title: E. coli filament formation induced by heterologous S-layer expression.
abstract: Escherichia coli is a rod-shaped intestinal bacterium which has a size of 1.1-1.5 µm x 2.0-6.0 µm. The fast cell division process and the uncomplicated living conditions have turned E. coli into a widely used host in genetic engineering and into one of the best studied microorganisms of all. We used E. coli BL21(DE3) as host for heterologous expression of S-layer proteins of Lysinibacillus sphaericus JG-A12 in order to enable a fast and high efficient protein production. The S-layer expression induced in E. coli an unusual elongation of the cells, thus producing filaments of > 100 µm in length. In the stationary growth phase, E. coli filaments develop tube-like structures that contain E. coli single cells. Fluorescence microscopic analyses of S-layer expressing E. coli cells that were stained with membrane stain FM (®) 5-95 verify the membrane origin of the tubes. Analyses of DAPI stained GFP-S-layer expressing E. coli support the assumption of a disordered cell division that is induced by the huge amount of recombinant S-layer proteins. However, the underlying mechanism is still not characterized in detail. These results describe the occurrence of a novel stable cell form of E. coli as a result of a disordered cell division process.
authors.affiliation: Institute of Radiochemistry, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.
authors.forename: Franziska L
authors.initials: FL
authors.lastname: Lederer
authors.forename: Tobias J
authors.initials: TJ
authors.lastname: Günther
authors.forename: Johannes
authors.initials: J
authors.lastname: Raff
authors.forename: Katrin
authors.initials: K
authors.lastname: Pollmann
mesh_terms: D001406:Bacillaceae / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics* / Q000254:growth & development* / Q000378:metabolism; D010861:Fimbriae, Bacterial / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D008562:Membrane Glycoproteins; C055764:S-layer proteins