Inducible operons

Stansen C, Uy D, Delaunay S et al (2005) Characterization of a Corynebacterium glutamicum lactate utilization operon induced during temperature-triggered glutamate production. Appl Environ Microbiol 71 5920-5928... 

More than 30 years ago Jacob and Monod introduced the Escherichia coli lac operon as a model for gene regulation. The lac repressor molecule functions as a switch, regulated by inducer molecules, which controls the synthesis of enzymes necessary for E. coli to use lactose as an energy source. In the absence of lactose the repressor binds tightly to the operator DNA preventing the synthesis of these enzymes. Conversely when lactose is present, the repressor dissociates from the operator, allowing transcription of the operon. 

Lewis, M., et al. Crystal structure of the lactose operon repressor and its complexes with DNA and inducer. Science 271 1247-1254, 1996. 

It transpires that the heat shock genes of one single bacterial species are regulated by different mechanisms. Genes and operons controlled by one particular regulator are called regulons and, if there are at least two regulons in one species induced by the same stress factor, they form a stimulon. 

Revelles O, M Espinosa-Urgel, S Molin, JL Ramos (2004) The davDT operon of Pseudomonas putida, involved in lysine catabolism, is induced in response to the pathway intermediate 5-aminovaleric acid. J Bacterial 186 3439-3446. 

Herrera, G., Urios, A., Alexandre, V, and Blanco, M., (1988). UV light induced mutability in Salmonella strains containing the limit DC or the mite AB operon evidence for a limit C function. Mutation Res. 198 9-13. 

Rey L, MuriUo J, Hernando Y, et al. 1993. Molecular analysis of a microaerobically induced operon required for hydrogenase synthesis in Rhizobium leguminosarum biovar vicae. Mol Microbiol 8 471-81. 

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