Gram staining was developed in the 1800s as a quick and simple procedure to distinguish between Gram positive and Gram negative bacteria. It is one of the first laboratory techniques taught to ...

Gram-negative bacteria's thick outer membrane prevents entry of toxic molecules, including antibiotics. Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to ...

There are many ways of classifying bacteria. One method is based on the cell membrane. In 1884, a bacteriologist named Christian Gram created a test that could determine if a bacterium had a thick, ...

Gram-positive bacteria have thick cell walls. A Gram stain test, which involves a chemical dye, stains the bacterium’s cell wall purple. On the other hand, gram-negative bacteria stain pink instead.