MICROANATOMY

Detailed explanation-1: -The Malachite green staining (Schaeffer-Fulton method ) is the most common method used to perform endospore staining. Malachite green stain can also used as a simple stain for bacterial cells. The Schaeffer-Fulton method uses heat to push the primary dye (malachite green) into the endospore.

Detailed explanation-2: -The keratin forming the outer portion of the endospore wall resists dye. The heating of the bacteria will make the spore wall more permeable to the malachite green, and it then attaches to the peptidoglycan.

Detailed explanation-3: -The slide is flooded with malachite green solution and a heat source is used to steam the stain into the cells and the spores. This requires approximately 5 minutes and must be done carefully to achieve steaming and not charring of the sample. This heating step stains the vegetative cells and the endospores.

Detailed explanation-4: -Heat-fix the slide by running it through the flame 3-4 times with the ‘smear’ side up. Do not flame the side with the bacteria! Let the slide cool completely and you are ready to stain it.