Nat. Chem. Biol. 6, 82–83 (2010); published online 15 January 2010; corrected after print 2 March 2010

In the version of this article initially published, there was an error in the chemical structure of IC87114 that arose from the coordinates used to generate Figure 1a. The corrected structure has been deposited by Berndt et al. to the Protein Data Bank (PDB code 2X38). Figure 1a and the PDB code in the figure legend have been corrected in the HTML and PDF versions of the article.