FIG 6.

Mutation of cysE results in decreased transcription of phospholipase and flagellar genes. cDNA prepared from S. marcescens strains cultured in M9 plus CA was used to assess relative levels of phospholipase and flagellar gene transcripts (x axis) by qRT-PCR. Transcript levels for the cysE mutant harboring an empty vector (cysE/vector) and the complemented cysE mutant (cysE⁺) are shown as fold decrease relative to that of the wild-type strain. The dotted line at 1.0 on the y axis indicates a hypothetical value at which there is no change relative to the wild-type strain. Bars represent the means (±standard deviations) from three independent experiments, and asterisks denote significant differences in relative levels between the cysE mutant and complemented cysE mutant strains (t test). *, P < 0.05; **, P < 0.01).