That's one non-biologist's initial guess, by no means a tested theory, and certainly not backed by enough evidence yet to say "probably". Seems much more likely that it's a case of contamination - this plankton lives in the belly of shrimps and other seafood. Shrimp are one of the ISS astronauts' favorite foods. All it takes is one astronaut not washing his hands after eating and before putting on his gloves to cause contamination. If the bacteria are alive, this is definitely the basis for an interesting study re: extremophiles. But the "uplifting air currents" statement is just speculation at this point.