Page 33 - MNU microbiology theoritical 2025

General Microbiology & Immunology (PM 401) Second level Semester 4 2024/2025

Function of teichoic acid:

- It contributes to the overall rigidity of the cell wall, which is important for the

maintenance of the cell shape, particularly in rod-shaped organisms.

- It plays a role in resistance to adverse conditions like high temperatures and high

salt concentrations, as well as to β-lactam antibiotics.

3- Surface proteins

- The outer surface of the peptidoglycan is

studded with surface proteins that differ with

the strain and species of the bacterium.

- The surface proteins carry out a variety of

activities, including :

⮚ Functioning as enzymes .

⮚ Serving as adhesins: Adhesins (enable the

bacterium to adhere to host calls and other

surfaces).

⮚ Occasionally functioning as invasins (enable some bacteria to penetrate host cells.

4- Periplasm
- The periplasm is the gelatinous material between the peptidoglycan and the

cytoplasmic membrane

- The periplasm contains enzymes for nutrient breakdown.

General Microbiology & Immunology (PM 401) theoretical handbook Page 22