Bioécologie et biosystématique des bactéries et virus

Introduction

Bacteria are unicellular organisms, with a single cell forming the bacterium. They can measure from 1 to 10 μm in length.

1- Characteristics 

The classification of bacteria is generally based on the following characteristics:

- cell membrane diameter;

- form.

The cell wall of gram-positive bacteria is consisting of thick layers of peptidoglycan. The cell wall of gram-negative bacteria is consisting of thin layers of peptidoglycan.

During the gram staining procedure, a gram-positive cell retains the purple-colored stain. But do not retain the purple colored stain.

Gram-positive bacteria produce exotoxins.

Gram-negative bacteria produce endotoxins.

3- Bacterial propagation in agriculture