Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
6 Cards in this Set
- Front
- Back
- 3rd side (hint)
Bacitracin "A Disk"
|
1) Take a well isolated colony from a Beta hemolytic sheep blood and streak for isolation.
2) Use the loop and stab the primary and secondary streaks to detect Streptolysin O. 3) With flamed forceps, remove a disk and apply it to the junction of the promary and secondary streak and press gently. 4) Incubate at 37 for 24 hours. |
Interpritation
Measure the zone of inhibition. Used to differentiate between Group A Strep. (S. pyogenes) and other Beta hemolytic Strep. |
|
Beta Lactamase
|
1) Use a disc and place it into and empty petri dish or slide.
2) Moisten disk with 1 drop of purified water. 3) With sterile loop, remove several isolated colonies and smear onto the disk and look for a color change. |
Interpritation:
A color change from yellow to red is a POSITIVE. Used for Beta Lactamase positive organisms. Staphylococcus aureus, Haemophilus influenzae, Niesseria gonorrhoeae, B. catarrhalis, Anaerobic bacteria |
|
Bile Solubility
|
1) Test a 24 hour growth on Sheep Blood and place a drop of 2% Sodium desoxycholate over a single colony.
2) incubate for 15 - 30 minutes. 3) Look for the colony to disapear. |
Interpritation:
If the colony has disolved and left some slight hemolysis (bruise) then it is POSITVE. Used for identifiing Streptococcus pneumoniae |
|
Bile Esculin Agar
|
1) Inoculate the bile esculin agar by using a pure culture and streaking the slant.
2) Incubate (cap loose) for 24 hours. 3) Observe for a color change |
Interpriation:
If the color changed from brown to black the test is POSITVE. If no color change make sure there was growth, if growth and no color change then NEGATIVE. |
|
CAMP
|
1) Steak a Sheep Blood down the middle with Staphylococcus aureus.
2) Streak a straight line of the test organism perpendicular to the Staph aureus and stop just before. |
Interpritation:
Observe for an arrow head zone of hemolyisis. Used to identify Group B (Streptococcus agalactiae) from other Streptococcus spp. |
|
Catalase
|
1) Place a colony on a slide and then place a drop of h2o2 on top.
2) Observe for bubbles |
Interpratation:
If lots of bubbles form it is a POSITIVE. Used for differentiation of Strep (-) - Staph (+) - Micro (+), Bacillus (+) - Clostridium (-), Listeria (+) - Erysipelothrix (-) |