Microbiology. In the article “DNA strand separation during activation of a developmental promoter by the Bacillus subtilis response regulator Spo0A” by Dean A. Rowe-Magnus and George B. Spiegelman, which appeared in number 9, April 28, 1998, of Proc. Natl. Acad. Sci. USA (95, 5305–5310), the following correction should be noted. In Fig. 2, the DNA sequences shown for MB8NT and MB8T templates are incorrect. The sequence of the bottom strand of the MB8NT template should be 3′-AACGAATATACTTAACTTCGTTCTTC-5′, and the sequence of the top strand of the MB8T template should be 5′-TTGCTTATATGAATTGAAGCAAGAAG-3′ (the sequences that are incorrect in the figure are underlined).