48. Family Enterobacteriaceae (biochemistry, antigens, resistance, pathogenicity, grouping), genus Edwardsiella.

Question 1

Edwardsiella Habitat culture and pathogenecity?

Answer 1

EDWARDSIELLA
1. Habitat
• intestine (fish, amphibians, birds, mammals), water
2. Culture
• fastidious (vitamins, amino acids needed)
3. Pathogenicity
• E. tarda: eel
• E. ictaluri: septicaemia, ascites (channel catfish)

Question 2

Gram negative anaerobic rods?

Answer 2

GRAM-NEGATIVE ANAEROBIC RODS

Genera

• Fusobacterium
• Bacteroides
• Dichelobacter
• Prevotella

Question 3

Gram negative anaerobic rods habitat, pathogenecity?

Answer 3

GRAM-NEGATIVE ANAEROBIC RODS
1. Habitat:
• mucous membranes
• alimentary tract, respiratory ways, genital tract,
• components of the anaerobic gut flora
2. Pathogenicity:
• facultative pathogens,
• inflammation of the mucous membranes,
• wounds, abscesses
• mainly mixed infections

Question 4

Biochemistry , antigens and Resistance of Enterobacteriaceae?

Answer 4

5. Biochemistry:
   • catalase +,
   • oxidase -,
   • fermentative (acid + gas)
6. Antigens:
   • O: cell wall (LPS)
   • K: capsule (polysaccharide)
   • H: flagella (protein)
   • F: fimbria (protein)
7. Resistance:
   • medium

Question 5

Pathogenecity Enterobacteriaceae?

Answer 5

8. Pathogenicity:
   • saprophytic
   • normal flora (gut, mucous membranes)
   • pathogenic
   • facultative pathogenic
   • obligate pathogenic

Question 6

Grouping Enterobacteriaceae?

Answer 6

9. Grouping:
• genus:
• biochemical characteristics
• species:
• biochemical and serological characteristics
• serogroups:
• O antigens
• serotype:
• O-K-H-F antigens
• biotypes:
• fermentation pattern

Question 7

Lactose positive and lactose negative?

Answer 7

10. Most important genera of the family Enterobacteriaceae:
    • Lactose-positive:
    • Escherichia
    • Klebsiella
    • Enterobacter
    • Lactose-negative:
    • Salmonella
    • Shigella
    • Yersinia
    • Proteus
    • Providencia
    • Edwardsiella
    • Serratia
    • Citrobacter