Fig. 1

Logical-continuous modelling pipeline for bistability analysis of curli regulation in E. coli. a Expression of the curli gene csgB in mutants with single or multiple knockout mutations in YegE/YhjH and YdaM/YciR c-di-GMP control modules (as indicated). Derivatives of E. coli K-12 W3110 carrying a single copy csgB::lacZ reporter fusion were grown in LB at 28 °C for 24 hours and β-galactosidase activities were determined. Figure reproduced from [7] with permission. b Signalling network regulating the expression of curli fibers, as suggested in [7]. c Logical formulation of the network topology. The two different functional states of YciR are modelled by two types of interactions. Only the inhibitory effects exerted by YciR are represented by edges in the figure. Full details on the regulatory activity of YciR and the dependence of the two functional states on the activity of c-di-GMP is formalised in the Additional file 1: Figure S1c. d Continuous model combining kinetic reaction rates with the validated network topology