That is one amazing bug. That way of building chromosomes sounds like one of those rare cases when evolution actually does have a direction--a mutation that confers extra resistance to mutation would tend to be a one-way street.

It sounds to me like taking advantage of radiodurans involves more than local gene splicing to introduce a specific trait. What it does sounds more like a fundamentally new way of organizing a cell, a change in "design philosophy" like eukaryotic life, if not quite so radical in scope. Toroidal DNA...what will Ma Nature think of next?

As attractive as the benefits would seem to be, I might be inclined to hold off on this one until we've worked out more pedestrian and local genetic engineering reliably. This is messin' with a fundamental. Be careful, Dr. Frankenstein.

I agree. Such a massive redesign of the genome of a higher organism is probably at least a century away. But Deinococcus radiodurans does have other features that could be borrowed.

D. radiodurans also possess carotenoid pigments, oxygen toxicity defense enzymes, and a distinctive outer membrane. First, carotenoids, which cause red pigmentation, are thought to act as free radical scavengers, thus increasing resistance to DNA damage by hydroxyl radicals. Next, high levels of enzymes such as superoxide dismutase and catalase both play a role in effective defense mechanisms against oxygen toxicity. Finally, a cell wall forming three or more layers with complex outer membrane lipids and a thick peptidoglycan layer containing the amino acid omithine also serves to protect D. radiodurans from lethal doses of radiation.

These defenses seem to be in the realm of possibility for making the leap from single prokaryotic cells to more advanced eukaryotic cells. Trying to copy the DNA structure of the superbug for Human consumption is a whole other ball game. Such an arrangement may work fine for simple plasmids, but trying to fit a massive multi-chromosome double helix into such a shape would be problematic at best.