EcoCyc: a comprehensive database of Escherichia coli biology.
Keseler IM, Collado-Vides J, Santos-Zavaleta A, Peralta-Gil M, Gama-Castro S, Muñiz-Rascado L, Bonavides-Martinez C, Paley S, Krummenacker M, Altman T, et al. Nucleic Acids Res. 2011 Jan; 39(Database issue):D583-90. Epub 2010 Nov 21.