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The Lactose Operon of Escherichia coli

  • Richard E. Sanders

Abstract

The two enzymes which are specific for the catabolism of the disaccharide lactose in Escherichia coli are the lactose permease and beta galactosidase (Watson, 1970). The structural genes for these molecules are regulated as a unit and located adjacent to one another on the coli chromosome (see Figure 1). The Y gene codes for the permease or M protein which transports lactose into the cell. The Z gene carries the information for the synthesis of beta-galactosidase. This enzyme cleaves lactose to glucose and galactose, both of which can directly enter glycolysis and supply the cell with energy and carbon skeletons (Watson, 1970; Zabin and Fowler, 1970; Kennedy, 1970). (The a gene codes for thiogalactoside transacetylase. The role of this enzyme in E. coli is unknown.)

Keywords

Cold Spring Harbor Cold Spring Harbor Laboratory Beta Galactosidase Lactose Permease Lactose Operon 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1974

Authors and Affiliations

  • Richard E. Sanders
    • 1
  1. 1.Department of BiologyMassachusetts Institute of TechnologyCambridgeUSA

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