Nat. Biotechnol. 32, 1197–1198 (2014); published online 9 December 2014; corrected after print 29 April 2015

In the version of this article initially published, in two instances molecules were misidentified in the text. The last sentence in the legend of Figure 1 should have read, “a charged phosphodiester,” rather than “a phosphatediester.” On p.1197, third column, first paragraph, “intracellular phosphodiesterases....” should have read, “intracellular thioesterases....” The errors have been corrected in the HTML and PDF versions of the article.