Flagella

1. Bacterial Motility
Hugh B. Fackrell

2. 2
11/10/2020
Presentation Outline
l Bacterial Flagella
l Location
l Function
l Structure
l Bacterial vs eukaryotic flagella

3. 3
11/10/2020
Flagellum vs Pilus
Pilus
Flagellum

4. 4
11/10/2020
Pilus (fimbriae)
l An appendage of the bacterial cell used for
transfer of genetic information
l Plural pili

5. 5
11/10/2020
Pili Transfer Plasmids

6. 6
11/10/2020
Bacterial Flagellum
l A thin appendage arising
from one or more
locations on the surface
of the cell wall
l Cellular locomotion
l Moves cell along
gradients e.g. glucose

7. 7
11/10/2020
Types of Motility
l Flagellated
– Flagellum-
l coordinated movement
l tumbling movement
– Axial filament- spirochetes
l Gliding- no visible organelles

8. 8
11/10/2020
Location
l Polar
l Subpolar
l Lateral
l Lophotrichous
l Amphitrichous
l Peritrichous
l Periplasmic

9. 9
11/10/2020
Polar Flagellum

10. 10
11/10/2020
Lophotrichous
Flagella
Spirillum volutns
two or more flagella at the
end of the microbe
Photographs show growth
of flagella during
replication

11. 11
11/10/2020
Amphitrichous
Flagella
l Tufts of flagella at BOTH ends of the
microbe

12. 12
11/10/2020
Peritrichous Flagella

13. 13
11/10/2020
Flagellar tufts

14. 14
11/10/2020
Flagellar tufts

15. 15
11/10/2020
Spirochetes have
Periplasmic Flagella
l Periplasmic flagella are
also called the axial
filament

16. 16
11/10/2020
Axial filaments

17. 17
11/10/2020
Bacterial Flagellum

18. 18
11/10/2020
Rings of Gram Negative
Flagellum
l M: cell
Membrane
l P: Peptidoglycan
l L: Outer Layer
l S: Spacer

19. 19
11/10/2020
Flagellar Structure (details)

20. 20
11/10/2020
Prokaryotic Flagellum

21. 21
11/10/2020
Flagellar Structures

22. 22
11/10/2020
Assembly of Flagellum

23. 23
11/10/2020
Demonstration of Chemotaxis
l Capillary tube
contains attractant
chemical
l Attractants:
– Glucose,Maltose,
Alanine
l Repellents:
– Indole, H+, OH-,
fatty acids

24. 24
11/10/2020
Flagellar Rotation
l Clockwise: Tumbling
l Counterclockwise: coordinated
l Alternate between two rotations

25. 25
11/10/2020
“Run & Tumble” motility

26. 26
11/10/2020
Regulation of Flagellar
Movement

27. 27
11/10/2020
Movement of Flagella
l Whip
l Egg beater