Nat. Biotechnol. 28, 42 (2010); published online 8 January 2010; corrected after print 5 February 2010

In the version of this article initially published, the organisms in question were incorrectly identified as Mycobacterium pneumoniae and Mycobacterium genitalium. The correct names are Mycoplasma pneumoniae and Mycoplasma genitalium, respectively. The error has been corrected in the HTML and PDF versions of the article.