title: Cell-Size Homeostasis and the Incremental Rule in a Bacterial Pathogen.
abstract: How populations of growing cells achieve cell-size homeostasis remains a major question in cell biology. Recent studies in rod-shaped bacteria support the "incremental rule" where each cell adds a constant length before dividing. Although this rule explains narrow cell-size distributions, its mechanism is still unknown. We show that the opportunistic pathogen Pseudomonas aeruginosa obeys the incremental rule to achieve cell-length homeostasis during exponential growth but shortens its cells when entering the stationary phase. We identify a mutant, called frik, which has increased antibiotic sensitivity, cells that are on average longer, and a fraction of filamentous cells longer than 10 μm. When growth slows due to entry in stationary phase, the distribution of frik cell sizes decreases and approaches wild-type length distribution. The rare filamentous cells have abnormally large nucleoids, suggesting that a deficiency in DNA segregation prevents cell division without slowing the exponential elongation rate.
authors.affiliation: Program in Computational Biology, Memorial Sloan-Kettering Cancer Center, New York, New York.
authors.forename: Maxime
authors.initials: M
authors.lastname: Deforet
authors.affiliation: Program in Computational Biology, Memorial Sloan-Kettering Cancer Center, New York, New York.
authors.forename: Dave
authors.initials: D
authors.lastname: van Ditmarsch
authors.affiliation: Program in Computational Biology, Memorial Sloan-Kettering Cancer Center, New York, New York. Electronic address: xavierj@mskcc.org.
authors.forename: João B
authors.initials: JB
authors.lastname: Xavier
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002453:Cell Cycle; D006706:Homeostasis; D009154:Mutation; D011550:Pseudomonas aeruginosa / Q000166:cytology* / Q000187:drug effects / Q000235:genetics / Q000502:physiology
chemical_list: D000900:Anti-Bacterial Agents