Bistability, epigenetics, and bet-hedging in bacteria.
Clonal populations of microbial cells often show a high degree of phenotypic variability under homogeneous conditions. Stochastic fluctuations in the cellular components that determine cellular states can cause two distinct subpopulations, a property called bistability. Phenotypic heterogeneity can be readily obtained by interlinking multiple gene regulatory pathways, effectively resulting in a genetic logic-AND gate. Although switching between states can occur within the cells' lifetime, cells can also pass their cellular state over to the next generation by a mechanism known as epigenetic inheritance and thus perpetuate the phenotypic state. Importantly, heterogeneous populations can demonstrate increased fitness compared with homogeneous populations. This suggests that microbial cells employ bet-hedging strategies to maximize survival. Here, we discuss the possible roles of interlinked bistable networks, epigenetic inheritance, and bet-hedging in bacteria.
Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom. j.w.veening@ncl.ac.uk
Jan-Willem
JW
Veening
Wiep Klaas
WK
Smits
Oscar P
OP
Kuipers
D001412:Bacillus subtilis / Q000235:genetics / Q000502:physiology; D001419:Bacteria / Q000235:genetics*; D018441:Biofilms / Q000254:growth & development; D001709:Biotechnology; D044127:Epigenesis, Genetic; D004926:Escherichia coli / Q000235:genetics / Q000502:physiology; D053263:Gene Regulatory Networks; D042822:Genomic Instability; D007763:Lac Operon; D008957:Models, Genetic; D010641:Phenotype; D013171:Spores, Bacterial / Q000235:genetics; D014170:Transformation, Genetic