Engines of the nanoworld: bacterial flagella

Bacterial flagella: rotating helical propellors composed of a single
protein producing thrust allowing swimming through fluids.
• Flagella of E. coli can rotate at up to 18,000 rpm (300 revolutions per sec); the
fastest recorded are flagella of Vibrio alginolyticus -clocked at rotation rate
of 102,000 rpm!! (1,700 rps - see Nature 371, 1994, 752).
• Bacteria can swim at a rate of 100 micrometres per sec or more (100 cell
lengths per sec) note: 1 micrometre = a thousandth of a millimetre
• If cars could be propelled at equivalent speeds to
bacterial speeds relative to their dimensions (car
length), they would break the sound barrier!