Figure 2.

Transcription kinetics at different crowding conditions measured by the in vitro single-round quenched-kinetics transcription assay. (A) Simplified transcription model used for extraction of kinetic constants from the results of in vitro quenched-kinetics assays. (B) Transcription kinetics in the presence of 25% glycerol (black square), 15% PEG 8000 (wine pentagon), 5% Dextran500 (olive hexagon) and 15% Ficoll70 (blue diamond) compared to transcription kinetics in buffer (red circle). All transcription efficiencies were normalized to the reaction at 25 min without a crowder. (C) The relative viscosity-adjusted rate constants (compared to the rate constant without a crowder). In (B), error bars represent the standard deviation of triplicate repeats. Error bars in (C) were calculated based on microviscosities for crowders and standard errors obtained from the fitting procedure.