1

Section 1: Cell Structure and Function

Motility

A. Flagella

Section 1: Cell Structure and Function

Motility

B. Flagellum Structure

2

Section 1: Cell Structure and Function

Motility

B. Flagellum Structure

Section 1: Cell Structure and Function

Motility

B. Flagellum Structure

The flagellar apparatus consists of several distinct proteins:

3

Section 1: Cell Structure and Function

Motility

B. Flagellum Structure

Section 1: Cell Structure and Function

Motility

C. Chemical Structure

4

Section 1: Cell Structure and Function

Motility

C. Chemical Structure

Section 1: Cell Structure and Function

Motility

C. Chemical Structure

5

Section 1: Cell Structure and Function

Motility

C. Chemical Structure

Section 1: Cell Structure and Function

Motility

C. Chemical Structure

6

Section 1: Cell Structure and Function

Motility

D. Flagellum motility

Section 1: Cell Structure and Function

Motility

D. Flagellum motility

Ex. GN cell

7

Section 1: Cell Structure and Function

Motility

D. Flagellum motility

Section 1: Cell Structure and Function

Motility

D. Flagellum motility

8

Section 1: Cell Structure and Function

Motility

D. Flagellum motility

Section 1: Cell Structure and Function

Motility

D. Flagellum motility

How fast do bacterial cells move?

9

Section 1: Cell Structure and Function

Motility

D. Flagellum motility

Relative Speeds of Organism

Organism Kilometers/hr Body lengths/sec

Section 1: Cell Structure and Function

Motility

E. Gliding motility

10

Section 1: Cell Structure and Function

Motility

E. Gliding motility

Section 1: Cell Structure and Function

Motility

F. Periplasmic flagella - spirochetes

11

Section 1: Cell Structure and Function

Motility

F. Periplasmic flagella - spirochetes

So, why are bacteria motile?

12

Section 1: Cell Structure and Function

Motility

G. Taxis or Directed Motility

Chemotaxis -

Phototaxis -

Aerotaxis -

Magnetotaxis -

Section 1: Cell Structure and Function

Motility

G. Taxis or Directed Motility

Chemotaxis -

Phototaxis -

Aerotaxis -

Magnetotaxis -

Bacillus subtilis on agar withhigh to low (a-d) peptone conc.

13

Section 1: Cell Structure and Function

Motility

G. Taxis or Directed Motility

Chemotaxis -

Phototaxis -

Aerotaxis -

Magnetotaxis -

Section 1: Cell Structure and Function

Motility

G. Taxis or Directed Motility

Chemotaxis -

Phototaxis -

Aerotaxis -

Magnetotaxis -

Low tech backup

14

Section 1: Cell Structure and Function

Motility

G. Taxis or Directed Motility

Chemotaxis -

Phototaxis -

Aerotaxis -

Magnetotaxis -

Section 1: Cell Structure and Function

Motility

G. Taxis or Directed Motility

Chemotaxis -

Phototaxis -

Aerotaxis -

Magnetotaxis -

15

Section 1: Cell Structure and Function

Motility

G. Taxis or Directed Motility

Chemotaxis -

Phototaxis -

Aerotaxis -

Magnetotaxis -

1 µm

Section 1: Cell Structure and Function

Motility

G. Taxis or Directed Motility

Chemotaxis -

Phototaxis -

Aerotaxis -

Magnetotaxis -