TABLE 2.
Parameters and calculated values for the three bacterial species
| C. crescentus | E. coli | V. alginolyticus | |
|---|---|---|---|
| L, Length of flagellar filament (μm) | 6.0 | 7.3, (29)* | 5.02, (17) |
| 2d, Diameter of flagellar filament (μm) | 0.014, (20) | 0.013, (30) | 0.032, (17) |
| p, Pitch of flagellar helix (μm) | 1.08, (20) | 2.5, (29) | 1.58, (17) |
| r, Radius of flagellar helix (μm) | 0.14, (20) | 0.19, (29) | 0.14, (17) |
| 2a, Cell width (μm) | 0.5 | 1, (29)* | 0.80, (17) |
| 2b, Cell length (μm) | 1.6 | 2, (29)* | 1.92, (17) |
| T0, Stall torque (pN nm) | 350 | 1260, (23) | 4000, (17) |
| ω0, Rotation rate at zero torque (rps) | unknown | 350, (3) | 700, (4) |
| ωknee, Knee rotation rate (rps) | unknown | 170, (3) | 500, (4) |
| ωswim, Motor rate of swimming cells (rps) | 330 | ∼206, (24)† | 650, (4) |
| Tswim, Motor torque of swimming cells (pN nm) | 350 | ∼1000, (3,23,24) | 800, (4) |
| Energy conversion efficiency when swimming | ∼100% | ∼80% | 20% |
| Geometric parameter f (μm/round) | 0.15 | 0.23 | 0.13 |
| ɛ, Swimming efficiency (m/J) | 6.7 × 1010 | 7.3 × 109 | 5.1 × 109 |
The numbers in the parentheses are those of the listed references. The values without reference are obtained in this study. The swimming efficiency is calculated by assuming the cell swims along its long axis, driven by a single polar flagellum for Caulobacter and V. alginolyticus, and by a bundle of four filaments for E. coli.
*
Estimated from the fluorescence image.
†
Assuming the cell body rotates at 7% of the bundle.