Figure 6
From: Stationary phase expression of the arginine biosynthetic operon argCBH in Escherichia coli
RpoS dependent expression of argH in exponential and stationary phase determined by Northern analysis. RNA was extracted from cultures grown in LB to OD600 = 0.3 for exponential phase (E) and OD600 = 1.5 for stationary phase (S) using the hot phenol method (as described in Methods). 5 μg of RNA was loaded in each lane. Signal intensity was quantified by densitometry and normalized to an arbitrary value of 10 for expression of the operon in stationary phase in the wild type strain.