Nature 522, 315–320 (2015); doi:10.1038/nature14451

In this Article, Torsten Luksch was inadvertently omitted from the author list. He is affiliated with the Drug Discovery Unit, Division of Biological Chemistry and Drug Discovery, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK. His contribution was the analysis of initial screening data alongside author A.W. The online versions of the paper have been corrected.