Module 2: Aggregation

Description | Design | Construction | Characterisation | Shear Device | Modelling | Results | Conclusions

Characterisation

The characterisation of curli expression will be done via a Congo Red agar assay. Congo Red is a diazo dye that causes cells expressing curlis to be stained red (Barnhart et al. 2006). Hence, Congo Red agar provides a convenient assay to determine if the expression of curlis has been successful.

Besides the expression of curlis, we also want to ascertain the shear resistance of the biofilm formed by the curliated cells. As such, we will also be analysing this by determining the critical shear forces involved in the attachment and detachment of cells from plastic surfaces. We will be doing this by creating an analogue of a LH Fowler Cell Adhesion Measurement Module, which creates a variable shear gradient across the surface of the biofilm, thereby allowing us to ascertain the critical shear stresses at which our cells adhere and detach from the plastic surfaces (Webb et al. 1986).