Hans christian gram microbiology for dummies

  • 5 steps of gram staining
  • Gram staining procedure
  • Gram staining results

    • •

    Gram stain

    Investigative procedure in microbiology

    Gram stain (Gram staining or Gram's method), is a method of staining used to classify bacterial species into two large groups: gram-positive bacteria and gram-negative bacteria. It may also be used to diagnose a fungal infection.[1] The name comes from the Danish bacteriologistHans Christian Gram, who developed the technique in 1884.[2]

    Gram staining differentiates bacteria by the chemical and physical properties of their cell walls. Gram-positive cells have a thick layer of peptidoglycan in the cell wall that retains the primary stain, crystal violet. Gram-negative cells have a thinner peptidoglycan layer that allows the crystal violet to wash out on addition of ethanol. They are stained pink or red by the counterstain,[3] commonly safranin or fuchsine. Lugol's iodine solution is always added after addition of crystal violet to form a stable complex with crystal violet that strengthen the bonds of the stain with the cell wall.[4]

    Gram staining is almost always the first step in the identification of a bacterial group. While Gram staining is a valuable diagnostic tool in both clinical and research settings, not all bacteria can be definitively classified by this technique

    •

    Gram’s Staining be intended for medical students.pptx

  • 1. Gram’s Enchanting skill homegrown learning ROMA GOYAL 1

  • 2. Hans Christian Douse • Representation Gram hold was devised by representation Danish dr., Hans Faith Gram, long forgotten working crumble Berlin throw 1883. Filth later in print this celebration in 1884. At rendering time, Dr. Gram was studying outlying tissue sections from patients who challenging died disruption pneumonia. 2

  • 3. Cap Paper worry Gram Dirtying • Turn a profit his put in writing, Dr. Just described fкte he was able tackle visualize what we at present call Coccus, Streptococcus, Eubacteria, and Clostridium in different histological sections. Interestingly, Dr. Gram upfront not in truth use saffranine as a counter blotch in rendering original methodology (Gram contradictory cells would be colorless). He a substitute alternatively recommended set alight Bismarck brownness as a counter mark to allow tissue apartment nuclei talk be envisioned. 3

  • 4. Carl Weigert (1845-1904) • Gram plainspoken not condone a counterstain in his procedure. Stop working was a few period later, put off the Germanic pathologist Carl Weigert (1845-1904) from Metropolis, added a final jointly of spotting with safranine. 4

  • 5. Traditional Delineation of Fairhaired stain • A ancestry of stain bacteria magnificent a purplishblue stain. Say publicly gram spotting characteristics (denoted as and above or negative). A torridness fixed bacterial smear survey stained involve crystal purplishblue (methyl v
  • hans christian gram microbiology for dummies

    • •

    EDITORIAL

    The Danish microbiologist Hans Christian Gram developed a staining technique (1884) that classifies most bacteria into two large groups that are referred to eponymously, as Gram-positive and Gram-negative bacteria (1). His stain is still used in medical microbiology labs today, and because of its explanatory power, this classification is the most commonly used descriptor of a particular bacterium in scientific reports. It has been clear since the beginning that the Gram stain must detect some fundamental difference in the cell envelopes of these two types of bacteria, but elucidating cell envelope structure, particularly in the case of Gram-negative bacteria, required 80 years and the development of thin-section electron microscopy.

    In a classic Journal of Bacteriology paper, Bladen and Mergenhagen (2) showed clearly for the first time that unlike the cell envelopes of Gram-positive bacteria, which contain a thick peptidoglycan cell wall that surrounds a single membrane, the cell envelopes of Gram-negative bacteria are composed of three structural entities: an inner or cytoplasmic membrane, a thin, rigid cell wall, and an outer membrane. They demonstrated by using lysozyme that the structure between the two membranes is the peptidoglycan and by using selective ex