Surface hygiene monitored using a reporter of fis in Escherichia coli


Goulsbra DP4-7, Unilever Research Port Sunlight, Quarry Road East, Bebington, Wirral CH63 3JW, UK (e-mail:


Aims: To examine the value of the fis promoter in monitoring regrowth of a surface-attached bacterial population following exposure to chemical stress using several candidate reporters, β-galactosidase (lacZYA), bacterial luciferase (luxAB) and enhanced green fluorescent protein (EGFP).

Methods and Results: The pattern of expression for the reporters within Escherichia coli cells attached to surfaces was determined. Both the bacterial luciferase reporter and EGFP were readily detected, but EGFP was found to overcome problems associated with luciferase and β-galactosidase. The effect of surface pretreatment, using polymer systems, on bacterial attachment and growth confirmed the usefulness of this approach.

Conclusions: The fis promoter, combined with EGFP, can be used successfully to study adhesion, biocidal damage and recovery. The stability of the EGFP enabled the magnitude of the total recovery response to be monitored as cells remained fluorescent after the decline in fis expression.

Significance and Impact of the Study: The E. coli Pfis-egfp reporter system provides a new, versatile and sensitive tool to investigate bacterial adhesion both quantitatively and qualitatively.