What is the Gram stain technique?
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What is the Gram stain technique?
The Gram stain procedure distinguishes between Gram positive and Gram negative groups by coloring these cells red or violet. Gram positive bacteria stain violet due to the presence of a thick layer of peptidoglycan in their cell walls, which retains the crystal violet these cells are stained with.
What are the steps of Gram staining in order?
The Gram staining process includes four basic steps, including:
- Applying a primary stain (crystal violet).
- Adding a mordant (Gram’s iodine).
- Rapid decolorization with ethanol, acetone or a mixture of both.
- Counterstaining with safranin.
What are the steps in Gram staining of bacteria?
The procedure is based on the reaction between peptidoglycan in the cell walls of some bacteria. The Gram stain involves staining bacteria, fixing the color with a mordant, decolorizing the cells, and applying a counterstain. The primary stain (crystal violet) binds to peptidoglycan, coloring cells purple.
What are the techniques of staining?
Preparation
| Sr No. | Name of Indirect Staining Technique |
|---|---|
| 1.) | Gram’s Staining |
| 2.) | Cell Wall Staining a.) Ringer’s method b.)Dyar’s method |
| 3.) | Flagella Staining a.) Leifson’s method b.) Loeffler’s method |
| 4.) | Spirochete Staining a.) Fontana’s method b.) Becker’s method |
What is gram staining in microbiology?
Bacteria that retain the initial crystal violet stain (purple) are said to be “gram-positive,” whereas those that are decolorized and stain red with carbol fuchsin (or safranin) are said to be “gram-negative.” This staining response is based on the chemical and structural makeup of the cell walls of both varieties of …
What is Gram staining in microbiology?
A Gram stain is a test that checks for bacteria at the site of a suspected infection such as the throat, lungs, genitals, or in skin wounds. Gram stains may also be used to check for bacteria in certain body fluids, such as blood or urine.
Why is iodine used in Gram staining?
When iodine is applied, decolorizing time for all cells is longer than without iodine. Thus, iodine penetrates the cell and serves to form a dye-iodine precipitate, and since all cells are less permeable for the dye-iodine toward decolorizing agents, slower removal of it results.
Why is Gram staining 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 an effective treatment plan.
Why is safranin used in gram staining?
The safranin is also used as a counter-stain in Gram’s staining. In Gram’s staining, the safranin directly stains the bacteria that has been decolorized. With safranin staining, gram-negative bacteria can be easily distinguished from gram-positive bacteria.
