Essential Genetics 6th Edition by Daniel Hartl

Exercise 2

The leader sequence of the metI transcript involved in methionine biosynthesis in Bacillus subtilis acts as a riboswitch that binds S-adenosylmethionine (SAM) in a manner analogous to the yitJ leader RNA. What phenotype would be expected of cells with a mutation in metI in which the leader was unable to bind with SAM?