Microbes discovered that can digest plastics at low temperatures

For past two decades, this news shows up every year as if some new ground breaking discovery is made. We have seen no impact of any kind so far. It seems some research group releases this to media whenever they are due to apply for funding.

I'm curious to what is the output from the digestion - apart from more microbes.

This is the start of a sci-fi book I read many years ago, but I can't remember the name of it.