Unit 1- Listeria

Question 1

Listeria

Answer 1

Gram positive bacilli, facultative anaerobe, non-spore forming, catalase positive, intracellular, flagella, beta hemolytic, resistant to salt, grows in cold

Question 2

Tumbling Motility

Answer 2

Umbrella shaped colony will grow in a semi solid motility media

Question 3

Virulent Serotypes

Answer 3

1/2a in food, 1/2b, and 4b causes human epidemics

Question 4

Muellen-Hinton Agar

Answer 4

Requires enrichment media, beta hemolytic on blood agar, produces acid fermentation, requires long incubation

Question 5

Enrichment for Growth

Answer 5

FDA and ISO standard enrichment broth media that allow results within 48 hours

Question 6

Resistant Conditions

Answer 6

High salt, inanimate objects, can multiply at fridge temperature

Question 7

Habitat

Answer 7

Soil and decaying vegetation, frank pathogen

Question 8

Most common host

Answer 8

Ruminants, sheep

Question 9

Entry Route

Answer 9

Oral, associated with high iron silage in livestock

Question 10

Exit Routes

Answer 10

Feces, abortion, milk

Question 11

Body Structures

Answer 11

Flagella, internalin, invasion associated protein

Question 12

Intracellular Immune Evasion

Answer 12

Hides from immune patrolling, destroys phagosome to prevent lysozyme binding and allow escape to neighboring cells

Question 13

Enxymes

Answer 13

Superoxide dismutase and phospholipase

Question 14

Superoxide Dismutase

Answer 14

Protects against free radicals from host phagocytes

Question 15

Phospholipase

Answer 15

Pore-forming lysis on endocytosis membrane of the host to free from lysozome

Question 16

Toxins

Answer 16

Beta hemolysin, listeriolysin, bacteriocins, actin polymerizing protein

Question 17

Actin Polymerizing Protein

Answer 17

Directs actin filament formation to propel the bacteria from cell to cell

Question 18

Body Systems

Answer 18

Cell membrane, intestinal barrier, placental barrier, blood-brain barrier

Question 19

Pathogenesis

Answer 19

Attaches to epithelial cells or macrophages, intracellular invasion, intracellular multiplication, and spreads to other cells

Question 20

Intracellular Invasion

Answer 20

Internalin binds surface protein on host and allows entrance to cell

Question 21

Listeriosis

Answer 21

Shedding in feces to infect other hosts, translocation to lymph nodes, spleen and liver infection, bacteremia, placentitis and abortion, meningioencephalitis, and septicemia and shock

Question 22

Neural Form

Answer 22

Microabscess in the brain, ataxia and circling disease, unilateral facial paralysis in silage fed sheep

Question 23

Visceral Form

Answer 23

Septicemia causes gastroenteritis, liver and spleen damage, abortion, myocarditis, osteomyelitis, and mastitis

Question 24

L. monocytogenes

Answer 24

Third leading cause of death from food in the US

Question 25

Diagnosis

Answer 25

FDA or ISO enrichment broth or blood agar

Question 26

Treatment

Answer 26

Beta lactimases

Question 27

Control

Answer 27

Little known besides silage control and vaccine