20-7-2005 at 17:49

Yes they could mutate. If cockroaches and other organisms can withstand hard ionizing radiation, I'm sure , given time, a bacterial strain could adapt to UV. Some of the possibilities might include heavy pigmentation to protect vulnerable parts, heavy redundancy of critical DNA and enzymes, with damage repair. A very active free radical scavenging would help too. With the right 'blueprints', the UV could even be used as an energy source. A very fast breading rate would also be good, as it would allow the DNA to be duplicated before it was damaged. This is all speculation on my part, but why not?