L-box
The L-box is a riboswitch that binds lysine and controls gene expression by a termination/ antitermination mechanism. Upon binding of lysine, the L-box adopts a terminator structure thtus preventing expression of lysC. In the absence of lysine, the L-box has an antiterminator structure that allows lysC expression and thus lysine biosynthesis.
Gene controlled by a L-box mechanism
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