Streptomyces were long thought to be prominent contributors at work in breaking down cellulose, and to be equally active in the cause across hundreds or thousands of strains of the bacteria.
The UW–Madison researchers measured the relative abilities of more than 200 types of Streptomyces bacteria by growing them on simple sugar and on a good source of cellulose: filter paper (which is made of dead trees).
They were able to collect the genomes of more than 120 of those strains, and identify the genes — and the ways key genes were expressed — that set strong cellulose degraders apart from poor ones.