Lab 7- Fusobacterium

Question 1

Morphology

Answer 1

Polymorph, generally no flagella

Question 2

Staining

Answer 2

Gram negative

Irregular

Question 3

Culture

Answer 3

Fastidious !
Protein, yeast extract (blood or serum agar)

Obligate anaerobic
Co2 5-10%

Selective culture:
Crystal violet brilliant green, vankomycin (suppress growth of gram +)

Question 4

Biochem

Answer 4

Inactive
Gelatine, casein

Has proteases (it’s virulence factor)

Question 5

Pathogenicity

Answer 5

Facultative pathogenic

Anaerobic wounds, abscesses, gangrene

Question 6

Can tolerate o2

Answer 6

Absolutely not

Question 7

Spore formation ?

Answer 7

No

Question 8

Species

Answer 8

F. Necrophorum subspecies necrophorum (pathogen)
F. Necrophorum subspecies funduliforme (not so important)

F. Nucleatum

Question 9

F. Necrophorum morphology

Answer 9

Long chains

Question 10

F. Necrophorum culture

Answer 10

Blood agar
Weak hemolysis
Obligate anaerobic

Question 11

F. Necrophorum biochem

Answer 11

Carbs NOT utilized
Lipase
DN-ase
Hyaluronidase

Question 12

F. Necrophorum subspecies necrophorum specifics

Answer 12

Virulence factor Hemolysis
Haemaglutination

Cytotoxins :death of host

Synergism! Helps other bacteria

Calf, piglet, rabbit: necrocillosis
Sheep: foot root (not directly)

Question 13

F. Necrophorum subspecies funduliforme specifics

Answer 13

No heamaglutination
No cytotoxin
No synergism
Not pathogenic

SAPROPHYTE

Question 14

F. Nucleatum specifics

Answer 14

Mainly human, dog, cat

Abscesses, mastitis, metritis, peritonitis, wounds