The Fast Tumble Signal in Bacterial Chemotaxis

From: Biophysical Journal | Date: June 1, 2004| Author: Jain, Sanjay; Reid, Gordon P; Trentham, David R; Khan, Shahid | Copyright information

ABSTRACT

We have analyzed repellent signal processing in Escherichia coli by flash photorelease of leucine from photolabile precursors. We found that 1), response amplitudes of free-swimming cell populations increased with leucine jump concentration, with an apparent Hill coefficient of 1.3 and a half-maximal dose of 14.4 µM; 2), at a 0-0.5 mM leucine concentration jump sufficient to obtain a saturation motile response, the swimming cell response time of ~0.05 s was several-fold more ...

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