Temporal evolution of protein levels subject to intrinsic noise.

<p>Output from system (1)–(6) computed using the Gillespie SSA. Histograms show the levels of (A) DegU and (B) exoprotease collated from 1000 simulations at 10 time points. Each simulation can be considered to be equivalent to the temporal evolution of transcription in a single cell. Note that distributions for both DegU and exoprotease display no significant further change after approximately hrs. All parameter values from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0038574#pone-0038574-t001" target="_blank">Table 1</a> except . Initial protein values set to zero.