Correction

MICROBIOLOGY. For the article “Isolation of peptide aptamers that inhibit intracellular processes” by Jonathan H. Blum, Simon L. Dove, Ann Hochschild, and John J. Mekalanos, which appeared in number 5, February 29, 2000, of Proc. Natl. Acad. Sci. USA (97, 2241–2246; First Published February 25, 2000; 10.1073/pnas.040573397), the authors note that the following citation should appear where work is cited on the use of peptide aptamers to inhibit signaling pathways in yeast: Geyer, C. R., Colman-Lerner, A. & Brent, R. (1999) Proc. Natl. Acad. Sci. USA 96, 8567–8572.