lac operon(redirected from Lac A)
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a collection of adjacent bacterial genes responsible for the entry and metabolism of lactose; contains the genes coding for three enzymes and is flanked by a repressor and a promoter region to control expression.
Farlex Partner Medical Dictionary © Farlex 2012
lac operonA sequence of genes found in many bacteria that codes for the enzymes needed to break down lactose to glucose and galactose so that the sugars can be utilized. Studies on the lac operon have been important in genetic research. The lactose repressor protein controls the transcription of the lac operon.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005
lac operonthe genetic system of Escherichia coli that is required to metabolize lactose and on which the OPERON MODEL is based.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005