FIG. 6.
Expression of pcaU in E. coli. Denaturing sodium dodecyl sulfate-gel (12.5% [wt/vol] acrylamide) electrophoresis of crude extracts (100 μg of protein per lane) of E. coli DH5α strains containing the following: lanes 1 and 6, molecular weight standards; lane 2, the unmodified vector pWH661+; lane 3, pZR18 containing pcaU oriented so that its transcription is not under the control of lacP; lane 4, pZR22 containing pcaU oriented so that its transcription is initiated by lacP; lane 5, pZR26 (pZR22 modified by insertion of a lacZ-Knr cassette into pcaU).