What are Corynebacterium metachromatic granules made of?
polymerized inorganic phosphate
Volutin granules, sometimes termed metachromatic granules because of their colour reaction with the dyes used in light microscopy, contain polymerized inorganic phosphate, an energy-rich compound that acts as a reserve store of energy and of phosphate.
What are metachromatic granules in Corynebacterium diphtheriae?
Special stains like Albert’s stain and Ponder’s stain are used to demonstrate the metachromatic granules formed in the polar regions. The granules are called polar granules, Babes Ernst granules, volutin granules etc. An enrichment medium, such as Löffler’s medium, is used to preferentially grow C. diphtheriae.
What is the granule present in Corynebacterium diphtheriae?
Volutin granules are characteristically present in diphtheria bacilli.
What is in the granules of Corynebacterium?
Volutin granules are intracellular storages of complexed inorganic polyphosphate (poly P). Histochemical staining procedures differentiate between pathogenic corynebacteria such as Corynebacterum diphtheriae (containing volutin) and non-pathogenic species, such as C. glutamicum.
Where the metachromatic granules are present?
prokaryotic cell
Metachromatic granules are the cell inclusions mostly found in the prokaryotic cell. It appears red, when stained with blue dyes in certain bacteria, yeasts, yeast like fungi, and protozoa.
Why is it called metachromatic granules?
Due to the ability of inorganic granules in bacteria to pick up different colours with basic dyes, they are referred to as metachromatic granules.
Why the granules are called metachromatic?
These granules are described metachromatic because they can take a color different from that of the dye. For example, metachromatic granules will stain pink with methylene blue. Synonym(s):
What are metachromatic granules?
Metachromatic granules are the cell inclusions mostly found in the prokaryotic cell. It appears red, when stained with blue dyes in certain bacteria, yeasts, yeast like fungi, and protozoa.
Why it is called metachromatic granules?
What is the meaning of metachromatic?
Definition of metachromatic 1 : staining or characterized by staining in a different color or shade from what is typical metachromatic granules in a bacterium. 2 : having the capacity to stain different elements of a cell or tissue in different colors or shades metachromatic stains.
What is metachromatic property?
Metachromasia describes the phenomenon in which certain tissue constituents reacting with a single dye show different colors from that of the dye solution.
What is a metachromatic granule?
Volutin, or metachromatic granules, contains polymerized phosphate and represents a storage form for inorganic phosphate and energy. Many bacteria possess lipid droplets that contain polymeric esters of poly-β-hydroxybutyric acid or related compounds.
What is metachromatic tissue?
Metachromasia (var. metachromasy) is a characteristical change in the color of staining carried out in biological tissues, exhibited by certain dyes when they bind to particular substances present in these tissues, called chromotropes.
What are metachromatic cells?
What stain can be used to reveal the metachromatic granules?
Methylene blue is used to determine the morphology of fusiform and spirochetes in oral infections. It is also the stain of choice for identifying the metachromatic granules in Corynebacterium diphtheriae. The granules will stain a distinctly deeper blue than the surrounding blue bacteria.
Which cell shows metachromasia feature?
Metachromatic staining is important in the detection of mast cells and is strongly recommended as a routine stain for this purpose. One of the most frequently metachromatic stains is toluidine blue which stains the mast cell granules purple-to-red (Fig. 1).
What is metachromasia in histology?
Metachromasia may be defined as the staining of tissue or tissue components such that the color of the tissue-bound dye complex differs significantly from the color of the original dye complex to give a marked contrast in color (Pearse 1960).
Which stain used in Corynebacterium?
Albert’s staining technique
Albert’s staining technique is a type of special staining technique since it is used to demonstrate a special structure in bacteria. It is chiefly used to demonstrate metachromatic granules found in Corynebacterium diphtheriae. This bacterium is responsible for the disease diphtheria.
What is meant by metachromasia?
Medical Definition of metachromasia 1 : the property of various tissues of staining in a different color (as when treatment with a blue aniline dye makes a cellular element red) 2 : the property of various biological stains that permits a single dye to stain different tissue elements in different colors.
What is metachromatic granules staining?
Albert’s Metachromatic Stain demonstrates the presence of metachromatic granules found in Corynebacterium diphtheria. The granules stain purple-black against the light green counterstained cytoplasm. This helps to distinguish diphtheria from most of the short nonpathogenic diphtheroides which lack granules.
How are metachromatic granules characterized in Clostridium diphtheriae?
Typical metachromatic granules are seen in methylene blue stain or in Albert stain. C. diphtheriae appears as green bacilli with bluish-black metachromatic granules in Albert stain.
What are the characteristics of Corynebacterium diptheriae?
Appearance of many tapered, irregularly stained, pleomorphic (typically arranged in Chinese letter or cuneiform arrangements) gram-positive rods is suggestive of Corynebacterium diptheriae. Typical metachromatic granules are seen in methylene blue stain or in Albert stain.
What is the difference between internal metachromatic granules and the Bacillus?
Internal metachromatic granules densely stain ruby red while the rest of the bacillus stains blue, when stained with an aniline dye such as toluidine blue O or methylene blue
What are the granules of Corynebacterium?
The granules are called polar granules, Babes Ernst granules, volutin granules etc. An enrichment medium, such as Löffler’s medium, is used to preferentially grow C. diphtheriae. After that, a differential plate known as tellurite agar, allows all Corynebacteria (including C. diphtheriae) to reduce tellurite to metallic tellurium.