<p>The red lines represent the last simulated step. a) The time evolution for a single molecule. We consider that the movement is uniform between each step. The velocity is assigned by the Gillespie algorithm. b) The method used to solve collisions. In blue we show the leader RNAP and in black the trailing RNAP. represents the required time for the collision. is the time for the first event among the following possibilities: nucleotide inclusion by trailing RNAP, nucleotide inclusion by leading RNAP or collision.</p
