FIG. 2.

Linearity of the v-PCR method and viable cell discrimination in mixed samples. PCR values obtained from viable (A) or heat-killed (B) serially diluted suspensions treated with EMA were compared with those obtained from untreated suspensions to analyze the influence of the total amount of Legionella cells on the v-PCR results. Error bars represent standard deviations from three independent replicates. Logs of GU values determined by v-PCR are shown as a function of the proportion of viable (C) or dead (D) L. pneumophila cells present in mixtures of defined ratios of viable and dead cells.