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Flashcards in GRAM -VE Deck (46)
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1

Name 3 gram negative cocci

1. Neisseria
2. Moraxella
3. Veillonella

2

What type of bacteria is Neisseria?

Gram-negative cocci that is facultative aerobic

3

Appearance of Neisseria on gram stain?

Pink;
Cocci - found in pairs, tetrads, short chains & clusters

4

List 2 species of Neisseria that are pathogens

1. Neisseria gonorrhoeae
2. Neisseria meningitidis

5

List 2 species of Neisseria that can be found in the oral cavity

1. Neisseria subflava
2. Neisseria sicca

6

Are the Neisseria species early or late colonizers of tooth?

Early

7

Name a similarity and a difference between Neisseria subflava and Neisseria sicca

S: N. subflava and N. sicca are saccharolytics and polysaccharide producing bacteria found in the mouth
D: N. subflava produces a yellow-green pigment but N. sicca does not produce pigment.

8

State a difference between Neisseria and Moraxella

Neisseria is saccharolytic (i.e. produces polysaccharide) but Moraxella is asaccharolytic (i.e. does not produce polysaccharide)

9

Name a species of Moraxella

Moraxella catarrhalis

10

What do most strains of Moraxella produce? Why is that a danger?

Most strains produce B-lactamase --> complicates antibiotic therapy

11

Where can Moraxella catarrhalis be found?

Commensal of the mouth and upper respiratory tract

12

What is Moraxella catarrhalis a significant pathogen of?

Meningitis, endocarditis, otitis media, maxillary sinusitis

13

Similarity between Moraxella and Veillonella

Both are asaccharolytics (both do not ferment carbohydrates)

14

Where can Veillonella be found?

Mouth and dental plaque

15

Function of Veillonella

Catabolises lactic acid to weaker organic acids (acetate and propionate); hence raising pH of the oral cavity

16

Name the most common species of Veillonella

Veillonella parvula

17

Where can veillonella parvula be found?

Oral cavity and intestines

18

Name 3 species of Veillonella

1. Veillonella Parvula
2. Veillonella Dispar
3. Veillonella Atypica

19

Define GNAB

GNAB = Gram negative anaerobic bacteria - They are a large proportion of oral bacteria found especially in the gingival sulcus and periodontal pocket that is difficult and fastidious to study.

20

Name 3 motile GNAB

1. Selenomonas
2. Centipeda
3. Helicobacteria

21

Name 6 non-motile GNAB

1. Bacteriodes
2. Porphyromonas
3. Prevotella
4. Tannerella
5. Fusobacterium
6. Leptotrichia

22

What are selenomonas associated with?

Periodontitis / Periodontal disease

23

Describe the appearance of Selenomonas

Cresent (moon-shaped) with many flagellae

24

Name 3 species of Selenomonas

1. Selenomonas Sputigena
2. Selenomonas Flueggei
3. Selenomonas Noxia

25

Name a species of Centipeda

Centipeda Periodontii

26

Describe the appearance of Centipeda

flagellae arising from all around the cell

27

Name a species of Helicobacter

Helicobacter pylori

28

What does helicobacter pylori cause?

gastritis, gastric cancer, peptic ulcers

29

Describe the appearance of bacteroides on a CBA

Produces a dark pigment

30

Name a species of bacteroides. Where can it be found?

Bacteroides fragilis; found in mouth and GI tract (esp in the colon)