Correction

APPLIED BIOLOGICAL SCIENCES. For the article “Phylogenetic and biochemical evidence for sterol synthesis in the bacterium Gemmata obscuriglobus,” by Ann Pearson, Meytal Budin, and Jochen J. Brocks, which appeared in issue 26, December 23, 2003, of Proc. Natl. Acad. Sci. USA (100, 15352-15357; first published December 5, 2003; 10.1073/pnas.2536559100), the authors note that the following statement should be added to the acknowledgements: “Preliminary sequence data were obtained from The Institute for Genomic Research web site at www.tigr.org. Sequencing of Gemmata obscuriglobus was accomplished with support from the U.S. Department of Energy.”