First I want to know how many metgenomes in MG RAST database contain a specific organism I'm studying, say Roseobacter of Proteobacteria. Second, I need to download all these metagenomes to my local computer with a further try to assemble partial genomes of the target organism from each metagenome. My question is how to get these metagenome that contain target organisms out of the huge MG RAST database in a simple quick way. Any idea using MG RAST api? I got stuck here... eager to solve it...