Fe-S cluster metabolism regulates biofilm formation through the IscR metalloregulatory protein in E. coli

 

F. Wayne Outten

Department of Chemistry and Biochemistry, University of South Carolina

 

 

Biofilm formation is a complex developmental process regulated by multiple environmental signals.  In addition to other nutrients, the transition metal iron can also regulate biofilm formation.  Iron-dependent regulation of biofilm formation varies by bacterial species and the exact regulatory pathways that control iron-dependent biofilm formation are often unknown or only partially characterized.  We recently examined the role of iron availability in regulating biofilm formation in E. coli[1].  Our studies indicate that biofilm formation is repressed under low iron conditions in E. coli.  Furthermore, a key iron regulator, IscR, controls biofilm formation in response to changes in cellular Fe-S homeostasis1.  When Fe-S cluster assembly is disrupted, IscR activates the FimE recombinase to switch off expression of Type I fimbrae in E. coli1,[2].  Iron-dependent regulation of FimE via IscR leads to decreased surface attachment and biofilm dispersal under iron-limiting conditions.

 



[1] Wu, Y.; Outten, F.W. J Bacteriol, 2009, 191, 1248-1257

[2] Giel, J.L.; Rodionov, D.; Liu, M.; Blattner, F.R.; Kiley, P.J. Mol Microbiol. 2006, 60, 1058-1075