Prescott's Microbiology 8th Edition by Joanne Willey, Linda Sherwood, Christopher J. Woolverton, Lansing Prescott, John Harley, Donald Klein

Exercise 3

Describe the Gram-staining procedure and explain what happens to a bacterial cell at each step. What step in the procedure could be omitted without losing the ability to distinguish between gram-positive and gram-negative bacteria? Why?

Step 1 of 3

The gram-staining is a procedure that differentiates bacteria by their cell wall. Gram-negative bacteria contain two lipid bilayers with a thin layer of peptidoglycan separating the two membranes. Gram-positive bacteria have only one lipid bilayer with a very thick layer of peptidoglycan.