Systematic perturbation of cytoskeletal function reveals a linear scaling relationship between cell geometry and fitness.
Cell Rep
; 9(4): 1528-37, 2014 Nov 20.
Article
in En
| MEDLINE
| ID: mdl-25456141
Diversification of cell size is hypothesized to have occurred through a process of evolutionary optimization, but direct demonstrations of causal relationships between cell geometry and fitness are lacking. Here, we identify a mutation from a laboratory-evolved bacterium that dramatically increases cell size through cytoskeletal perturbation and confers a large fitness advantage. We engineer a library of cytoskeletal mutants of different sizes and show that fitness scales linearly with respect to cell size over a wide physiological range. Quantification of the growth rates of single cells during the exit from stationary phase reveals that transitions between "feast-or-famine" growth regimes are a key determinant of cell-size-dependent fitness effects. We also uncover environments that suppress the fitness advantage of larger cells, indicating that cell-size-dependent fitness effects are subject to both biophysical and metabolic constraints. Together, our results highlight laboratory-based evolution as a powerful framework for studying the quantitative relationships between morphology and fitness.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Cytoskeleton
/
Escherichia coli
/
Genetic Fitness
Language:
En
Journal:
Cell Rep
Year:
2014
Document type:
Article
Country of publication: