40.Genus Listeria. Flashcards Preview

Bacto specific oral > 40.Genus Listeria. > Flashcards

Flashcards in 40.Genus Listeria. Deck (10)
Loading flashcards...
1
Q

Habitat?

A

LISTERIA

  1. Habitat: • soil, sewage, • plants, • silage, • gut, • food
2
Q

Morphology?

A
  1. Morphology:

• 1-2 µm thick rods, • flagella • flagella are produced on in room temperature (22 oC)

3
Q

Staining?

A

Staining: • Gram-positive

4
Q

Culture?

A

Culture:

  • simple
  • nutrient agar, nutrient broth,
  • β haemolysis,
  • 4-45 oC
  • pH 5.5-9.6
  • selective:
  • cattle serum – trypaflavin – nalidixic acid • selective enrichment
  • cold enrichment: at 4 oC • U-tube method
5
Q

Biochemistry?

A

Biochemistry:

  • catalase +,
  • oxidase -,
  • fermentative
  • virulence factors
  • listeriolysin O (haemolysin): intra cellular replication • monocytosis factor: cell wall, lipoid
6
Q

Antigens?

A

Antigens:

  • cell wall polysaccharide
  • flagellar protein
  • 13 serotypes (composite):
  • most common ones: 1/2a, 4b
7
Q

Resistance?

A

Resistance:

  • survives in soil for months
  • propagation in soil!
8
Q

Pathogenicity?

A

Pathogenicity:

  • facultative pathogenic
  • virulence:
  • haemolysis
  • lipolysis
  • monocytosis factor
  • cell wall lipoids
9
Q

Pathogenicity of sheep cattle rabbit humans and birds?

A

Pathogenicity: •

sheep: • mainly encephalitis • abortion, septicaemia • cattle: • mainly abortion • encephalitis

  • rabbit: • septicaemia, abortion
  • humans: • abortion, newborn septicaemia, encephalitis
  • birds: • septicaemia
10
Q

Species?

A

Species:

  • L. monocytogenes
  • L. ivanovii • stronger haemolysis, • serotype 5 • facultative intra cellular agents • several saprophytic species

Decks in Bacto specific oral Class (61):