IDENTIFICATION OF A BACTERIUM THANKS TO THE GRAM STAINㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤㅤ

By Leïla

The following article was written by Leïla, a Year 12 student who has chosen biotechnology as her field of study. This article is part of the work students do during the techclass in English on Monday afternoons

1. The goal of the experiment

The Gram stain allows to colour bacteria in order to identify two different types of bacteria: Gram+ or Gram-.

2. The description of the experiment

• –  First, we put the bacteria on a slide.
• – Secondly, we add the different dyes such as crystal violet, iodine and fuchsine.
• –  Thirdly, we look at the slide under the microscope:
  • • If bacteria are pink, they are Gram -.
  • • If bacteria are purple, they are Gram +.