How do bacteria move without flagella

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The bacterial scourge

It has only been known since 1973 that some bacteria move with the help of rotating flagella. Bacterial flagella, however, have a completely different structure than the flagella of eukaryotic organisms. In most polar flagellated bacteria, the flagellum acts as a thrust flagellum (like a ship's propeller) and pushes the single-cell organism through the medium. The flagella are helically wound threads that are driven by a rotary motor located in the cytoplasmic membrane and rotate around the fictitious axis of the helical line. The movement can be carried out by single flagella or by flagella tufts. The flagella rotate at a relatively high speed; Spiral flagella rotate at around 3000 revolutions / min, i.e. the speed of a medium-sized electric motor. The flagellum rotation causes the bacterium to rotate in the opposite direction like a screwdriver at about a third of this speed and reach speeds of an average of 50 per second.

The flagella of different bacteria differ in terms of their thickness (12-18, length (up to 100 and the amplitude of the helix) from each other. Bacteria can form different flagella types; the arrangement of the flagella is also an important taxonomic feature Flagellar tufts may be inserted at one or both cell poles, or the flagella are distributed over the whole bacterium, as in Escherichia coli (perithric flagellation). The prokaryotic archaea (which are not counted among the bacteria) also have flagella.