Figure 2. Tumbles in wild-type cells involve multiple CW flagella.

(A) A typical time trace from a wild-type cell with 3 flagella. Colors indicate runs/tumbles (white/black, top) and CCW/CW (white/purple, middle). The blue line (bottom) shows the corresponding number of CW flagella at each time point. (B) Same as (A) for a typical CheY* cell with 3 flagella. (C) Mean of the maximum number of CW flagella during a tumble vs number of flagella per cell. Consistently more flagella are CW during tumbles in the wild-type (black circles; N = 61 cells) compared to the CheY* strain (open gray circles; N = 24 cells). Simulations incorporating fluctuations in CheY-P (black line) and without fluctuations (gray dashed lines) reproduce the observed trends (simulations detailed in the text and Figure 4). (D) Cross-correlation between flagella pairs, averaged over all pairs and all cells. Wild-type (black circles) match simulations with fluctuations in CheY-P (black line). CheY* strain (open gray circles) matches simulations without fluctuations in CheY-P (gray dashed line), which exhibit almost no correlation. Error bars denote SEM. See ‘Materials and methods’ for more details.

DOI: http://dx.doi.org/10.7554/eLife.01916.011

Figure 2—figure supplement 1. Flagellar transition rates vs number of flagella per cell.

Flagella motor transition rates, separated into two groups corresponding to cells with a single flagellum (red) and cells with multiple flagella (blue). All data from wild-type cells (N = 52 cells). Error bars denote SEM.

DOI: http://dx.doi.org/10.7554/eLife.01916.012

Figure 2—figure supplement 2. Flagellar transition rates vs number of flagella per cell.

Transitions between the three observed flagella waveforms (normal, semi-coiled and curly-1), separated into two groups corresponding to cells with a single flagellum (red) and cells with multiple flagella (blue). All data from wild-type cells (N = 52 cells). Error bars denote SEM.

DOI: http://dx.doi.org/10.7554/eLife.01916.013