Fungi are eukaryotic organisms typically having chitin cell walls, but no chlorophyll or plastids. Fungi may be unicellular or multicellular. Eukaryotic pathogens such as fungus are gram-negative when stained with Gram stain. Light microscope is usually used when viewing the results of Gram stain. A gram negative fungus will not retain the dye of the Gram’s stain and it will take on a pinkish color. Subcellular structures of fungi such as endoplasmic reticulum, Golgi apparatus and mitochondrion can also be observed when a fungus is viewed under a light microscope.
