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High-resolution, long-term characterization of bacterial motility using optical tweezers.

ABSTRACT: We present a single-cell motility assay, which allows the quantification of bacterial swimming in a well-controlled environment, for durations of up to an hour and with a temporal resolution greater than the flagellar rotation rates of approximately 100 Hz. The assay is based on an instrument combining optical tweezers, light and fluorescence microscopy, and a microfluidic chamber. Using this device we characterized the long-term statistics of the run-tumble time series in individual Escherichia coli cells. We also quantified higher-order features of bacterial swimming, such as changes in velocity and reversals of swimming direction.

SUBMITTER: Min TL

PROVIDER: S-EPMC2784139 | biostudies-literature | 2009 Nov

REPOSITORIES: biostudies-literature

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High-resolution, long-term characterization of bacterial motility using optical tweezers.

Min Taejin L TL Mears Patrick J PJ Chubiz Lon M LM Rao Christopher V CV Golding Ido I Chemla Yann R YR

Nature methods 20091004 11

We present a single-cell motility assay, which allows the quantification of bacterial swimming in a well-controlled environment, for durations of up to an hour and with a temporal resolution greater than the flagellar rotation rates of approximately 100 Hz. The assay is based on an instrument combining optical tweezers, light and fluorescence microscopy, and a microfluidic chamber. Using this device we characterized the long-term statistics of the run-tumble time series in individual Escherichia ...[more]

PMID: 19801991

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