alt Hacker NewsMaybe it's the very molecules that the live cells were using, just doing their thing without the cells. Cells concentrate things by confining them in a small volume, but otoh, if you have damp particles, the thin water layer on the particles would be a kind of confining space, with the added advantage of surface area to exchange gases with.
This is addressed later in the article. They think there's probably some of that activity but don't think those molecules could last long enough to produce the observed effect.