What is the purpose of gram staining?
The purpose of gram staining is to decipher what 2 groups a type of bacteria belongs to, gram negative, and gram positive. From this information we can learn more on the bacteria based on the specific characteristics that belong to each individual group.
Gram positive bacteria
Gram positive bacteria appear purple after you have undergone the gram staining process. These type of bacteria have a thin cell wall, packed full with peptidoglycan. The purple colour is caused because of this thick layer of peptidoglycan. The initial stain used during the staining process, crystal violet, is absorbed by this peptidoglycan, being the reason the bacteria retains the purple colour even after being rinsed with ethanol.
The purpose of gram staining is to decipher what 2 groups a type of bacteria belongs to, gram negative, and gram positive. From this information we can learn more on the bacteria based on the specific characteristics that belong to each individual group.
Gram positive bacteria
Gram positive bacteria appear purple after you have undergone the gram staining process. These type of bacteria have a thin cell wall, packed full with peptidoglycan. The purple colour is caused because of this thick layer of peptidoglycan. The initial stain used during the staining process, crystal violet, is absorbed by this peptidoglycan, being the reason the bacteria retains the purple colour even after being rinsed with ethanol.
Gram negative bacteria
Gram negative bacteria have a thick cell wall with a very thin layer of peptidoglycan. It appears pink/red because the initial purple stain, crystal violet, was not soaked up due to the low levels of peptidoglycan. The purple colour was easily washed off by the ethanol. The final stain, safranin is what grants gram negative bacteria their colour.
Gram negative bacteria have a thick cell wall with a very thin layer of peptidoglycan. It appears pink/red because the initial purple stain, crystal violet, was not soaked up due to the low levels of peptidoglycan. The purple colour was easily washed off by the ethanol. The final stain, safranin is what grants gram negative bacteria their colour.