Found the article. (or at least it seems to be, given it studies “60 samples of belly buttons” and finds “2368 phylotypes of bacteria”. I don’t see anything in this study about “1458 bacteria completely new to science” or anything about the Japanese soil thing. It’s entirely possible I’m looking at the wrong study, but generally, it’s a safe assumption that the source for memes like this is a half-remembered telephone game at best.