1. Acknowledgements Abbreviations
We would like to thank Dr. Julian Gough for providing us the SCOP structural domain assignments from SUPERFAMILY, Dr. Collado-Vides and Dr. Salgado Heladia for providing us information from RegulonDB.
M. Madan Babu is an LMB Cambridge fellow and is supported by the Cambridge Overseas Trust, Cambridge Commonwealth Trust and Trinity External Research Studentship.
Abbreviations
DBD: DNA Binding Domain; TF: Transcription Factor; A: Activator; R: Repressor;
D: Dual Regulator; U: Unknown regulatory function; RNAP: RNA Polymerase

2. Publications
M. Madan Babu* and Sarah. A. Teichmann (2003). Functional Determinants of Transcription Factors in E. coli: Protein Families and Binding Sites, Trends in Genetics, 19:75-79.
M. Madan Babu* and Sarah. A. Teichmann (2003). Evolution of Transcription Factors and the Gene Regulatory Network in E. coli, Nucleic Acids Research, 31:
Sarah. A. Teichmann* and M. Madan Babu*. Evolution of Gene Regulatory Network by Duplication, manuscript in preparation.

3. Evolution of Transcription Factors and the Gene Regulatory Network in E. coli
M. Madan Babu and Sarah A. Teichmann ::
MRC Laboratory of Molecular Biology Hills Road, Cambridge CB2 2QH, UK