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Bacterial division. Mechanical crack propagation drives millisecond daughter cell separation in Staphylococcus aureus.

ABSTRACT: When Staphylococcus aureus undergoes cytokinesis, it builds a septum, generating two hemispherical daughters whose cell walls are only connected via a narrow peripheral ring. We found that resolution of this ring occurred within milliseconds ("popping"), without detectable changes in cell volume. The likelihood of popping depended on cell-wall stress, and the separating cells split open asymmetrically, leaving the daughters connected by a hinge. An elastostatic model of the wall indicated high circumferential stress in the peripheral ring before popping. Last, we observed small perforations in the peripheral ring that are likely initial points of mechanical failure. Thus, the ultrafast daughter cell separation in S. aureus appears to be driven by accumulation of stress in the peripheral ring and exhibits hallmarks of mechanical crack propagation.

SUBMITTER: Zhou X

PROVIDER: S-EPMC4864021 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Bacterial division. Mechanical crack propagation drives millisecond daughter cell separation in Staphylococcus aureus.

Zhou Xiaoxue X Halladin David K DK Rojas Enrique R ER Koslover Elena F EF Lee Timothy K TK Huang Kerwyn Casey KC Theriot Julie A JA

Science (New York, N.Y.) 20150501 6234

When Staphylococcus aureus undergoes cytokinesis, it builds a septum, generating two hemispherical daughters whose cell walls are only connected via a narrow peripheral ring. We found that resolution of this ring occurred within milliseconds ("popping"), without detectable changes in cell volume. The likelihood of popping depended on cell-wall stress, and the separating cells split open asymmetrically, leaving the daughters connected by a hinge. An elastostatic model of the wall indicated high c ...[more]

PMID: 25931560

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