2nd test: Bacillus, Clostridium and GRAM staining Flashcards
GRAM staining
1st step
- Stain the smear with crystal violet for 3-5 minutes
GRAM staining
2nd step
- Pour off the stain, rinsing with tap water
GRAM staining
3rd step
- Stain the smear with Lugols iodine solution
for 1-1,5 minutes
GRAM staining
4th step
- Pour off the stain, rinsing with tap water
GRAM staining
5th step
- Differentiation: drop 5-6 drops of 96% ethanol on the smear, and let it flow down
GRAM staining
6th step
- Immediately rinse with tap water
GRAM staining
7th step
- Counterstaining with fuchsin or safranin
for 0,5-1 minute
GRAM staining
8th step
- Pour off the stain, rinsing with tap water
GRAM staining
9th step
- Drying with filter paper
GRAM staining
In which order do you apply which staining
1. crystal violet for 3-5 minutes
- Lugols iodine solution for 1-1,5 minutes
- drop 5-6 drops of 96% ethanol on the smear, and let it flow down
- Counterstaining with fuchsin or safranin
for 0,5-1 minute
Result of staining with GRAM STAINING of
GRAM + bacteria
Result: GR+ bacteria are blue,
Result of staining with GRAM STAINING of
GRAM - bacteria
GR- bacteria are red or pink,
Result of staining with GRAM STAINING of
Mycobacteria
mycobacteria are colorless,
Result of staining with GRAM STAINING of
Fungi
fungi are like GR+ bacteria.
What is Gram staining on histological slides called?
You can use Gram staining on histological slides as well, in this case the staining is called Brown-Brenn.
The background is yellowish brown, the color of the bacteria is like after a normal Gram staining.
GENUS: BACILLUS
Habitat
Diseased animals (VEGITATIVE)
Environment (SPORE)
GENUS: BACILLUS
MORPHOLOGY
4-5 micro.m ROD, CENTRAL SPORE
CAPSULE
NO FLAGELLA
GENUS: BACILLUS
RESISTANCE
Vegetative bacterium: Several days in carcass
(Skin: 2 weeks, Bonemarrow: 4 Weeks)
56 degrees in 15min
Spore: In soil can survive for more than 50 years
Boiling: 5-10min
Formalin (8-10%): 12-24 hours
GENUS BACILLUS: STAINING
GRAM-POSITIVE
TOLUIDINE-BLUE
(Metachromatic staining)
GENUS BACILLUS: CULTURE
Simple (Nutrient broth or agar, blood agar, air, 37 degrees)
R-S Colonies (depend on CO2)
Capsule: Poly-D-Glutamic acid (= INHIB PHAGOCYT.)
Virulence factor (= INHIB PHAGOCYT.)
Plasmid encoded
Spore: For spore formation
At least 15 degrees
Water
Oxygen
Cations are needed
= DO NOT OPEN CARCASS
37 degrees - finished during 16 hours
18 degrees it will start after 50 hours (2-3 days are needed)
GENUS BACILLUS: BIOCHEMISTRY/ANTIGENS
Active metabolism
Catalase +
Oxidase -
Ag: Capsule (poly-D-glutamic acid) - SAPHROPHYTES, Polysaccharide Hapten - Heat stabile
ASCOLI TEST, B.CEREUS - Cross reaction!
OEDEMA FACTOR
LETHAL FACTOR
PROTECTIVE ANTIGEN
ASCOLI THERMOPRECIPITATION TEST
- Detection of B.Anthracis heat stable cell wall Ag (Crossreacts with B.CERESUS)
GENUS BACILLUS: PATHOGENICITY
Mammals (mainly herbivorous)
GENUS BACILLUS: PATHOGENICITY
Cattle, Sheep
Fatal peracute or acute septicaemic anthrax.
GENUS BACILLUS: PATHOGENICITY
Pigs
Subacute ANTHRAX with oedematous swelling in the pharyngeal region, an intestinal form with higher mortality is less common
GENUS BACILLUS: PATHOGENICITY
Horses
Subacute ANTHRAX with localized oedema, septicemia with collic and enteritis sometimes occur
GENUS BACILLUS: PATHOGENICITY
Humans
Skin, Pulmonary and intestinal form of ANTHRAX
GENUS BACILLUS: PATHOGENICITY
CARNIVORES
Comparatively resistant
GENUS BACILLUS: PATHOGENICITY
BIRDS
Completely resistant