Bacterial cells with thick peptidoglycan and numerous teichoic acid cross-linkages are Gram stained.The organisms stain pink.Which one of the following statements explains this discrepancy?
A)The bacterial cells were most likely not heat-fixed to the slide.
B)The bacterial cells were subjected to the decolorizer too long and were overdecolorized.
C)The lot of Gram-stain reagent is most likely expired.
D)No discrepancy exists;cells with this composition stain pink on Gram stain.

Question

Quizplus · Accepted Answer

Bacteria with thick peptidoglycan and numerous teichoic acid croslinkages are gram-positive organisms.If the bacteria are staining gram-negative,the staining process may have resulted in over decolorization making the cells appear pink.If the smear is a primary smear,reviewing the staining of neighboring cells can be used to assist in the interpretation.If other cells that are typically gram-positive in nature,such as gram-positive cocci in clusters,it is possible that the organisms staining pink are no longer viable preventing the crystal violet from remaining in the deteriorating cell walls of dying cells.

Bacterial Cells with Thick Peptidoglycan and Numerous Teichoic Acid Cross-Linkages