Question

A bacterial cell that transits from a reservoir or from one host to another, is likely to encounter a range of non-optimal conditions in its new environment. For example, it may be exposed to damaging or toxic physical and chemical conditions. It will need to adapt if it is to survive. Outline what these physical and chemical properties are and give examples of how bacteria adapt to survive in these conditions.

Answer 1

Some of the bacterial adaptations to survive the unfavorable conditions of the host are:

1. Rigid cell wall: The cell wall provides protection against the unfavorable conditions. For example, the capsule layer provides excess protection and interferes with phagocytosis.

2. Rotating flagellae: helps in the motility of the bacterial cell.

3. Pili or fimbriae: hairlike structures (in gram-negative usually) assisting in attachment and transfer of the gentic material to the host.

4. Plasmids: these are extrachromosomal materials that provide resistance to certain drugs.

5. Excretion of toxins: several toxins and enzymes are released that induce various effects on the host boy weakening the immune system and making their job easier.

6. Formation of spores: Spores are a latent stage and are highly resistant to unfavorable conditions. When the conditions are favorable, they transform into dividing stage and reproduce.

For example, a bacteria enters the host and travle using motile structures. It survives phagocytosis and attacks the normal cels of the body to cause infection. The exotoxins and endotoxins released cause infection and wekaening of the immune system.