Skip to main content
. 2002 Oct;184(20):5781–5788. doi: 10.1128/JB.184.20.5781-5788.2002

FIG. 4.

FIG. 4.

Northern analysis and β-galactosidase assays show that traJ and FinP transcripts are expressed in both wild-type and cpxA101* E. coli. (A) Relative levels of traJ mRNA and FinP antisense RNA expressed from pOX38-Km in various backgrounds. Lanes 1 and 2, E. coli MC4100 without (−) or with (+) pOX38-Km; lanes 2 to 4, pOX38-Km in cpxA101* (TR189), cpxR (TR51), and cpxA (TR8) strains. The positions of the traJ transcript and FinP antisense RNA are indicated on the right. (B) Northern analysis to show a direct comparison of traJ mRNA levels in wild-type and cpxA101* backgrounds. Lanes 1 and 2, MC4100 without (−) and with (+) pOX38-Km; lanes 3 and 4, cpxA101* (TR189) without (−) and with (+) pOX38-Km. The position of the traJ transcript and the loading control, tRNASer, are shown on the right. (C) PtraJ activity is reduced in several cpx mutants. β-Galactosidase assays of MC4100 (lane 1), cpxA (lane 2), cpxR (lane 3), and cpxA101* (lane 4) carrying the PtraJ-lacZ reporter plasmid pMCJ211 were performed. Assays with the parental control plasmid resulted in insignificant levels of β-galactosidase activity and are not included.