Describe in detail what you would see on mixed slide with Gr

Describe in detail what you would see on mixed slide (with Gram negative rods and Gram positive cocci) under the microscope if you did a Gram stain by correctly using the crystal violet, iodine, and safranin, but omitting the alcohol. Why would the slide look like that? (your answer must be 60 words or fewer).

Solution

when both gram positive and gram negative cells are put on same slide and crystal violet staining is done following protocall of gram stain.

All th cells will appear violet under the microscope, if the alcohol addition step is skipped , even if the safraine is added

This is becausethere is a difference in the cell membrane structure of gram positive and gram negative bacteria.

Gram positive bacteria cell wall contains techoic acid layer which is a polymer of n-acetyl glucosamine and N acetyl muramic acid.

Due to this the crystal violet strain is retained

But in case of gram negative bacteria there is a late of lipopolysaccharide

Late=layer

Lipopolysaccharide is dissloved by alchohol and thus gram negative cells take up stain safrainine

So if the alchohol is skipped lipid layer will not be destroyed and crystal violet will be retrained. so safranine will jot be observed in microscope and all cells will appear violet.