Flagellar motility

Broadhead R, Dawe HR, Farr H et al. Flagellar motility is required for the viability of the bloodstream trypanosome. Nature 2006 440(7081) 224-7. 

There are various types of flagellar motility, which depend on the number and location of the flagella in the cell and on the species (Table 1). In some species (e.g., Pseudomonas species, Spirillum species, Chromatium species and Halobacteria), the cells swim forward and backward, and... 

Table 4. Examples of responses to chemotactic stimuli in bacteria with flagellar motility. ...

Mortimer, S.T., Schoevaert, D., Swan, M.A. and Mortimer, D. (1997). Quantitative observations of flagellar motility of capacitating human spermatozoa. Hum. Reprod. 12, 1006-1012. 

But in the lab, it took less than four days. .. T. B. Taylor et aL Evolutionary resurrection of flagellar motility via rewiring of the nitrogen regulation system. 2015. Science 347(6225), p. 1014. DOI 10.1126/science.l259145. 

Blue-green and red algae are sharply set off from the green and brown algae by possession of accessory chemosynthetic chromoproteins which contain bile pigment-like compounds, and by the absence of flagellar motility. 

Huang, B. (1986). Chlamydomonas reinhardtii. A model system for genetic analysis of flagellar structure and motility. Inti. Rev. Cytol. 99, 181-215. 

When microtubules were visualized by electron microscopy (EM), after the improvement of methods of fixation, it was realized that they formed the structural basis of flagellar axonemes and of so-called spindle fibers, as well as occurring as individual filaments in the cytoplasm. Their designation as part of the cytoskeleton suggested that they acted mainly as fixed structural supports. Subsequent research has focused more and more on their dynamic behavior and on their role as tracks for motor proteins, which may, for example, transport chromosomes during cell division. Microtubules are found in all eukaryotic cells and are essential for many cellular functions, such as motility, morphogenesis, intracellular transport, and cell division. It is that dynamic behavior that allows microtubules to fulfill all of these functions in specific places and at appropriate times in the cell cycle. 

Attachment of bacteria. At low ionic strength of the medium — as in many freshwaters — bacteria-surface interactions are controlled by the effects of van der Waals attraction and electrostatic repulsion. At high ionic strength — as in seawater — steric interactions between the outer cell surface macromolecules and the substratum gain in importance (van Loosdrecht et al., 1989 Rijnaarts etal., 1999). Additionally, flagellar and twitching motility of bacteria was found to be essential in the process of attachment by bacteria onto surfaces (Pratt and Kolter, 1998 O Toole and Kolter, 1998). It seems that extracellular polysaccharides of bacteria are not involved in the adhesion process itself. However, bacterial extracellular polysaccharides are necessary for the development of a biofilm and for the formation of microcolonies (Allison and Sutherland, 1987 Hoyle et al., 1993). 

O Toole, G. A., and R. Kolter. 1998. Flagellar and twitching motility are necessary for Pseudomonas aeruginosa biofilm development. Molecular Microbiology 30 295-304. 

It is thus clear that the nature of the driving force which powers the flagellar motor of halobacteria, remains a problem to be solved. To discriminate between H - and Na" -motors, one should study motility in a Na -free medium. If it is the Na motor that is inherent in halobacteria, they must be motionless without added Na, and a pulse of Na must activate the motility even in the presence of a protonophore. 

Campylobacter i2iS polar flagella, which are essential for motility. It has been shown that the motility imparted by the flagella is required for colonization of the gastrointestinal tract and invasion of intestinal epithelial cells in vitro The Campylobacter flagellar filament is composed of two flagellin structural proteins FlaA... 

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