Table 7-2Sigma Factors of E. coli

σ70 most genes
σ32 genes induced by heat shock
σ28 genes for stationary phase and stress response
σ28 genes involved in motility and chemotaxis
σ54 genes for nitrogen metabolism

The sigma factor designations refer to their approximate molecular weights, in kilodaltons.

From: How Genetic Switches Work

Cover of Molecular Biology of the Cell
Molecular Biology of the Cell. 4th edition.
Alberts B, Johnson A, Lewis J, et al.
New York: Garland Science; 2002.
Copyright © 2002, Bruce Alberts, Alexander Johnson, Julian Lewis, Martin Raff, Keith Roberts, and Peter Walter; Copyright © 1983, 1989, 1994, Bruce Alberts, Dennis Bray, Julian Lewis, Martin Raff, Keith Roberts, and James D. Watson .

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