Dictionary > Gram-indeterminate bacteria

Gram-indeterminate bacteria

Definition
noun, singular: gram-indeterminate bacterium
Bacteria that do not respond to gram staining and, therefore, are indeterminate as either Gram-positive or Gram-negative
Supplement
Gram’s method or gram staining is a simple microbiological procedure that enables quick identification of bacterial species as either gram-positive or gram-negative. Bacterial cells that are violet in color from the primary staining (with crystal violet dye) under the microscope are called gram-positive. Bacterial cells that lose the violet color and take the counterstain color are called gram-negative bacteria. The differing color results in bacterial cells after gram staining are associated with the structural differences in bacterial cell’s outer covering. Gram-positive bacteria have a thick cell wall comprised of a lot of peptidoglycans and teichoic acids that enable them to retain the crystal violet colour. Gram-negative bacteria have less peptidoglycan. The crystal violet gram stain colour is easily lost from ethanol-alcohol mix during decolorization. Because of this, they can be stained with the safranin dye (pink) after counterstaining. There are certain bacteria that are not responding the same way to gram staining, such as acid fast bacteria. It is because they have a different type of cell envelope. The fatty acids in their cell wall resist gram staining. For this type of bacteria, Ziehl-Neelson staining method is used.
Compare:

See also:

  • gram staining


  • You will also like...

    Transpiration
    Water in Plants

    The movement of molecules (specifically, water and solutes) is vital to the understanding of plant processes. This tuto..

    "Cronopio dentiacutus", a prehistoric mammal (an illustration)
    Mammalian Ancestors

    Mammals are a diverse group of organisms, where most of them develop their offspring within the uterus of the mother. Ov..

    Darwin's Finches - Natural Selection
    Darwin and Natural Selection

    This tutorial investigates the genetic diversity in more detail. It also delineates how certain alleles are favored over..

    Stem
    Stems

    Stems primarily provide plants structural support. This tutorial includes lectures on the external form of a woody twig ..

    Angle Oak Tree
    Seed Plants

    Seed plants are vascular plants. They differ from the other vascular plants in producing seeds that germinate into a new..

    Early Mammals on Earth
    Early Mammals on Earth

    The Earth's ecosphere was rapidly changing and throwing up a wide range of ecological niches that new adaptive organisms..

    Related Articles...

    No related articles found

    See all Related Topics