Regulation of the L-arabinose operon in Escherichia coli
نویسنده
چکیده
GENERAL BACKGROUND Escherichia coli can grow on L-arabinose as a source of carbon and energy (Fig. 1) (Schleif, 1996). Not surprisingly, because the amounts of enzymes required to convert arabinose into a component of the pentose phosphate shunt are significant, the levels of the enzymes are regulated. In the absence of arabinose, the uninduced or basal level of expression of the proteins is about 1/300 the induced level. It is a product of one of the genes of the arabinose operon, the AraC protein, that controls the expression level and hence is a sensor of the presence of arabinose. AraC protein transduces information about the sugar’s presence into an induced synthesis rate of the AraE, AraF and AraG proteins, which are required for arabinose uptake, as well as the AraB, AraA and AraD enzymes, which are required for the catabolism of arabinose.
منابع مشابه
L-arabinose operon of Escherichia coli
TIG December 2000, volume 16, No. 12 559 Over forty years of research on the L-arabinose operon of Escherichia coli have provided insights into the mechanism of positive regulation of gene activity. This research also discovered DNA looping and the mechanism by which the regulatory protein changes its DNA-binding properties in response to the presence of arabinose. As is frequently seen in focu...
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