All 23 <i>Ca.</i> Pelagibacter ubique mRNA transcripts that were at least 50 percent more abundant in the iron-limited cultures compared to the control cultures, 24 hours after addition of an iron-chelator.

Seventy-eight percent of these genes are found in Figure 2's early and late iron stress clusters. Bullet points in the first column indicate contiguous loci. aAverage fluorescence of three replicates, (iron limited culture/iron replete culture). bResult of a two-tailed Student's t-test comparing the three biological replicates for each treatment.