Is the Gram staining result a good indicator of the phylogen

Is the Gram staining result a good indicator of the phylogenetic relationship between bacteria? Explain.

Solution

Gram staining is a kind of positive staining method which is used to differentiate becteria in to two different groups gram positive and gram negative.The name \"gram staining \"is given after the name of bacteriologist Hanse Christian Gram who discovered this method.

This method is used to classify bacterias in to 2 different classes gram positive and gram negative on the basis of their staining property.

In this method smare of given bacterial sample prepared on glass slide and then stained with primary stain crystal violate and iodine ,then decolonize stain with alcohol and again stained with secondary stain safranin. After this slide is allow to dry and observed under microscope

Gram positive bacterias appear in blue or purple color and gram negative bacterias appear in pink or red colour.

This difference in staining property is due to the amount of peptidoglycan in the cell wall .

larger amount of peptidoglycan present in cell wall of gram positive bacteria which retain the Crystal violet iodine complex and trap the complex in larger and thicker peptidoglycan layer,when It is decolorized with alcohol,traped crystal violate iodine complex remain fixed in cell wall .And hence there is no effect of secondary stain safranin on it because cell wall already has been taken colour of crystal violate.

In gram negative bacterias cell wall contain very less peptidoglycan which is not able to trap Crystal violet iodine complex effectively.and hence it soon decolorized by alcohol.When safranin stain used to stain it,it easily takes it colour and appear pink or red.

On the basis of cell wall structure gram staining method gives different results and indicates though bacterias originate from the same ancestors but due to change in cell wall structure they can be classified as gram positive and gram negative.