FIG. 5.

RpoS does not affect the amount of Pol IV in strains overexpressing Pol IV from an exogenous promoter. (A) Western blot of total cell protein probed with anti-Pol IV antibody. For each pair of strains, the indicated amounts of protein were loaded onto the polyacrylamide gel. The strains overexpressing Pol IV were harvested in the exponential phase (see Materials and Methods), whereas the three control strains on the right were harvested in the stationary phase. (B) Quantification of the bands in A for the strains overexpressing Pol IV. The lighter bars correspond to the rpoS::Cm mutant strain, and the darker bars represent the wild-type strain. Wild type, FC722; PFG419, rpoS::Cm; wild type/pdinB⁺⁺, PFG266; rpoS::Cm/pdinB⁺⁺, PFG420.