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This is a fairly difficult question to answer. Most readings will only tell you that bile salts and crystal violet inhibit gram-positive growth but do not say why. I found some articles that probably would tell us why, but you must pay to subscribe to them. I do know why crystal violet inhibits gram-positive growth though. Crystal violet binds to the peptidoglycan layer of cell membrane in gram-positive bacteria (just like it does in the Gram stain). Gram-negative bacteria have an outer membrane that prevents the crystal violet from attaching to their peptidoglycan layer. Once crystal violet attaches to the peptidoglycan, enzymes called autolysins are unable to cut the polysaccharide linkages between the NAG and NAM residues. The cutting and reforming of the peptidoglycan layer is necessary for cell growth, thus killing the cell. I believe that bile salts work a very similar way just like how penicillin and lysozymes do.
What else can I help you with?
What would be the appearance of the gram positive bacterium if you forget to counterstain with safranin?
If you forget to counter stain color of Gram positive would be violet or blue . The above answer is good. Here is why the above answer is good. Yes it would still be Violet or blue. Gram positive bacteria are gram positive, because it holds onto the crystal violet stain that washes out of gram negative bacteria. Counterstaining with safranian turns gram negative bacteria pink to red only because the crystal violet has washed out of the gram negative. The lighter safranian has little to no effect on gram positive bacteria. The cause of the difference has to do with the makeup of the cell wall in the different bacteria.
Function of Gram's iodine?
Iodine is used as a mordant in the gram staining procedure to make large crystals when it is used with crystal violet dye. In gram positive cell walls those crystals get stuck and wont get washed off with the alcohol. In gram negative cell walls the crystals are washed out.
What happens if not enough alcohol is applied to a gram stain?
Both bacteria types would be stained by the safranin. When the iodine is added, safranin would be "set" in the positive. The decolorizer would wash out the safranin and then application of the crystal violet would stain the negative.
What gram positive cocci bacteria has tetrad?
There are several gram positive cocci bacteria that exist as tetrads. An example is Micrococcus luteus, which can be found on human skin, water, air, etc.Hope this helps.
What happens if crystal violet doesn't stay on cultures long enough?
If crystal violet doesn't remain on cultures long enough during the Gram staining process, the staining may be insufficient, leading to inaccurate results. Bacteria that should be stained purple (Gram-positive) may appear colorless or faintly stained, while Gram-negative bacteria may not take up the counterstain properly, complicating differentiation. This can hinder the identification and classification of bacteria in a sample, affecting further analysis and diagnosis. Proper timing is essential for reliable results in microbiological studies.
What would be the appearance of the gram positive bacterium if you forget to counterstain with safranin?
If you forget to counter stain color of Gram positive would be violet or blue . The above answer is good. Here is why the above answer is good. Yes it would still be Violet or blue. Gram positive bacteria are gram positive, because it holds onto the crystal violet stain that washes out of gram negative bacteria. Counterstaining with safranian turns gram negative bacteria pink to red only because the crystal violet has washed out of the gram negative. The lighter safranian has little to no effect on gram positive bacteria. The cause of the difference has to do with the makeup of the cell wall in the different bacteria.
What is the function of safranin in the Gram staining process?
Crystal violet is used first to stain all bacteria purple. However, when you immerse the bacteria then in alcohol, alcohol affects the permeability of the peptidoglycan layer to crystal violet, blocking its exit from gram-positive cells. This way, gram-positive cells remain purple while gram-negative cells are colourless. Safranin red is then used as a counterstain to make the two types of bacteria more differentiable.
Function of Gram's iodine?
Iodine is used as a mordant in the gram staining procedure to make large crystals when it is used with crystal violet dye. In gram positive cell walls those crystals get stuck and wont get washed off with the alcohol. In gram negative cell walls the crystals are washed out.
What is the stainning method called that can distinguish between two different types of eurobacteria?
I believe what you're looking for is the stain that can differentiate between Gram-negative and Gram-positive bacteria: two types of eubacteria. So the staining method is called the Gram method. Crystal violet will remain trapped in Gram-positive bacteria due to their thicker cell walls, causing them to stain purple. Crystal violet can be washed out of Gram-negative cell walls after alcohol treatment to remove their outer lipid membrane, and the cells can be counterstained with a red, positively charged stain. In the end, Gram-positive bacteria will look purple, and Gram-negative bacteria will look red. See Wikipedia for more details.
What happens if not enough alcohol is applied to a gram stain?
Both bacteria types would be stained by the safranin. When the iodine is added, safranin would be "set" in the positive. The decolorizer would wash out the safranin and then application of the crystal violet would stain the negative.
What gram positive cocci bacteria has tetrad?
There are several gram positive cocci bacteria that exist as tetrads. An example is Micrococcus luteus, which can be found on human skin, water, air, etc.Hope this helps.
What is the function of iodine solution in the gram stain?
It allows the primary stain crystal violet to remain in the cell instead of being washed out. Due to the larger size of the crystal violet molecule, when the ethanol is applied (the decolorizer) the stain will not be washed out of the Gram (+) positive cells.
What happens if you forget to add acetone to a gram negative stain?
When performing the Gram stain, acetone is used as a wash step between the iodine and safranin. By not washing, all stains will remain crystal violet purple, and none will appear safranin red/pink.
Is staphylococcus aureus positive for gelatin hydrolysis?
Bacillus cereus is positive for gelatin hydrolysis. This bacteria is capable of hydrolyzing gelatin(a protein), thus, a nutrient gelatin medium inoculated with this bacteria will remain liquid when placed in an ice bath (don't agitate).the bacteria had proteases that is responsible for the hydrolysis of the gelatin..
When dissolved in water what will not happen to a salt crystal?
The chemical composition remain unchanged.
Bacteria that remain inactive until environmental conditions are favorable?
Endospores.
What produces endospores?
Endospores are produced by certain types of bacteria such as Bacillus and Clostridium when they are exposed to conditions that are unfavorable for growth, such as high temperatures or lack of nutrients. Endospores are a survival mechanism that allows these bacteria to remain dormant until conditions become more favorable for growth.
