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Asymmetry and aging of mycobacterial cells lead to variable growth and antibiotic susceptibility.

ABSTRACT: Cells use both deterministic and stochastic mechanisms to generate cell-to-cell heterogeneity, which enables the population to better withstand environmental stress. Here we show that, within a clonal population of mycobacteria, there is deterministic heterogeneity in elongation rate that arises because mycobacteria grow in an unusual, unipolar fashion. Division of the asymmetrically growing mother cell gives rise to daughter cells that differ in elongation rate and size. Because the mycobacterial cell division cycle is governed by time, not cell size, rapidly elongating cells do not divide more frequently than slowly elongating cells. The physiologically distinct subpopulations of cells that arise through asymmetric growth and division are differentially susceptible to clinically important classes of antibiotics.

SUBMITTER: Aldridge BB

PROVIDER: S-EPMC3397429 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature

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Asymmetry and aging of mycobacterial cells lead to variable growth and antibiotic susceptibility.

Aldridge Bree B BB Fernandez-Suarez Marta M Heller Danielle D Ambravaneswaran Vijay V Irimia Daniel D Toner Mehmet M Fortune Sarah M SM

Science (New York, N.Y.) 20111215 6064

Cells use both deterministic and stochastic mechanisms to generate cell-to-cell heterogeneity, which enables the population to better withstand environmental stress. Here we show that, within a clonal population of mycobacteria, there is deterministic heterogeneity in elongation rate that arises because mycobacteria grow in an unusual, unipolar fashion. Division of the asymmetrically growing mother cell gives rise to daughter cells that differ in elongation rate and size. Because the mycobacteri ...[more]

PMID: 22174129

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