[6] Genetic approaches to study of biofilms

This chapter focuses on the description of rapid and reliable assays for isolating mutants that are unable to form a biofilm on an abiotic surface. It also discusses additional methods that are useful for efficiently classifying and characterizing these mutants. The genetic approach described in this chapter has the potential to expand the understanding of biofilm development profoundly. The methods outlined are simple and can be applied readily to study many different types of bacteria that inhabit surface-associated communities. Subsequent microscopic and molecular analyses of the mutants uncovered by these screens are also straightforward. The results of these screens for mutants defective in biofilm formation in P. aeruginosa, P. fluorescens, E. coli, V.cholera, S. putrefaciens, and S. epiderrnidis have identified genes of both known and unknown function. A molecular understanding of the control of biofilm development may eventually be applied to limit both the virulence and the distribution of pathogens in various environments, serve as a means to regulate microbial attachment to and degradation of solid materials, and improve the control of biofilm formation in industrial settings.