21. Phosphorylation of the basal body acts as a flagellar switch and changes the direction of rotation of the flagellum. 22. Hence the flagellar apparatus is clearly very flexible in evolutionary terms and perfectly able to lose or gain protein components. 23. In a decreasing attractant gradient, there is an increase in bacterial tumbling, produced by a clockwise flagellar rotation. 24. Tektins comprise a family of filament-forming proteins that are coassembled with tubulins to form ciliary and flagellar microtubules. 25. Swarming motility is the coordinated translocation of a bacterial population driven by flagellar rotation in film or on fluid surfaces. 26. Placodeal sensilla are visible only on flagellar segments F7 through F10; pedicel 1.4 times longer than wide. 27. As such, the protein that makes up the flagellar filament, flagellin, is quite similar among all flagellated bacteria. 28. The characteristic sheathed flagellar filaments of " Helicobacter " are composed of two copolymerized flagellins, FlaA and FlaB. 29. This process is responsible for ciliary / flagellar beating, as in the well-known example of the human sperm. 30. They are surprisingly very similar to modern genera, though with a greater number of flagellar segments and longer forewing veins.
