High-resolution, long-term characterization of bacterial motility using optical tweezers.
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.
Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.
Taejin L
TL
Min
Patrick J
PJ
Mears
Lon M
LM
Chubiz
Christopher V
CV
Rao
Ido
I
Golding
Yann R
YR
Chemla
D004926:Escherichia coli / Q000502:physiology*; D005407:Flagella / Q000502:physiology; D008124:Locomotion / Q000502:physiology*; D046210:Microfluidic Analytical Techniques; D008856:Microscopy, Fluorescence / Q000295:instrumentation; D020409:Molecular Motor Proteins / Q000502:physiology; D052898:Optical Tweezers; D012399:Rotation
D020409:Molecular Motor Proteins