First of, I remember various faiths teaching about faith as a seed that
grows. So, its a question that stalked people, maybe since forever. For
all we know, the starting seed of alien life form could be as small as
the last seen small thing that exibited properties of life. It would
have enough energy to alter the smallest portion of enviroment around
it. Yet again, from there it would be one cool green thing to watch.
DNA is a low calory food. It mostly contains information, and a
necessary paradox because your question still makes sense entirely.