Most species of bacteria can be broadly divided into two groups, known as gram-positive and gram-negative. These categories ...

Gram-positive bacteria are bacteria with thick cell walls. In a Gram stain test, these organisms yield a positive result. Here’s why knowing whether the result is positive or negative is important.

The main benefit of a gram stain is that it helps your doctor learn if you have a bacterial infection, and it determines what type of bacteria are causing it. This can help your doctor determine ...

Gram staining is one way scientists can identify bacteria. Gram-positive bacteria, such as Staphylococcus, appear blue or purple under a microscope when scientists apply a stain. Conversely, Gram ...

Gram negative bacteria. Gram negative bacteria appear a pale reddish color when observed under a light microscope following Gram staining. This is because the structure of their cell wall is unable to ...

In this simplified diagram of gram staining, bacterial cells are first treated with a purple dye called crystal violet. The dye gets into the cells’ peptidoglycan layer (gray), tinting it purple.

Unlike traditional Gram staining, which requires fixing bacteria, this virtual staining approach uses darkfield microscopy that can work with living organisms without the need for any labels.

Compared with other methods, urine Gram stain moderately predicted gram-negative bacteria but added little value to UTI diagnosis in the ED, raising questions about its clinical utility.

Being able to differentiate bacterial species is important for a host of reasons. While molecular techniques can determine the specific species, even without getting into the molecular nitty gritty, ...