FIG. 8.

Effects of ipeX overexpression on OmpC and PhoA synthesis from various plasmid constructs. ipeX was expressed from an IPTG-inducible promoter of pTrc99A. ompC was expressed from a 1.5-kb noncoding region of ompC which contains its native 248-bp promoter and UTR (gray box) (A). This ompC clone was present on a plasmid replicon (pSC101) compatible with the ColE1 replicon of pTrc99A. phoA clones were present on pACYC184, which is also compatible with pTrc99A. PhoA synthesis was placed under the control of the 248-bp ompC promoter and UTR sequences (gray box) (B and C). Filled and open arrows show mature protein-coding regions of ompC and phoA, respectively. phoA constructs used either ompC's (striped box) (B) or phoA's (open box) (C) signal sequence-coding region (ss). Plus and minus signs refer to cultures with or without the IPTG inducer, respectively. OmpC and PhoA proteins were visualized from whole cells by Western blot analyses with OmpC (A) and PhoA (B and C) antibodies.