In E. coli, eight enzymatic steps are involved in the biosynthesis of arginine f
ID: 217394 • Letter: I
Question
In E. coli, eight enzymatic steps are involved in the biosynthesis of arginine from glutamate. The synthesis of the required enzymes is subject to control by the ArgD protein, which, on its own, binds weakly to a regulatory sequence just downstream of the promoter regions for these genes. Upon the addition of excess arginine to the growth medium, the respective mRNA molecules are no longer produced. What is the likely role of arginine in the control of these genes?
Choose one and give a brief explanation:
A. activator
B. repressor
C. operator
D. inducer
E. corepressor
Explanation / Answer
Arginine act as repressor in e.coli to control the genes this is the reason why mRNA is no longer produced.