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Frequency-dependent Escherichia coli chemotaxis behavior.

ABSTRACT: We study Escherichia coli chemotaxis behavior in environments with spatially and temporally varying attractant sources by developing a unique microfluidic system. Our measurements reveal a frequency-dependent chemotaxis behavior. At low frequency, the E. coli population oscillates in synchrony with the attractant. In contrast, in fast-changing environments, the population response becomes smaller and out of phase with the attractant waveform. These observations are inconsistent with the well-known Keller-Segel chemotaxis equation. A new continuum model is proposed to describe the population level behavior of E. coli chemotaxis based on the underlying pathway dynamics. With the inclusion of a finite adaptation time and an attractant consumption rate, our model successfully explains the microfluidic experiments at different stimulus frequencies.

SUBMITTER: Zhu X

PROVIDER: S-EPMC3412125 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature

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Frequency-dependent Escherichia coli chemotaxis behavior.

Zhu Xuejun X Si Guangwei G Deng Nianpei N Ouyang Qi Q Wu Tailin T He Zhuoran Z Jiang Lili L Luo Chunxiong C Tu Yuhai Y

Physical review letters 20120323 12

We study Escherichia coli chemotaxis behavior in environments with spatially and temporally varying attractant sources by developing a unique microfluidic system. Our measurements reveal a frequency-dependent chemotaxis behavior. At low frequency, the E. coli population oscillates in synchrony with the attractant. In contrast, in fast-changing environments, the population response becomes smaller and out of phase with the attractant waveform. These observations are inconsistent with the well-kno ...[more]

PMID: 22540625

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