Difference between Gram-positive and Gram-negative Bacteria

Gram-positive vs. Gram-negative Bacteria

What is Difference between Gram-positive and Gram-negative Bacteria? Danish scientist Hans Christian Gram designed a method that allowed him to differentiate two types of bacteria based on their cell walls (gram-positive bacteria and gram-negative bacteria). Because of their structural differences, these two types of bacteria do not respond the same way to the antibodies, for that reason, it is important that we know the difference between one and the other; so that we can better understand what utility each type can have or what it might cause.

Difference between Gram-positive and Gram-negative Bacteria

If you have doubts about the difference between gram positive and gram negative, continue reading, because we explain below.

Gram-positive Bacteria

They are those that are characterized to maintain a purple or blue dye once the test of staining or staining of Gram is applied to them. This is due to the structure of your cell wall. The gram-positive does not have outer cell membrane; instead they contain a great amount of peptidoglucano; which is responsible for maintaining the violet coloration.

Many gram-positive bacteria are non-pathogenic, i.e. they do not cause disease; they are also part of the human commensal microbiomes found in the mouth, skin, intestine and respiratory tract. They are also a necessary ingredient in the production of some foods; as is the case of Swiss cheese.

Gram-negative Bacteria

On the other hand, when applied to the aforementioned test, the gram- negative bacteria acquire a red or pink coloration. Unlike gram-positive, they do have an outer cell membrane.

Between 90-95% of gram-negative bacteria are pathogens for humans, in addition, they are generally more resistant to antibiotics or develop resistance to them more quickly than gram positive bacteria. Finally, not all bacteria can be classified by the Gram test.