Рет қаралды 4,618
Flagella are locomotry structures help in locomotion
Flagella and pilli are considered as organelles
All flagella have "H" antigens
A flagellum has three components:
1-Filament, which is made up of flagelin protein
2- Hook, which is made up of different proteins
3- Basal body, which contains a rod and rings
In gram+ve bacteria, a flagellum has two rings embedded in cytoplasmic membrane e.g S ring and M ring
But in gram -ve bacteria, a flagellum has 4 rings. L ring is present in outer membrane of cell wall, P ring is present in Peptidoglycans. And S, M rings are present in cytoplasmic membrane
Motors rotate flagella. These motors have 2 imp. components
1- Rotor, which spins
2-Stator, which is stationary and made up of MOT-A, MOT-B proteins
Endoflagella are present in spirochetes
Bacteria move in response to phototaxsis or chemotaxsis
Classification of bacteria on the basis of flagella
1Atrichous bacteria
2-Monotrichous bacteria
3-Amhitrichous bacteria
4-Lophotrichous bacteria
5- Peritrichous bacteria
Pilli and fimbriae are thread like structures help in attachment
Pillus is made up of pillin proteins
Pilli are not considered as locomotry structures, but pilli can help bacteria in twitching and gliding movement
Main role of pilli is to help bacteria in conjugation