Involvement of FtsZ protein in shift-up-induced division delay in Escherichia coli.
A nutritional shift-up from glucose minimal medium to LB broth was previously shown to cause a division delay of about 20 min in synchronized cultures of Escherichia coli, and a similar delay was observed after a nutritional pulse (a shift-up followed rapidly by a return to glucose minimal medium). Using synchronized cultures, we show here that the pulse-induced division delay does not require protein synthesis during the period in LB broth, suggesting that a nonprotein signal is generated by the shift-up and transmitted to the cell division machinery. The cell division protein FtsZ, target of the SOS-associated division inhibitor SfiA (or SulA), seems to be involved in the postshift division delay. Mutants in which the FtsZ-SfiA interaction is reduced, either sfiA (loss of SfiA) or ftsZ(SfiB) (modification of FtsZ), have a 50- to 60-min division delay after a shift-up. Furthermore, after a nutritional pulse, the ftsZ(SfiB) mutant had only a 10- to 16-min delay. These results suggest that the FtsZ protein is the target element of the cell division machinery to which the shift-up signal is transmitted.
D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D002455:Cell Division; D003470:Culture Media; D004261:DNA Replication; D004926:Escherichia coli / Q000166:cytology* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D009154:Mutation
D001426:Bacterial Proteins; D003470:Culture Media