Exercise 21 - Stepyococci And Enterococci Flashcards Preview

Micro Lab Practical 2 > Exercise 21 - Stepyococci And Enterococci > Flashcards

Flashcards in Exercise 21 - Stepyococci And Enterococci Deck (20)
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0

Gram stain reaction, size, shape, and arrangement of strep

Purple

Cocci

Strepto (chain)

1

What major test differentiates staph vs strep

Catalase test using hydrogen peroxide

Bubbles = staph

No bubbles = strep

2

Know the flow chart for differentiating the different strep bacteria. You do not have to memorize the names of each species at the end of the flow chart

Ok

3

Know which test distinguish the different species of: (flow chart tells you)

Beta hemolytic strep
Alpha hemolytic strep
Gamma hemolytic strep

And hat the + or - results are for all these tests

Yes

4

Biochemical pattern for streptococcus pyrogens and streptococcus pneumoniae

Hi

5

Be able to read all media for + or - reactions

Eek

6

Flow chart for Gram + cocci:

Step 1

Hemolysis on blood agar

7

Flow chart for Gram + cocci:

Beta Hemolytic:

Next step?

Results of this test?

Bacitracin test

+ = Beta Streptococcus Group A

- = Non Group A Streptococcus

8

Flow chart for Gram + cocci:

Alpha Hemolytic:

What's the next step?

What do the results mean?

Optochin test

+ = S = Streptococcus pneumoniae
- = R = Viridans Streptococcus

9

Flow chart for Gram + cocci:

Gamma hemolytic:

What's the next step?

What do the results mean?

Bile Esculin test

+ = continue on with 6.5% salt tolerance test
- = Viridans Streptococcus

10

Flow chart for Gram + cocci:

Gamma hemolytic:

Bile Esculin +:

What's the next step?
What do the results mean?

6.5% salt tolerance test

+ = Enterococcus spp
- = Non-Enterococcus (group D Streptococcus)

11

Blood Agar:

Bacitracin:

What is the purpose of this test

What do the results mean

Differentiate Beta Hemolytic strep species

Zone of inhib = greater than 10mm S - positive for Streptococcus (Group A Beta hemolytic strep)

Zone of inhib = less than 10mm R (others)

12

Blood agar:

Optochin:

What is the purpose

What do the results mean

Differentiate Alpha Hemolytic Strep species

Greater than 14mm S - positive for Streptococcus Pneumoniae

Less than 14 mm R (others)

13

Salt tolerance broth:

What types of test is this?

What are its ingredients

What does it select for

Selective, differential

S - 6.5% NaCL
D - glucose and brom cresol purple

Different strep species

14

Salt tolerance broth:

What is its purpose

What are the + and - results

Differentiate gamma hemolytic strep species

+ = color change to yellow (acid changing BCP from purple to yellow); + Turbidity

- = no color change, no Turbidity (still purple)

15

What is the only hemolytic pathway that requires an extra test if positive at the first test

Gamma hemolytic

16

Bile Esculin Slant:

What type of test is this

Differential

17

Bile Esculin Slant:

What is the purpose of this test

What are the + and - results

Differentiate gamma hemolytic strep species

+ = color change to dark
- = no color change

18

Brain/heart infusion agar slant:

What type of test is this

What does it select for

Enrichment

For fastidious Strep

19

Brain/heart infusion agar slant:

What is its purpose

What are the + / - results

Encourage growth
Catalase test: differentiates Staph vs Strep

+ = bubbles (Staph)
- = no bubbles (Strep)