title: The bacterial cytoplasm has glass-like properties and is fluidized by metabolic activity.
abstract: The physical nature of the bacterial cytoplasm is poorly understood even though it determines cytoplasmic dynamics and hence cellular physiology and behavior. Through single-particle tracking of protein filaments, plasmids, storage granules, and foreign particles of different sizes, we find that the bacterial cytoplasm displays properties that are characteristic of glass-forming liquids and changes from liquid-like to solid-like in a component size-dependent fashion. As a result, the motion of cytoplasmic components becomes disproportionally constrained with increasing size. Remarkably, cellular metabolism fluidizes the cytoplasm, allowing larger components to escape their local environment and explore larger regions of the cytoplasm. Consequently, cytoplasmic fluidity and dynamics dramatically change as cells shift between metabolically active and dormant states in response to fluctuating environments. Our findings provide insight into bacterial dormancy and have broad implications to our understanding of bacterial physiology, as the glassy behavior of the cytoplasm impacts all intracellular processes involving large components.
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT 06520, USA.
authors.forename: Bradley R
authors.initials: BR
authors.lastname: Parry
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT 06520, USA; Howard Hughes Medical Institute, Yale University, New Haven, CT 06520, USA.
authors.forename: Ivan V
authors.initials: IV
authors.lastname: Surovtsev
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT 06520, USA.
authors.forename: Matthew T
authors.initials: MT
authors.lastname: Cabeen
authors.affiliation: Department of Applied Physics, Yale University, New Haven, CT 06520, USA; Department of Physics, Yale University, New Haven, CT 06520, USA; Department of Mechanical Engineering and Materials Science, Yale University, New Haven, CT 06520, USA.
authors.forename: Corey S
authors.initials: CS
authors.lastname: O'Hern
authors.affiliation: Department of Physics, Yale University, New Haven, CT 06520, USA; Department of Mechanical Engineering and Materials Science, Yale University, New Haven, CT 06520, USA; Department of Chemical and Environmental Engineering, Yale University, New Haven, CT 06520, USA; Department of Cell Biology, Yale University, New Haven, CT 06520, USA.
authors.forename: Eric R
authors.initials: ER
authors.lastname: Dufresne
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, CT 06520, USA; Howard Hughes Medical Institute, Yale University, New Haven, CT 06520, USA; Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, CT 06510, USA. Electronic address: christine.jacobs-wagner@yale.edu.
authors.forename: Christine
authors.initials: C
authors.lastname: Jacobs-Wagner
mesh_terms: D055592:Biophysical Phenomena; D016935:Caulobacter crescentus / Q000737:chemistry / Q000166:cytology* / Q000378:metabolism*; D002876:Chromosomes, Bacterial / Q000378:metabolism; D003593:Cytoplasm / Q000737:chemistry; D004926:Escherichia coli / Q000737:chemistry / Q000166:cytology* / Q000378:metabolism; D010957:Plasmids / Q000378:metabolism