Radioactive life
Hi Jeff
Their energy source would be a tricky thing indeed to depend on.
There was a lot of natural radioactivity in Earth's early days, much more than today thanks to decay, so there may well be origin of life issues in this find's implications. But these days the supply of radioactive elements is very patchy, mostly due to intrusive igneous rock like granites. Perhaps the bugs had to secondarily adapt which is a pretty cool example of micro-life's tenacity.
Metazoic life - not so easy to keep us going.
Adam