Figure 4. rRNA operon deletion study.

(A) Analysis of the effect of rRNA operon deletion to the ribosome production capability of the network. As expected, the ribosome production rate decreased with decreasing number of available rRNA operons. All possible combinations of operon deletions were considered resulting in different maximal possible ribosome production rates for a given number of remaining rRNA operons. This is due the gene dosage effect since multiple replication forks are present at higher growth rates. (B) Experimental data (orange bars, [46],[48]) suggested much higher ribosome production than we determined in (A). This compensation is achieved by increasing the transcription rate of the remaining rRNA operon. We tested different possible compensation factors and compared the results with the experimental data. The error bars are again caused by different combination of rRNA operons.