57. Genera Bacteroides, Dichelobacter and Prevotella.

Question 1

Habitat, Morphology and Staining?

Answer 1

BACTEROIDES, DICHELOBACTER, PREVOTELLA

1. Habitat: • alimentary tract, respiratory way, genitals, mucous membranes, water
2. Morphology: • 3-5 µm rod, fimbria
3. Staining: • Gram negative, • irregular staining

Question 2

Culture, Biochemistry and Pathogenecity?

Answer 2

4. Culture: • fastidious, obligate anaerobic
5. Biochemistry: • more active, proteases, keratinase (D. nodosus) 88
6. Pathogenicity: • facultative pathogens, necrosis, abscesses

Question 3

Species and Pathogenecity?

Answer 3

Species:

• B. fragilis: • mainly human, gut flora, appendicitis, wounds
• Dichelobacter (Bacterioides) nodosus • fimbria • proteolysis, keratinase, • sheep foot rot
• Prevotella (B.) melaninogenica: • dog, cat: putrid inflammations